Recent Research Suggests That Negative Memories May Be Erased By? The 135 Top Answers

Minutes before her biology test, Katie tries to learn the definition of “osmosis” from her class notes. She repeats the definition over and over in her mind until she’s sure she’ll remember it. Which of the following methods does Katie use to memorize the definition?

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What is amnesia? Amnesia is a form of memory loss. Some people with amnesia have trouble forming new memories. Others cannot remember facts or past experiences. People with amnesia usually retain the knowledge of their own identity in addition to their motor skills. Mild memory loss is a normal part of aging. Significant memory loss or the inability to form new memories may indicate the presence of an amnestic disorder.

Symptoms of Amnesia The primary symptom of amnesia is memory loss, or the inability to form new memories. If you have amnesia you may experience: Difficulty remembering facts, events, places, or specific details (which can range from what you ate this morning to the name of the current president)

an impaired ability to learn new information

confusion

an inability to recognize places or faces

Confabulation, where your brain subconsciously invents false memories to fill in memory gaps. Your motor skills, such as your ability to walk, and your language skills are retained.

Types of Amnesia There are several types of amnesia, including the following: Retrograde Amnesia If you suffer from retrograde amnesia, you lose existing memories that you have previously made. This type of amnesia usually affects newly formed memories first. Older memories such as B. Memories from childhood are usually affected more slowly. Conditions such as dementia cause gradual retrograde amnesia. Anterograde Amnesia If you have anterograde amnesia, you cannot form new memories. This effect can be temporary. For example, you can experience it during a power outage caused by drinking too much alcohol. It can also be permanent. You can experience it when the area of ​​your brain known as the hippocampus is damaged. Your hippocampus plays an important role in forming memories. Transient Global Amnesia (TGA) Transient Global Amnesia (TGA) is a poorly understood condition. As you develop it, you will experience confusion or excitement that comes and goes over the course of several hours. Memory loss can occur in the hours leading up to the attack, and you likely won’t have a lasting memory of the experience. Scientists believe TGA is the result of seizure-like activity, or a brief blockage in the blood vessels that supply your brain. It is more common in middle-aged and older adults. Infantile or childhood amnesia Most people cannot remember the first 3 to 5 years of life. This common phenomenon is called infantile or childhood amnesia. Dissociative Amnesia If you suffer from dissociative amnesia, you have trouble remembering important information about yourself, such as: B. Your name, your personal history or family and friends. Dissociative amnesia can be caused by a traumatic or stressful event, such as B. being in combat or becoming a victim of a crime. It usually comes on suddenly and can last minutes, hours, or days. In rare cases it can take months or years. Post-Traumatic Amnesia (PTA) Most people who are hospitalized for a traumatic brain injury have post-traumatic amnesia (PTA), according to research. PTA can occur after a period of unconsciousness. You are awake, but you can behave and speak in bizarre ways that are not like yourself. You may not be able to remember events that happened minutes or hours ago. The duration of the PTA can indicate the severity of the brain injury. According to Headway, a charity for brain injury survivors, PTA can take less than 1 hour for mild trauma or more than 24 hours for severe brain injury. Drug-induced amnesia This type of memory loss can occur when you take certain drugs. The following drugs can cause amnesia: Benzodiazepines such as alprazolam (Xanax) and chlordiazepoxide (Librium)

Sedatives such as zolpidem (Ambien) and zopiclone (Imovane)

General anesthetic drugs such as pentobarbital sodium (Nembutal sodium) and phenobarbital

Rape drugs such as flunitrazepam (Rohypnol) and ketamine Drug-induced amnesia is usually temporary. It’s especially evident in older adults who may be taking various medications.

Complications of Amnesia People who have even mild amnesia may experience a reduced quality of life. It can be difficult to carry out daily work and social activities as it is difficult to recall previous memories and create new ones. In some cases, lost memories cannot be recovered. People with severe amnesia may need 24-hour monitoring.

Treating amnesia To treat amnesia, your doctor will focus on the underlying cause of your condition. Chemically induced amnesia, such as from alcohol, can be corrected with detoxification. Once the drug is removed from your system, your memory problems will likely subside. Amnesia from mild head trauma can resolve in minutes or hours without treatment. Amnesia from a severe head injury can last up to 1 week. In rare cases, amnesia can last for months due to a very serious head injury. Amnesia from dementia is often incurable. However, your doctor may prescribe medications to support learning and memory, such as: such as donepezil (Aricept), galantamine (Razadyne ER), or rivastigmine (Exelon). If you have persistent memory loss, your doctor may recommend occupational therapy. This type of therapy can help you learn new information and memory skills for everyday life. Your therapist can also teach you how to use mnemonics and techniques for organizing information to make it easier to recall.

Preventing Amnesia These healthy habits can reduce your risk of blackouts, head injuries, dementia, stroke, and other potential causes of memory loss: Avoid heavy alcohol or drug use.

Use protective headgear when playing sports that put you at high risk of concussion.

Wear a seat belt when traveling by vehicle.

Treat infections promptly so they don’t spread to your brain.

If you are elderly, have your eyes checked annually and ask your doctor or pharmacist about any prescribed medications that may cause dizziness. This can help prevent falls.

Stay mentally active throughout your life. For example, take classes, explore new places, read new books, and play mentally challenging games.

Stay physically active throughout your life.

Eat a heart-healthy diet, including fruits, vegetables, whole grains, and low-fat proteins. This helps prevent strokes and other cardiovascular problems that can cause amnesia, and also provides nutrients to boost your brain health.

drink enough Research shows that even mild dehydration can impair brain function, especially in women.

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9.1 Memories as Types and Stages

Learning Outcomes Compare and contrast explicit and implicit memory and identify the features that define both. Explain the function and duration of eidetic and echoic memories. Summarize the capacities of short-term memory and explain how working memory is used to process information it contains.

As you can see in Table 9.1, “Memory Conceptualized in terms of types, stages, and processes,” psychologists conceptualize memory in terms of types, stages, and processes. In this section we consider the two types of memory, explicit memory and implicit memory, and then the three main memory stages: sensory, short-term, and long-term (Atkinson & Shiffrin, 1968). Then, in the next section, we will look at the nature of long-term memory, with a particular focus on the cognitive techniques we can use to improve our memory. Our discussion will focus on the three processes central to long-term memory: encoding, storage, and retrieval.

Table 9.1 Storage conceptualized in terms of types, stages, and processes. As types of explicit memory

Implicit memory as stages of sensory memory

short-term memory

Long-term memory as encoding processes

storage

retrieval

Explicit Reminder

When we assess memory by asking a person to consciously recall things, we measure explicit memory. Explicit memory refers to knowledge or experiences that can be consciously recalled. As you can see in Figure 9.2, “Types of Recall”, there are two types of explicit recall: episodic and semantic. Episodic memory refers to the first-hand experiences we have (e.g., memories of our high school graduation day or that amazing dinner we had in New York last year). Semantic memory refers to our knowledge of facts and concepts about the world (e.g. that the absolute value of −90 is greater than the absolute value of 9 and that a definition of the word affect means “the experience of feelings or Emotions” is. ).

Explicit memory is assessed using measures that require the person being tested to consciously try to recall the information. A recall test is a measure of explicit memory in which previously remembered information is retrieved from memory. We rely on our recall memory when taking an essay test because the test requires us to generate previously remembered information. A multiple-choice test is an example of a recognition memory test, a measure of explicit memory that determines whether information has been seen or learned before.

Your own experience with testing will probably lead you to agree with the scientific research that remembering is harder than recognizing. The callback required for essay tests involves two steps: first generating an answer and then determining whether it appears to be the right one. As with a multiple-choice test, recognition involves only determining which item from a list appears most correct (Haist, Shimamura, & Squire, 1992). Although they involve different processes, recall and recognition memory measures tend to be correlated. On the whole, students who do better on a multiple-choice test will also do better on an essay test (Bridgeman & Morgan, 1996).

A third way to measure memory is known as relearning (Nelson, 1985). Relearning (or savings) measures assess how much faster information is processed or learned when re-studied after it has already been learned but then forgotten. For example, if you have taken some French courses in the past, you may have forgotten most of the vocabulary you learned. But if you worked on your French again, you would learn the vocabulary much faster the second time. Relearning can be a more sensitive measure of memory than recall or recognition because it allows memory to be scored in terms of “how much” or “how fast” rather than simply “right” versus “wrong” answers. Relearning also allows us to measure memory for actions such as driving a car or playing a piano piece, as well as memory for facts and figures.

Implicit Memory

While explicit memory consists of things that we can consciously report, implicit memory refers to knowledge that we cannot consciously access. However, implicit memory is extremely important to us because it directly affects our behavior. Implicit memory refers to the influence of experiences on behavior, even when the individual is unaware of those influences. As you can see in Figure 9.2, “Memory Types,” there are three general types of implicit memory: procedural memory, classical conditioning effects, and priming.

Procedural memory refers to our often inexplicable knowledge of how to do things. When we go from one place to another, talk to another person in English, dial a cell phone, or play a video game, we use procedural memory. Procedural memory allows us to perform complex tasks even though we may not be able to explain to others how to perform them. There’s no way to tell someone how to ride a bike; a person must learn by doing. The idea of ​​implicit memory helps explain how infants are able to learn. The ability to crawl, walk, and speak are processes, and these skills are developed easily and efficiently while we are children, although as adults we have no conscious memory of having learned them.

A second type of implicit memory is classic conditioning effects, in which we learn, often without effort or awareness, to associate neutral stimuli (like a sound or a light) with another stimulus (like food), eliciting a naturally occurring response, like Pleasure or salivation. Memory for the association is demonstrated when the conditioned stimulus (sound) begins to elicit the same response as the unconditional stimulus (eating) before learning.

The final type of implicit memory is known as priming, or changes in behavior as a result of experiences that have happened frequently or recently. Priming refers both to the activation of knowledge (e.g. we can prime the concept of kindness by presenting people with words related to kindness) and the influence of this activation on behavior (people who are familiar with the are primed with the concept of kindness can act kindly ).

A measure of the impact of priming on implicit memory is the word fragment test, in which a person is asked to fill in missing letters to form words. You can try this yourself: first try to complete the following word fragments, but only work on each for three or four seconds. Can you think of any words quickly?

_ i b _ a _ y

_h_s_ _i_n

_ OK

_ his _

Now read the following sentence carefully:

“He pulled his materials from the shelves, checked them, and then left the building.”

Then try again to form words from the word fragments.

I think you’ll find that it’s easier to complete fragments 1 and 3 as “library” and “book” respectively after reading the sentence than before reading it. However, reading the sentence didn’t really help you complete fragments 2 and 4 as “Doctor” and “Chaise”. This difference in implicit memory is likely due to the fact that when reading the sentence, the concept “library” (and perhaps “book”) was primed, although they were never explicitly mentioned. Once a concept is prepared, it influences our behavior, for example in word fragment tests.

Our everyday behavior is influenced by priming in a wide variety of situations. Seeing a cigarette advertisement can persuade us to start smoking, seeing the flag of our home country can inspire our patriotism, and seeing a student from a rival school can inspire our competitive spirit. And these influences on our behavior can occur without us being aware of it.

Research Focus: Priming Outside Awareness Affects Behavior One of the most important characteristics of implicit memories is that they are often formed and used automatically, without much effort or awareness on our part. In a demonstration of the automaticity and influence of priming effects, John Bargh and his colleagues (Bargh, Chen & Burrows, 1996) conducted a study in which they showed undergraduate students lists of five encoded words to compose each one Sentence. In addition, the words were associated with stereotypes of older people for half of the research participants. These participants saw words like: retirees live in Victoria forgetful bingo man plays The other half of the research participants also formed sentences, but with words that had nothing to do with senior citizen stereotypes. The purpose of this task was to remind some participants of stereotypes about older people but not others. The experimenters then assessed whether priming stereotypes of older people would have an impact on student behavior — and it actually did. When the research participant had gathered all their belongings and thought the experiment was over, the experimenter thanked him or her for participating and directed them to the nearest elevator. Then, unbeknownst to the participants, the experimenters recorded the time the participant spent walking from the experimental room door to the elevator. As you can see in Figure 9.3, “Research results”. Participants who had formed sentences with words related to older stereotypes adopted the behavior of older people – they walked significantly more slowly when they left the test room. To determine whether these priming effects occurred outside of the participants’ awareness, Bargh and his colleagues asked yet another group of students to complete the priming task and then indicate whether the words they used to form the sentences were theirs were in any way related to each other or might have influenced their behavior in any way. These students were unaware of the possibility that the words might have associated with older people or influenced their behavior.

Stages of memory: sensory, short-term and long-term memory

Another way to understand memory is to look at it in stages, which describe the length of time information remains available to us. According to this approach (see Figure 9.4, “Memory Duration”), information begins in sensory memory, moves to short-term memory, and finally to long-term memory. But not all information goes through all three phases; most of it is forgotten. Whether the information is shifted from shorter-duration memory to longer-duration memory, or whether it is completely lost from memory, depends on how the information is treated and processed.

sensory memory

Sensory memory refers to the brief storage of sensory information. Sensory memory is a memory buffer that only lasts for a very short time and then, if ignored and passed on for further processing, falls into oblivion. The purpose of sensory memory is to give the brain some time to process the incoming sensations and allow us to see the world as a continuous stream of events rather than individual parts.

Visual sensory memory is known as iconic memory. Iconic memory was first studied by the psychologist George Sperling (1960). In his research, Sperling showed participants a display of letters in rows similar to that shown in Figure 9.5, “Measuring Iconic Memory”. However, the display only lasted about 50 milliseconds (1/20th of a second). Sperling then gave his participants a memory test in which they were asked to name all the letters they could remember. On average, participants could only remember about a quarter of the letters they saw.

Sperling argued that the participants had seen all of the letters but could only remember them very briefly, making it impossible for them to report them all. To test this idea, in his next experiment, he first showed the same letters, but after the display was removed, he signaled participants to report the letters from either the first, second, or third row. In this state, the participants now reported almost all letters in this row. This finding confirmed Sperling’s suspicion: the participants had access to all the letters in their iconic memories, and if the task was short enough, they could report on the part of the display he asked them to do. The “short enough” is the length of the iconic memory, which turns out to be around 250 milliseconds (¼ second).

Auditory sensory memory is known as echoic memory. Unlike iconic memories, which expire very quickly, echoic memories can last up to four seconds (Cowan, Lichty, & Grove, 1990). This is handy because, among other things, it allows you to remember the words you said at the beginning of a long sentence when you finish it and take notes on your psychology professor’s last statement even after he or she has finished finished saying it.

In some people, iconic memory seems to last longer, a phenomenon known as eidetic imagery (or photographic memory), in which people can report details of an image over long periods of time. These people, who often suffer from mental disorders such as autism, claim that they can “see” an image long after it is presented, and often accurately report on that image. There is also some evidence of eidetic memories in hearing; Some people report that their echo memories last for an unusually long time. The composer Wolfgang Amadeus Mozart may have possessed an eidetic memory for music, for from a very young age and without much musical training he could listen to compositions for long periods and then reproduce them almost perfectly (Solomon, 1995) .

short-term memory

Most information that enters sensory memory is forgotten, but information that we pay attention to in order to remember it can enter short-term memory. Short-term memory (STM) is where small amounts of information can be stored temporarily for more than a few seconds but typically less than a minute (Baddeley, Vallar, & Shallice, 1990). Information in short-term memory is not stored permanently but is available for us to process, and the processes we use to understand, modify, interpret and store information in the STM are called working memory.

Although called memory, working memory is not a memory store like STM, but rather a series of memory procedures or operations. For example, imagine that you are asked to participate in a task like this, which is a measure of working memory (Unsworth & Engle, 2007). Each of the following questions appears individually on a computer screen and then disappears after you answer the question:

Is 10 × 2 − 5 = 15? (Answer YES OR NO) Then remember “S” Is 12 ÷ 6 − 2 = 1? (Answer YES OR NO) Then remember “R” Is 10 × 2 = 5? (Answer YES OR NO) Then remember “P” Is 8 ÷ 2 − 1 = 1? (Answer YES OR NO) Then remember “T” Is 6 × 2 − 1 = 8? (Answer YES OR NO) Then remember “U” Is 2 × 3 − 3 = 0? (Answer YES OR NO) Then remember “Q”

In order to successfully solve the task, you must answer each of the math problems correctly while memorizing the letter that follows the problem. Then, after the six questions, you must list the letters that appeared in each of the trials in the correct order (in this case, S, R, P, T, U, Q).

To complete this difficult task, you will need to use a variety of skills. You clearly need to use STM as you need to keep the letters until you are asked to list them. But you also need a way to make the most of your available attention and processing. For example, you might decide to repeat the letters twice, then quickly solve the next problem, and then repeat the letters twice again, including the new one. Maintaining this strategy (or similar ones) is the role of the central executive of working memory—the part of working memory that controls attention and processing. The central executive will employ whatever strategies seem best for the task at hand. For example, the central executive will control the rehearsal process while instructing the visual cortex to create an image of the list of letters in memory. You can see that although STM is involved, the processes we use to work with the material in memory are also critical.

Short-term memory is limited in both length and the amount of information it can hold. Peterson and Peterson (1959) found that when people were asked to memorize a list of three-letter strings and then immediately asked to perform a distracting task (counting backwards by threes), the material was quickly forgotten (see Figure 9.6, “STM Decay”), so that after 18 seconds it was practically gone.

One way to prevent information from decaying from short-term memory is to use working memory to rehearse it. Maintenance rehearsal is the process of repeating information mentally or aloud with the goal of retaining it in memory. We participate in maintenance rehearsals to keep something we want to remember (such as someone’s name, email address, or phone number) long enough to write it down, use it, or possibly transferred to long-term memory.

If we continue to rehearse information, it will remain in STM until we stop rehearsing it, but there is also a capacity limit for STM. Try to read each of the following rows of numbers row by row at a speed of about one number per second. Then, when you’ve finished each row, close your eyes and write down as many numbers as you can remember.

019

3586

10295

861059

1029384

75674834

657874104

6550423897

If you’re like the average person, you’ll have found that you did pretty well on this test of working memory, known as the digit span test, until about the fourth line, and then you started to have problems . I bet you missed some of the numbers in the last three rows and did pretty badly on the last one.

Most adults’ digit range is between five and nine digits, with an average of about seven. The cognitive psychologist George Miller (1956) referred to “seven plus or minus two” information as the magic number of short-term memory. But if we can only hold a maximum of about nine digits in short-term memory, how can we retain larger amounts of information than that? For example, how can we ever remember a 10-digit phone number long enough to dial it?

One way we can expand our ability to remember things in STM is by using a memory technique called chunking. Chunking is the process of organizing information into smaller groupings (chunks), thereby increasing the number of items that can be stored in STM. For example, try to remember this string of 12 letters:

XOFCBANNCVTM

You probably won’t be able to do that very well because the number of letters is larger than the magic number seven.

Now try again with this:

CTVCBCTSNHBO

Would it help if I pointed out that the material in this string can be broken down into four sets of three letters each? I think so, because then you would only have to remember the names of four TV channels instead of 12 letters. In this case, chunking changes the number of items you need to remember from 12 to just four.

Experts rely on chunking to process complex information. Herbert Simon and William Chase (1973) showed chess masters and chess beginners different positions of pieces on a chessboard for a few seconds each. The experts were much better at memorizing the positions than the novices because they were able to see the ‘big picture’. They didn’t have to memorize the position of each of the pieces individually, but instead divided the pieces into several larger layouts. But when the researchers showed both groups random chess positions—positions that would be very unlikely to occur in real games—both groups performed equally poorly because in this situation the experts lost their ability to organize the arrangements (see Figure 9.7, “Possible and Impossible Chess Positions”). The same goes for basketball. Basketball players remember actual basketball positions much better than non-players, but only when the positions make sense in relation to what is happening on the court or what is likely to happen in the near future and can therefore be broken down into larger chunks (Didierjean & Marmeche , 2005).

When information passes through short-term memory, it can enter long-term memory (LTM), a store that can store information for days, months, and years. Long-term memory capacity is large and there is no known limit to what we can remember (Wang, Liu & Wang, 2003). Though we may forget at least some information after learning it, other things will stay with us forever. In the next section, we will discuss the principles of long-term memory.

KEY FINDINGS Memory refers to the ability to store and recall information over time.

Our memory is very good at some things, but our active cognitive processing of information means that memory is never an exact copy of what we experienced.

Explicit memory refers to experiences that can be intentionally and consciously recalled and is measured by recall, recognition, and relearning. Explicit memory includes episodic and semantic memory.

Measures of relearning (also known as “savings”) assess how much faster information is learned when it is re-studied after it has already been learned but then forgotten.

Implicit memory refers to the influence of experiences on behavior, even when the individual is unaware of those influences. The three types of implicit memory are procedural memory, classical conditioning, and priming.

Information processing begins in sensory memory, moves to short-term memory, and finally to long-term memory.

Maintenance rehearsal and chunking are used to retain information in short-term memory.

Long-term memory capacity is large, and there is no known limit to what we can remember.

Exercises and critical thinking List some situations in which sensory memory is useful to you. What do you think your perception of the stimuli would be like if you had no sensory memory? Describe a situation in which you need to use working memory to complete a task or solve a problem. How does your working memory help you?

references

Atkinson, R.C., & Shiffrin, R.M. (1968). Human Memory: A Proposed System and Its Control Processes. In K. Spence (ed.), The Psychology of Learning and Motivation (Vol. 2). Oxford, England: Academic Press.

Baddeley, A.D., Vallar, G., & Shallice, T. (1990). The development of the concept of working memory: implications and contributions of neuropsychology. In G. Vallar & T. Shallice (eds.), Neuropsychological impairments of short-term memory (pp. 54–73). New York, NY: Cambridge University Press.

Bargh, J.A., Chen, M., & Burrows, L. (1996). Automatism of social behavior: direct effects of trait construct and stereotype activation on action. Journal of Personality and Social Psychology, 71, 230–244.

Bridgeman, B., & Morgan, R. (1996). Success in college for students with discrepancies between performance on multiple choice and essay tests. Journal of Educational Psychology, 88(2), 333–340.

Cowan, N., Lichty, W., & Grove, T.R. (1990). Properties of memory for unsupervised syllables. Journal of Experimental Psychology: Learning, Memory, and Cognition, 16(2), 258–268.

Didierjean, A., & Marmèche, E. (2005). Predictive rendering of visual basketball scenes by novice and experienced players. Visual Perception, 12(2), 265-283.

Haist, F., Shimamura, A.P., & Squire, L.R. (1992). On the relationship between memory and recognition memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18(4), 691–702.

Miller, GA (1956). The Magic Number Seven, Plus or Minus Two: Some Limits to Our Ability to Process Information. Psychological Review, 63(2), 81-97.

Nelson, T.O. (1985). Ebbinghaus’ contribution to retention measurement: Savings in retraining. Journal of Experimental Psychology: Learning, Memory and Cognition, 11(3), 472-478.

Peterson, L. & Peterson, M.J. (1959). Short-term retention of individual verbal items. Journal of Experimental Psychology, 58(3), 193–198.

Simon, H.A. & Chase, W.G. (1973). skill in chess. American Scientist, 61(4), 394-403.

Solomon, M. (1995). Mozart: One Life. New York, NY: Harper Perennial.

Sperling, G. (1960). The available information in a short visual representation. Psychological Monographs, 74(11), 1-29.

Unsworth, N., & Engle, RW. (2007). On the partition of short-term and working memory: An investigation of the simple and complex span and its relation to higher-order abilities. Psychological Bulletin, 133(6), 1038-1066.

Wang Y, Liu D, & Wang Y (2003). The discovery of the capacity of human memory. Brain & Mind, 4(2), 189-198.

image attributions

Figure 9.4: Adapted from Atkinson & Shiffrin (1968).

Figure 9.5: Adapted from Sperling (1960).

Figure 9.6: Adapted from Peterson & Peterson (1959).

Book by Daniel Schachter

The Seven Sins of Memory: How the Mind Forgets and Remembers is a book by Daniel Schachter, former Chair of the Department of Psychology at Harvard University and a leading memory researcher.

The book revolves around the theory that “the seven sins of memory” are similar to the seven deadly sins and that trying not to commit these sins will help improve your ability to remember. Schacter argues that these features of human memory are not necessarily bad and that they serve a useful purpose in memory. For example, persistence is one of the memory sins that can lead to things like post-traumatic stress disorder. However, persistence is also required for long-term memory and is therefore essential.

Overview [ edit ]

Schacter asserts that “the malfunctions of memory can be broken down into seven basic transgressions or ‘sins’.”[1] These are impermanence, distraction, blockage, misattribution, suggestibility, bias, and persistence. The first three are described as sins of omission because the result is not remembering an idea, fact, or event. The other four sins (misattribution, suggestibility, bias, and persistence) are actual sins, meaning there is some form of memory but not the fidelity or facts, events, or ideas desired.

Types of memory errors[edit]

impermanence [edit]

Impermanence refers to the general deterioration of a particular memory over time and is caused by disorders. There are two types of interference: proactive interference (old information inhibits the ability to remember new information) and retroactive interference (new information inhibits the ability to remember old information). Typically, more information can be stored about recent events than about older events. This is especially true for episodic memory compared to semantic memory, since “detailed evocative memories from the past” contain more multidimensional information than “general conceptual knowledge freed from a specific spatiotemporal context”.[2] Because memories of experiences contain a variety of information—including sensory, spatial, and temporal details—there are more areas within an episodic memory that are susceptible to disruption.

One of Schacter’s examples[3] of impermanence is a study[4] of how well students recalled learning of the O.J. Simpson trial verdict immediately, 15 months, and 32 months later. After three years, less than 30 percent remembered it accurately and almost half had serious errors.

In this form of memory breakdown, problems arise at the interface between attention and memory. Common mistakes of this type are misplacing keys or glasses or forgetting appointments because the coding did not pay enough attention to what needs to be remembered later.

Block [ edit ]

Blocking is when the brain is trying to recall or encode information but another memory is interfering. Blocking is a major cause of the tongue-tipping phenomenon (a temporary inaccessibility of stored information).

Incorrect attribution[edit]

Incorrect attribution leads to correct recollection of information with incorrect recollection of the source of that information. For example, a person who witnesses a murder after watching a television show may mistakenly blame someone for the murder they saw on the television show. This fallacy has profound implications in legal systems because of its unacknowledged prevalence and the reliance often placed on an individual’s ability to correctly transmit information critical to the identification of a suspect.

An example that Schacter[5] cites of the misattribution of eyewitnesses occurred in connection with the Oklahoma City bombing in 1995. Two days earlier, the bomber had rented a pickup truck, but an employee there reported seeing two men watching who rented it together. One description matched the actual bomber, but the other description soon became one of two men who also rented a van the next day and had nothing to do with bombing.

Schacter also describes how to use the DRM method to generate mismatch errors. Subjects are read a list of words such as sharp, needle, sewing, etc., but not the word needle. Subsequent subjects are given a second list of words containing the word *needle* and are asked to identify which words were on the first list. Most of the time, subjects confidently claim that *needle* was on the first list.[6]

suggestibility[edit]

Suggestibility is somewhat similar to misattribution but with the inclusion of overt suggestion. It is acceptance of a wrong suggestion made by others. Memories of the past are often affected by the way they are recalled, and when certain aspects that may appear likely to a particular type of memory are subtly emphasized, those emphasized aspects are sometimes included in the memory, whether they are or not occurred. For example, a person sees a crime committed by a red-haired man. Subsequently, after reading in the newspaper that the act was committed by a brown-haired man, the witness “remembers” a brown-haired man instead of a red-haired man.

The work of Loftus and Palmer on guiding questions is an example of such suggestibility.

bias [edit]

The sin of bias is similar to the sin of suggestibility in that current feelings and worldview distort memory of past events. This can refer to specific events and the general idea one has of a particular period of life. Memories encoded with a certain amount of stimulation and emotion are more easily recalled. For example, a content adult might look back on their childhood with affection, prompted by positive memories of that time that may not be representative of their average childhood mood.

persistence [edit]

This failure of the memory system involves the involuntary retrieval of disruptive information. The memory can range from a mistake at work to a truly traumatic experience, and the persistent memory can lead to the formation of phobias, PTSD, and in particularly disturbing or intrusive cases, even suicide.

Seven Penances[ edit ]

In 2004, while attending a science conference in Orlando, Fla., Scott S. Haraburda overheard the author present these seven sins to U.S. Army scientists and program managers. After conducting several experiments to corroborate Schacter’s identification of these fundamental transgressions, Haraburda developed measures to help us improve our memory, which he termed “atonement”:[7][8]

Find out quickly after an event when it’s fresh in people’s minds. Use a prioritized to-do list. Take notes of important events, including meeting minutes. Record important events and milestones on a daily basis. Use neutral questions when asking for information. Understand the basis or perspective of the person providing the information. Understand and recognize the symptoms of PTS.

A surgical team closes an abdominal incision, successfully completing a difficult operation. Weeks later, the patient comes to the emergency room complaining of abdominal pain, and an x-ray shows that one of the forceps used in the operation was left in the patient. Why should highly skilled professionals forget to perform a simple task that they have previously performed thousands of times with ease?

These types of mistakes occur in professions as diverse as aviation and computer programming, but research in psychological science shows that these mistakes may not stem from carelessness or lack of skill, but rather from errors in prospective memory.

In an article in the August issue of Current Directions in Psychological Science, a journal of the Association for Psychological Science, R. Key Dismukes, a scientist at the NASA Ames Research Center, reviews the rapidly growing field of prospective memory research and highlights the highlights different ways in which features of everyday tasks interact with normal cognitive processes to produce memory lapses that sometimes have catastrophic consequences.

Prospective memory errors typically occur when we intend to do something later, become preoccupied with various other tasks, and lose focus on what we originally intended. Despite the name, prospective memory actually depends on several cognitive processes, including planning, attention, and task management. These memory lapses, which are common in everyday life, are usually annoying, but can have tragic consequences. “Every summer, several small children die in hot cars when the parents get out of the car and forget that the child is sleeping peacefully in the back seat,” Dismukes points out.

Many examples of prospective memory involve intending to do something at a specific time, such as going to a doctor’s appointment, or on a specific occasion, such as congratulating a friend the next time you see her. However, much of what we intend to do in our day-to-day lives, whether at home or at work, involves habitual tasks that become repetitive over time. And when it comes to these kinds of habitual tasks, our intentions may not be clear. For example, we don’t usually have an explicit intention to put the key in the ignition every time we drive a car—the intention is built into our usual routine of driving.

In previous research, Dismukes and colleagues identified several types of situations that can lead to predictive memory loss. They found out that interruptions and disturbances in familiar processes, which are already irritating enough in everyday life, can be fatal in some professional fields. In fact, several aircraft disasters have occurred because pilots were interrupted while performing critical pre-flight tasks – after the interruption was over, pilots would jump to the next task without realizing that the interrupted tasks were not yet completed.

With all the negative attention multitasking has received in recent years, it’s perhaps no surprise that multitasking is also a major cause of potential memory loss. We seem to have gotten pretty used to juggling multiple tasks at once. However, research shows that when a problem arises with any task we are currently concentrating on, we become prone to cognitive tunneling and forgetting to bring our attention back to the other tasks at hand.

To defend against potential memory loss and its potentially catastrophic consequences, aviation and medical professionals now rely on specific memory tools, including checklists. Research also shows that implementation intentions, which indicate when and where a specific intention will be executed, can help prevent such mistakes in everyday life. Dismukes notes that this type of specific plan has been shown to improve predicted memory performance by two to four times on tasks such as exercising, taking medication, breast self-examination, and doing homework.

In addition to checklists and implementation intentions, Dismukes and others have highlighted several other measures that can help remember and carry out intended actions:

Use external reminders such as the notification calendar on the cell phone

Avoid multitasking if one of your tasks is critical

Get important tasks done now instead of putting them off until later

Create reminder cues that stand out and place them in a hard-to-miss spot

Link the goal task to a habit you’ve already established

“Rather than blaming individuals for unintentional errors in prospective memory, organizations can improve safety by supporting the application of these measures,” argues Dismukes. He suggests that scientists should combine laboratory research with observations of human performance in real-world settings to better understand how prospective memory works and to develop practical strategies to avoid making mistakes.

Coding visual images is the process of storing new information by converting it into mental images. First, encoding visual images does some of the same things as semantic encoding: When you create a visual image, you relate incoming information to knowledge already in memory. Second, when you use visual imagery to encode words and other verbal information, you end up with two different mental placeholders for the items; one visual and one verbal. This gives you more ways to remember them than just a verbal placeholder alone. The occipital lobe

Type of human long-term memory

Explicit memory (or declarative memory) is one of the two main types of human long-term memory, the other being implicit memory. Explicit memory is the conscious, intentional recollection of factual information, past experiences, and concepts.[1] This type of memory depends on three processes: acquisition, consolidation, and retrieval.[2][3] Explicit memory can be divided into two categories: episodic memory, which stores specific personal experiences, and semantic memory, which stores factual information.[4] Explicit memory requires stepwise learning with multiple presentations of a stimulus and response.

The opposite of explicit memory is implicit memory, which refers to unconsciously acquired and used memories such as skills (e.g. knowing how to dress) or cognition. Unlike explicit memory, implicit memory learns quickly, even from a single stimulus, and is influenced by other mental systems.

Sometimes a distinction is made between explicit memory and declarative memory. In such cases, explicit memory refers to any type of conscious memory, and declarative memory refers to any type of memory that can be described in words; However, if one assumes that a memory cannot be described without consciousness and vice versa, then the two concepts are identical.

Types [ edit ]

Episodic memory[edit]

Episodic memory consists of storing and remembering observational information associated with specific life events. These can be memories that happened directly to the subject, or just memories of events that happened around them. Episodic memory is what people generally think of when they talk about memory. Episodic memory allows for the retrieval of various contextual and situational details of previous experiences.

Some examples of episodic memory are remembering when you first entered a specific classroom, remembering to leave your carry-on bag when boarding an airplane, en route to a specific destination on a specific day and time, remembering being notified of someone being fired from their job, or remembering having told a subordinate that they would be fired from their job. The retrieval of these episodic memories can be thought of as the process of mentally reliving the past events affecting them in detail.[4] Episodic memory is believed to be the system that provides the basic support for semantic memory.

Semantic memory[edit]

Semantic memory refers to general world knowledge (facts, ideas, meanings, and concepts) that can be articulated and is independent of personal experiences.[5] These include world knowledge, object knowledge, language skills, and conceptual priming. Semantic memory differs from episodic memory, which is the memory of experiences and specific events that occur during people’s lives, of which they can be recomposed at any given point in time.[6] For example, semantic memory may contain information about what a cat is, while episodic memory may contain a specific memory of petting a particular cat. People can learn new concepts by applying what they have learned in the past.[7]

Other examples of semantic memory are foods, capitals of a geographic region, facts about people, dates, or the lexicon of a language, such as B. a person’s vocabulary.[4]

Hybrid types[ edit ]

Autobiographical memory is a memory system consisting of episodes remembered from a person’s life based on a combination of episodic (personal experiences and specific objects, people and events experienced at a specific time and place ) and semantic (general knowledge and facts about the world) memory .[8]

Spatial memory is the part of memory responsible for recording information about one’s environment and spatial orientation. For example, a person’s spatial memory is required to navigate a familiar city, just as a rat’s spatial memory is required to learn the position of food at the end of a maze. It is often argued that in both humans and animals, spatial memories are summarized as a cognitive map. Spatial memory has representations in working, short-term, and long-term memory. Research shows that there are specific areas of the brain that are linked to spatial memory. Many methods are used to measure spatial memory in children, adults, and animals.

Examples[edit]

Long-term memory Subtype Description Example Declarative (explicit) Conscious remembering of facts and events Semantic Factual information The capital of Germany is Berlin Episodic Specific personal experiences Your 10th birthday Non-declarative (implicit) Forms of learning that are unconscious – learning to achieve a sequence of actions that do not necessarily elicit knowledge. This priming differs from priming in psychology. If you could get a picture of half of a letter of the alphabet and recognize which letter it was, you could complete the letter. Perceptual learning Perceptual ability to differentiate sensory perceptions through the experience of stimuli Distinguishing between categories such as smells, colors, tastes Category learning “…the process of establishing a memory trail that improves the efficiency of assigning novel objects to contrasting groups” [9] film genres, dog breeds , Fruit Varieties Emotional Learning “…preservation of classically conditioned emotional relationships that cannot be voluntarily recalled or reported”[ citation needed ] Being afraid of dogs but not explaining why Procedural Learning The formation of skills and habits Learning to ride a bike

The language model[ edit ]

Declarative and procedural memory fall into two categories of human language. The declarative storage system is used by the lexicon. Declarative memory stores all arbitrary, unique word-specific knowledge, including word meanings, wording, and abstract representations such as word categories. In other words, random bits and pieces of knowledge about language that are specific and unpredictable are stored in declarative memory. Declarative memory includes representations of simple words (e.g., cat), bound morphemes (morphemes that must belong together), irregular morphological forms, verb complements, and idioms (or non-compositional semantic units). Irregular morphological structures fall into the declarative system; the irregularities (like went the past tense of go or idioms) are what we need to remember.

Declarative memory supports an associative superposition memory that allows for generalizations across representations. For example, memorizing phonologically similar stem-irregular past tense pairs (z -jumped). This ability to generalize may underlie some level of productivity within the memory system.

While declarative memory deals with irregularities in morphology, procedural memory uses regular phonology and regular morphology. The procedural memory system is used by the grammar, where the grammar is defined by building a rule-driven structure. The language’s ability to use grammar comes from procedural memory, making grammar a different procedure. It underlies the learning of new and already learned rule-based techniques that monitor the regularities of language, particularly those techniques that relate to the combining of elements into complex structures that have precedence and hierarchical relationships—precedence in the left-to-right sense and hierarchically in the feeling from top to bottom. Procedural memory builds a rule-driven structure (merging or series) of shapes and representations into complex structures such as:

Phonology Inflectional and derivational morphology Compositional semantics (the meaning of assembling words into complex structures) Syntax

Broca and Wernicke’s brain region

Broca’s area is important for procedural memory because “Broca’s area is involved in the expressive aspects of spoken and written language (production of sentences constrained by the rules of grammar and syntax).”[10] The Broca -Area corresponds to parts of the inferior frontal gyrus, probably Brodmann’s area 44 and 45. Procedural memory is affected in Broca’s aphasia. Agrammatism is evident in patients with Broca’s aphasia, who present with lack of fluency and omission of morphology and function words. While those with Broca’s aphasia are still able to comprehend or comprehend language, they have difficulty producing it. Language production becomes more difficult when sentences are complex; For example, the passive voice is a grammatically complex structure that is harder to understand for people with Broca’s aphasia. Wernicke’s area is critical to language development and focuses on language comprehension rather than language production. Wernicke’s aphasia affects declarative memory. In contrast to Broca’s aphasia, paragrammatism is evident, leading to normal or excessive fluency and use of inappropriate words (neologisms). Those with Wernicke’s aphasia have trouble understanding the meaning of words and may not recognize their speech defects.

history [edit]

Research into human memory goes back over the last 2000 years. An early attempt to understand memory can be found in Aristotle’s major treatise On the Soul, in which he compares the human mind to a blank slate.[11] He theorized that all human beings are born devoid of any knowledge and are the sum of their experiences. However, it was not until the late 19th century that a young German philosopher named Herman Ebbinghaus developed the first scientific approach to the study of memory.[12] While some of his findings endure and are still relevant today (learning curve), his greatest contribution to the field of memory research was proving that memory can be studied scientifically. In 1972, Endel Tulving proposed the distinction between episodic and semantic memory.[4] This was quickly adopted and is now widely accepted. Subsequently, in 1985, Daniel Schacter proposed a more general distinction between explicit (declarative) and implicit (procedural) memory[13]. With recent advances in neuroimaging technology, there have been a variety of findings linking specific brain areas to declarative memory. Despite these advances in cognitive psychology, there is still much to be discovered regarding the working mechanisms of declarative memory.[14] It is unclear whether declarative memory is mediated by a particular memory system or whether it is more precisely classified as a type of knowledge, and it is not known how or why declarative memory evolved in the first place.[14]

Neuropsychology[ edit ]

Normal brain function[ edit ]

hippocampus [edit]

Hippocampus as seen in red

Although many psychologists believe that the entire brain is involved in memory, the hippocampus and surrounding structures appear to be most important specifically in declarative memory.[15] The ability to retain and recall episodic memories is highly dependent on the hippocampus,[15] while the formation of new declarative memories is dependent on both the hippocampus and the parahippocampus.[16] Other studies have found that the parahippocampal cortices are associated with superior recognition memory.[16]

The three-stage model was developed by Eichenbaum, et al. (2001) and proposes that the hippocampus does three things with episodic memory:

Conveys the recording of episodic memories Identifies commonalities between episodes Links these common episodes into a memory area.

To support this model, a version of Piaget’s Transitive Inference Task was used to show that the hippocampus is actually used as a storage space.[15]

When we experience an event for the first time, a connection is made in the hippocampus that allows us to remember that event in the future. Separate links are also created for functions related to this event. For example, if you meet someone new, a unique link will be created for them. Additional links are then connected to that person’s link so you can remember what color their shirt was, what the weather was like when you met them, etc. Certain episodes are easier to remember and recall by repeating yourself to them exposes (which is the links in the memory area) that allow for faster retrieval when remembered.[15]

Hippocampal cells (neurons) are activated based on the information they are exposed to. Some cells are specific for spatial information, certain stimuli (smells, etc.), or behaviors, as shown in a Radial Maze Task.[15] It is therefore the hippocampus that allows us to recognize certain situations, environments, etc. as different or similar to others. However, the three-stage model does not take into account the importance of other cortical structures in memory.

The anatomy of the hippocampus is largely conserved among mammals, and the role of these areas in declarative memory is also conserved among all species. The organization and neural pathways of the hippocampus are very similar in humans and other mammalian species. In humans and other mammals, a cross section of the hippocampus reveals the dentate gyrus and the dense cell layers of the CA fields. The intrinsic connectivity of these areas is also preserved.[17]

Results of an experiment by Davachi, Mitchell, and Wagner (2003) and subsequent research (Davachi, 2006) indicate that activation in the hippocampus during encoding is related to a subject’s ability to recall past events or later relational memories. These tests did not distinguish between individual test items seen later and forgotten.[18][19]

Prefrontal Cortex[ edit ]

The lateral prefrontal cortex (PFC) is essential for remembering contextual details of an experience and not for memory formation.[16] The PFC is also more involved in episodic memory than in semantic memory, although it plays a small role in semantics.[20]

Using PET studies and verbal stimuli, Endel Tulving found that remembering is an automatic process.[21] It is also well documented that hemispheric asymmetry occurs in the PFC: during memory encoding, the left dorsolateral PFC (LPFC) is activated, and during memory retrieval, activation in the right dorsolateral PFC (RPFC) is observed.[21]

Studies have also shown that the PFC is strongly involved in autonoetic consciousness (see Tulving’s theory).[22] This is responsible for the memory experiences and the human ability to “mental time travel” (characteristics of episodic memory).

Amygdala as seen in red

Amygdala[ edit ]

The amygdala is thought to be involved in encoding and retrieving emotionally charged memories. Much of the evidence for this comes from research into a phenomenon known as flashbulb memories. These are cases where memories of strong emotional events are more detailed and enduring than normal memories (e.g. 9/11 attacks, JFK assassination). These memories have been linked to increased activation in the amygdala.[23] Recent studies of patients with damage to the amygdala suggest that it is involved in memory for general knowledge rather than specific information.[24][25]

Other structures involved[ edit ]

The diencephalon regions have shown brain activation when a distant memory is recalled[20], and the occipital lobe, ventral temporal lobe, and fusiform gyrus all play a role in memory formation.[16]

Lesion Studies[ edit ]

Lesion studies are commonly used in cognitive neuroscience research. Lesions can arise naturally from trauma or disease, or they can be surgically induced by researchers. When studying declarative memory, the hippocampus and the amygdala are two structures that are often examined using this technique.

Studies on lesions of the hippocampus[edit]

The Morris water maze

The Morris water navigation task tests spatial learning in rats.[26] In this test, rats learn to escape from a pool by swimming to a platform that is just below the water’s surface. Visual cues surrounding the pool (such as a chair or a window) help the rat locate the platform on subsequent trials. The rats’ use of specific events, cues, and locations are all forms of declarative memory.[27] Two groups of rats are observed: a control group with no lesions and an experimental group with hippocampal lesions. In this task, created by Morris, rats are placed in the same position in the pool for 12 trials. Each trial is timed and the distance traveled by the rats is recorded. Rats with hippocampal lesions successfully learn to find the platform. When the starting point is shifted, the rats with hippocampal lesions typically cannot localize the platform. However, the control rats are able to find the platform using the cues they received during the learning experiments.[26] This demonstrates the involvement of the hippocampus in declarative memory.[27]

The odor recognition task developed by Bunsey and Eichenbaum involves a social encounter between two rats (a subject and a demonstrator). After eating a particular type of food, the demonstrator interacts with the experimental rat, which then smells the odor of food on the breath of the others. The experimenters then present the experimental rat with a choice between two diet options; the food previously eaten by the demonstrator and a novel food. The researchers found that both control and lesioned rats chose the familiar food when there was no time lag. However, after 24 hours, the rats with hippocampal lesions were equally likely to eat both types of food, while the control rats chose the known food.[28] This can be attributed to the inability to form episodic memories due to lesions in the hippocampus. The implications of this study can be observed in people with amnesia, pointing to the role of the hippocampus in the development of episodic memories that can be generalized to similar situations.[27]

Henry Molaison, formerly known as H.M., had portions of his left and right medial temporal lobes (hippocampi) removed, resulting in loss of the ability to form new memories.[29] Long-term declarative memory was critically affected when the structures were removed from the medial temporal lobe, including the ability to form new semantic knowledge and memories.[30] The disconnection between acquisition of declarative memory and other types of learning in Molaison was originally observed in motor learning.[31] Molaison’s declarative memory was not working, as could be seen when Molaison completed the repetition priming task. His performance improved over the course of the trials, but his results were inferior to controls.[32] In Molaison’s state, the same results from this priming task are reflected when looking at the other basic memory functions such as remembering, remembering, and recognizing.[29] Lesions should not be interpreted as an all-or-nothing condition, in Molaison’s case not all memory and cognition is lost, although declarative memory is severely damaged, he still has a sense of self and memories developed before the lesion occurred.[33]

Patient R.B. was another clinical case that reinforced the role of the hippocampus in declarative memory. After suffering an ischemic episode during cardiac bypass surgery, patient R.B. awoke with severe anterograde amnesia. IQ and cognition were not affected, but declarative memory deficits were observed (though not to the extent seen in Molaison). After death, an autopsy revealed that patient R.B. had bilateral lesions of the CA1 cell region along the entire length of the hippocampus.

Amygdala lesion studies [ edit ]

Adolph, Cahill, and Schul completed a study showing that emotional arousal facilitates the encoding of material into long-term declarative memory.[34] They selected two subjects with bilateral amygdala damage, six control subjects, and six subjects with brain damage. All subjects were shown a series of twelve slides accompanied by a narration. The slides differed in the degree to which they evoked emotion – slides 1 to 4 and slides 9 to 12 contain non-emotional content. Slides 5 through 8 contain emotional material, and slide seven contained the most emotionally arousing image and description (an image of a car accident victim’s legs that were surgically repaired).[34]

The emotionally arousing slide (slide 7) was no better remembered by participants with bilateral damage than any of the other slides. In particular, all other participants remembered the seventh slide best and most extensively of all the other slides.[34] This shows that the amygdala is necessary to facilitate the encoding of declarative knowledge about emotionally arousing stimuli, but not for the encoding of knowledge about emotionally neutral stimuli.[35]

Factors affecting declarative memory

stress [edit]

Stress can affect declarative memory recall. Lupie et al. completed a study in which participants could participate in 3 phases. Phase 1 involved memorizing a set of words, Phase 2 involved either a stressful (public speaking) or non-stressful situation (an attention task), and Phase 3 required participants to remember the words they learned in Phase 1. There were signs of reduced declarative memory in participants who had to stop the stressful situation after learning the words.[36] Overall, memory performance after the stressful situation was worse than after the non-stressful situation. It was also found that performance differed according to whether the participant responded to the stressful situation with an increase in measured salivary cortisol levels.

Post-Traumatic Stress Disorder (PTSD) occurs after exposure to a traumatic event that causes fear, horror, or helplessness associated with physical harm, threat of harm, or death to oneself or another.[37] Chronic stress in PTSD contributes to an observed decrease in hippocampal volume and declarative memory deficits.[38]

Stress can alter memory functions, reward, immune function, metabolism, and susceptibility to various diseases.[39] Illness risk is particularly relevant to mental illness, with chronic or severe stress remaining a common risk factor for several mental illnesses.[40] One system proposes that there are five types of stress, termed acute temporary stressors, brief naturalistic stressors, distressing event sequences, chronic stressors, and remote stressors. An acute temporary stressor involves a short-term challenge, while a brief natural stressor involves a normal yet challenging event. A stressful sequence of events is a stressor that occurs and then continues to cause stress into the immediate future. A chronic stressor involves exposure to a long-term stressor, and a distant stressor is a stressor that is not immediate.[41]

Neurochemical stressors on the brain

Cortisol is the primary glucocorticoid in the human body. In the brain, it modulates the ability of the hippocampus and prefrontal cortex to process memories.[42] Although the exact molecular mechanism of how glucocorticoids affect memory formation is unknown, the presence of glucocorticoid receptors in the hippocampus and prefrontal cortex tells us that these structures are some of its many targets.[42] Cortisone, a glucocorticoid, has been shown to impair blood flow in the right parahippocampal gyrus, left visual cortex, and cerebellum.[42]

A study by Damoiseaux et al. (2007) assessed the effects of glucocorticoids on hippocampal and prefrontal cortex activation during declarative memory retrieval. They found that giving participants hydrocortisone (the term for cortisol when used as a drug) an hour before information retrieval impaired free word recall, but when it was given before or after learning, it did it has no effect on memory.[42] They also found that hydrocortisone decreased brain activity in the above areas during declarative memory retrieval.[42] Therefore, naturally occurring cortisol elevations during periods of stress lead to impairment of declarative memory.[42]

It is important to note that only male subjects participated in this study, which may be significant since sex steroid hormones can have different effects in response to cortisol administration. Men and women also respond differently to emotional stimuli, which can affect cortisol levels. This was also the first functional magnetic resonance imaging (fMRI) study performed using glucocorticoids, so further investigations are needed to further substantiate these results.[42]

Consolidation during sleep[edit]

Sleep is thought to play an active role in consolidating declarative memory. In particular, the unique properties of sleep enhance memory consolidation, such as: B. the reactivation of newly learned memories during sleep. For example, it has been proposed that the central mechanism for the consolidation of declarative memory during sleep is the reactivation of hippocampal memory representations. This reactivation transmits information to neocortical networks where it is integrated into long-term representations.[43] Studies in rats involving maze learning revealed that neural assemblies in the hippocampus that are used to encode spatial information are reactivated in the same temporal order.[44] Similarly, positron emission tomography (PET) has demonstrated hippocampal reactivation during deep sleep (SWS) following spatial learning.[45] Together, these studies show that newly learned memories are reactivated during sleep, and through this process new memory traces are consolidated.[46] In addition, researchers have identified three types of sleep (SWS, sleep spindle, and REM) in which declarative memory is consolidated.

Slow sleep, often referred to as deep sleep, plays the most important role in consolidating declarative memory, and there is a wealth of evidence to support this claim. Eine Studie ergab, dass die ersten 3,5 Stunden Schlaf die größte Leistungssteigerung bei Gedächtnisabrufaufgaben bieten, da die ersten paar Stunden von SWS dominiert werden. Zusätzliche Schlafstunden tragen nicht zum anfänglichen Leistungsniveau bei. Daher deutet diese Studie darauf hin, dass vollständiger Schlaf für eine optimale Gedächtnisleistung möglicherweise nicht wichtig ist.[47] Eine andere Studie zeigt, dass Menschen, die in der ersten Hälfte ihres Schlafzyklus SWS erlebten, im Vergleich zu Personen, die dies nicht taten, sich besser an Informationen erinnerten. Dies gilt jedoch nicht für Personen, die für die zweite Hälfte ihres Schlafzyklus getestet wurden, da sie weniger SWS erfahren.[48]

Ein weiterer wichtiger Beweis für die Beteiligung von SWS an der Konsolidierung des deklarativen Gedächtnisses ist der Befund, dass Menschen mit pathologischen Schlafzuständen wie Schlaflosigkeit sowohl eine Verringerung des Slow-Wave-Schlafs als auch eine beeinträchtigte Konsolidierung des deklarativen Gedächtnisses während des Schlafs aufweisen.[49] Eine andere Studie fand heraus, dass Menschen mittleren Alters im Vergleich zu jüngeren eine schlechtere Abrufbarkeit von Erinnerungen hatten. Dies deutete wiederum darauf hin, dass SWS mit einer schlechten deklarativen Gedächtniskonsolidierung assoziiert ist, aber nicht mit dem Alter selbst.[50]

Einige Forscher vermuten, dass die Schlafspindel, ein Ausbruch von Gehirnaktivität, der während des Schlafstadiums 2 auftritt, eine Rolle bei der Förderung der Konsolidierung deklarativer Erinnerungen spielt.[51] Kritiker weisen darauf hin, dass die Spindelaktivität positiv mit der Intelligenz korreliert.[52] Im Gegensatz dazu weisen Schabus und Gruber darauf hin, dass sich die Aktivität der Schlafspindel nur auf die Leistung auf neu erlernten Erinnerungen und nicht auf die absolute Leistung bezieht. Dies stützt die Hypothese, dass die Schlafspindel dabei hilft, aktuelle Gedächtnisspuren zu konsolidieren, aber nicht die Gedächtnisleistung im Allgemeinen.[53] Die Beziehung zwischen Schlafspindeln und deklarativer Gedächtniskonsolidierung ist noch nicht vollständig geklärt.[53]

Es gibt eine relativ kleine Menge an Beweisen, die die Idee unterstützen, dass der REM-Schlaf hilft, hochemotionale deklarative Erinnerungen zu konsolidieren. Zum Beispiel Wagner et al. Vergleich der Gedächtnisleistung für emotionalen versus neutralen Text über zwei Instanzen; Frühschlaf, der von SWS dominiert wird, und Spätschlaf, der von der REM-Phase dominiert wird.[54] Diese Studie fand heraus, dass der Schlaf die Erinnerung an emotionalen Text nur während der späten Schlafphase verbesserte, die hauptsächlich REM war. In ähnlicher Weise haben Hu & Stylos-Allen et al. führte eine Studie mit emotionalen versus neutralen Bildern durch und kam zu dem Schluss, dass der REM-Schlaf die Konsolidierung emotionaler deklarativer Erinnerungen erleichtert.[55]

Die Ansicht, dass Schlaf eine aktive Rolle bei der deklarativen Gedächtniskonsolidierung spielt, wird nicht von allen Forschern geteilt. Zum Beispiel Ellenbogen, et al. argumentieren, dass Schlaf das deklarative Gedächtnis aktiv vor assoziativer Interferenz schützt.[56] Darüber hinaus glaubt Wixted, dass die einzige Rolle des Schlafs bei der deklarativen Gedächtniskonsolidierung nichts anderes ist, als ideale Bedingungen für die Gedächtniskonsolidierung zu schaffen.[57] Zum Beispiel werden Menschen im Wachzustand mit geistiger Aktivität bombardiert, was eine effektive Konsolidierung stört. Während des Schlafs jedoch, wenn die Interferenz minimal ist, können Erinnerungen ohne assoziative Interferenz konsolidiert werden. Es bedarf weiterer Forschung, um eine eindeutige Aussage darüber treffen zu können, ob Schlaf günstige Bedingungen für die Konsolidierung schafft oder aktiv die deklarative Gedächtniskonsolidierung fördert.[46]

Kodierung und Abruf [ bearbeiten ]

Die Kodierung des expliziten Gedächtnisses hängt von einer konzeptionell gesteuerten Top-Down-Verarbeitung ab, bei der ein Subjekt die Daten neu organisiert, um sie zu speichern.[58] Das Subjekt stellt Assoziationen mit zuvor verwandten Reizen oder Erfahrungen her.[59] Dies wurde von Fergus Craik und Robert Lockhart als Deep Encoding bezeichnet.[60] So bleibt eine Erinnerung länger bestehen und bleibt in guter Erinnerung. Der spätere Abruf von Informationen wird also stark von der Art und Weise beeinflusst, wie die Informationen ursprünglich verarbeitet wurden.[58]

Der Effekt der Verarbeitungstiefe ist die Verbesserung der nachträglichen Erinnerung an einen Gegenstand, über dessen Bedeutung oder Form eine Person nachgedacht hat. Einfach ausgedrückt: Um explizite Erinnerungen zu schaffen, müssen Sie etwas mit Ihren Erfahrungen tun: darüber nachdenken, darüber sprechen, sie aufschreiben, sie studieren usw. Je mehr Sie tun, desto besser werden Sie sich erinnern. Das Testen von Informationen während des Lernens hat auch gezeigt, dass es die Kodierung im expliziten Gedächtnis verbessert. Wenn ein Schüler ein Lehrbuch liest und sich danach selbst testet, verbessert sich sein semantisches Gedächtnis für das Gelesene. Diese Studie – Testmethode verbessert die Kodierung von Informationen. Dieses Phänomen wird als Testing Effect bezeichnet.[61]

Abruf: Da eine Person eine aktive Rolle bei der Verarbeitung expliziter Informationen gespielt hat, können die internen Hinweise, die bei der Verarbeitung verwendet wurden, auch verwendet werden, um spontane Rückrufe auszulösen.[58] Wenn jemand über ein Erlebnis spricht, helfen die Worte, die er verwendet, wenn er versucht, sich später an dieses Erlebnis zu erinnern. The conditions in which information is memorized can affect recall. If a person has the same surroundings or cues when the original information is presented, they are more likely to remember it. This is referred to as encoding specificity and it also applies to explicit memory. In a study where subjects were asked to perform a cued recall task participants with a high working memory did better than participants with a low working memory when the conditions were maintained. When the conditions were changed for recall both groups dropped. The subjects with higher working memory declined more.[62] This is thought to happen because matching environments activates areas of the brain known as the left inferior frontal gyrus and the hippocampus.[63]

Neural structures involved [ edit ]

Several neural structures are proposed to be involved in explicit memory. Most are in the temporal lobe or closely related to it, such as the amygdala, the hippocampus, the rhinal cortex in the temporal lobe, and the prefrontal cortex.[58] Nuclei in the thalamus also are included, because many connections between the prefrontal cortex and temporal cortex are made through the thalamus.[58] The regions that make up the explicit memory circuit receive input from the neocortex and from brainstem systems, including acetylcholine, serotonin, and noradrenaline systems.[64]

Traumatic brain injury [ edit ]

While the human brain is certainly regarded for its plasticity, there is some evidence that shows traumatic brain injury (TBI) in young children can have negative effects on explicit memory. Researchers have looked at children with TBI in early childhood (i.e. infancy) and late childhood. Findings showed that children with severe TBI in late childhood experienced impaired explicit memory while still maintaining implicit memory formation. Researchers also found that children with severe TBI in early childhood had both increased chance of having both impaired explicit memory and implicit memory. While children with severe TBI are at risk for impaired explicit memory, the chances of impaired explicit memory in adults with severe TBI is much greater.[65]

Memory loss [ edit ]

Alzheimer’s disease has a profound effect on explicit memory. Mild cognitive impairment is an early sign of Alzheimer’s disease. People with memory conditions often receive cognitive training. When an fMRI was used to view brain activity after training, it found increased activation in various neural systems that are involved with explicit memory.[66] People with Alzheimer’s have problems learning new tasks. However, if the task is presented repeatedly they can learn and retain some new knowledge of the task. This effect is more apparent if the information is familiar. The person with Alzheimer’s must also be guided through the task and prevented from making errors.[67] Alzheimer’s also has an effect on explicit spatial memory. This means that people with Alzheimer’s have difficulty remembering where items are placed in unfamiliar environments.[68] The hippocampus has been shown to become active in semantic and episodic memory.[69]

The effects of Alzheimer’s disease are seen in the episodic part of explicit memory. This can lead to problems with communication. A study was conducted where Alzheimer’s patients were asked to name a variety of objects from different periods. The results shown that their ability to name the object depended on frequency of use of the item and when the item was first acquired.[70] This effect on semantic memory also has an effect on music and tones. Alzheimer’s patients have difficulty distinguishing between different melodies they have never heard before. People with Alzheimer’s also have issues with picturing future events. This is due to a deficit in episodic future thinking.[71] There are many other reasons why adults and others may begin to have memory loss.

In popular culture[edit]

Amnesiacs are frequently portrayed in television and movies. Some of the better-known examples include:

In the romantic comedy 50 First Dates (2004), Adam Sandler plays veterinarian Henry Roth, who falls for Lucy Whitmore, played by Drew Barrymore. Having lost her short-term memory in a car crash, Lucy can only remember the current day’s events until she falls asleep. When she wakes up the next morning, she has no recollection of the previous day’s experiences.[72] These experiences would normally be transferred into declarative knowledge, allowing them to be recalled in the future. Although this movie is not the most accurate representation of a true amnesic patient, it is useful for informing viewers of the detrimental effects of amnesia.

Memento (2000) a film inspired by the case of Henry Molaison (H.M.).[73] Guy Pearce plays an ex-insurance investigator suffering from severe anterograde amnesia caused by a head injury. Unlike most amnesiacs, Leonard retains his identity and the memories of events that occurred before the injury, but loses all ability to form new memories. This loss of ability to form new memories indicates that the head injury affected the medial temporal lobe of the brain resulting in the inability for Leonard to form declarative memory.

Finding Nemo features a reef fish named Dory with an inability to develop declarative memory. This prevents her from learning or retaining any new information such as names or directions. The exact origin of Dory’s impairment is not mentioned in the film, but her memory loss accurately portrays the difficulties facing amnesiacs.[72]

See also[edit]

Frank, an alcoholic, claims he hid his stash of alcohol to keep him from drinking and can’t remember where he put it when sober. But when he’s drunk again, he remembers exactly where he put it and can get it out. This is an example of:

Deidre has a list of medicines to buy at a drugstore. She quickly goes through the list and, believing she has memorized it, leaves the list behind when she leaves her house. When she reaches the pharmacy, however, she can only remember the names of the first and last drugs on the list. Deidre’s inability to remember the names of the drugs in the middle of the list is an example

multiple selection

Jeremy visits a new coffee shop. Even though the seating and counter layout at this café is different from any other café he has been to, he automatically knows to queue up at the counter and get his sugar and cream from the side counter . In this scenario, Jeremy has a _____ for how coffee shops work.

What is anterograde amnesia?

Anterograde amnesia is a condition in which a person is unable to create new memories after an amnesia-causing event. Anterograde amnesia can involve either partial or complete inability to remember events. A person with this type of amnesia has intact long-term memories from before the incident.

Anterograde amnesia is thought to involve a failure to encode (or possibly retrieve) new memories. There are also different degrees of severity in anterograde amnesia.

For example, some people might forget a recent meal or a new phone number, while others might forget what they did 30 seconds ago. Task difficulty can also affect memory, with more complex tasks being harder to remember than simpler tasks, which may require less brain power.

What is anterograde memory? The American Psychological Association defines anterograde memory as “the ability to retain events, experiences, and other information after a specific point in time.”

There are several well-known film characters with anterograde amnesia, as the short-term memory deficit can make for some funny and suspenseful scenes. Unfortunately, the true nature of the condition can be highly debilitating.

Take, for example, the character Leonard Shelby in the movie Memento. He takes notes to keep track while trying to solve a crime despite his anterograde amnesia. “Memento” is possibly the best representation of what actual anterograde amnesia is, especially given the way the film is shot to reflect the character’s memory impairments.

memory and amnesia

It can be helpful to understand the different types of memory that can be affected in amnesia. First, we can divide memory into declarative and non-declarative.

Declarative memory refers to remembering facts, whether as part of a specific event or just as unrelated information.

refers to remembering facts, whether as part of a specific event or just unrelated information. Non-declarative memory is also known as procedural memory and refers to remembering how to do something, e.g. B. riding a bike or talking on the phone.

Declarative memory can be further divided into episodic and semantic memory, which refers to whether memory involves connections to times or places.

Episodic memory refers to autobiographical information that includes a temporal or spatial context. For example, you can remember what happened on a particular vacation.

refers to autobiographical information that includes a temporal or spatial context. For example, you can remember what happened on a particular vacation. Semantic memory refers to factual information unconnected to events that happened in your past. For example, you may remember owning a bicycle but not remember where you bought it or where you rode it.

Brain areas involved in memory

Multiple brain areas are involved in anterograde amnesia. Research tells us that the hippocampus and nearby subcortical regions are likely to be involved. The medial temporal lobe (MTL), basal forebrain, and fornix have all been considered potential parts of the brain that may play a role in anterograde amnesia.

The MTL system consists of the hippocampal, perirhinal, entorhinal, and parahippocampal areas of the brain and is important for factual recall (declarative memory). The MTL is not involved in non-declarative memory.

Examples of anterograde amnesia

In the most famous case study of a person with anterograde amnesia, the patient named H.M. was shown to be able to learn how to complete a maze even though he had no memory of completing the maze before. HM. suffered from anterograde amnesia following surgery to cure his epilepsy.

Another famous case study of anterograde amnesia is that of Clive Wearing, who contracted the herpes simplex virus and associated complications in his brain. Following this event, Wearing developed significant retrograde and anterograde amnesia. However, he retained his ability to play the piano and direct a choir.

Symptoms of anterograde amnesia

Because people with anterograde amnesia cannot create new memories, someone with this form of amnesia forgets things like:

A person you just met

What they ate last

New phone numbers

Recent life changes

Things you’ve learned recently

A person with symptoms of anterograde amnesia may remember how to make a phone call, but does not remember what they did this morning. This is because declarative and non-declarative memories are believed to be stored in different areas of the brain. In addition, these individuals have often lost the episodic part of declarative memory but not the semantic part.

Anterograde amnesia vs. retrograde amnesia

Anterograde amnesia differs from retrograde amnesia in the timing at which memories are lost. People with retrograde amnesia cannot remember things that happened before the event that caused their amnesia. But they can form new memories after the event.

Conversely, people with anterograde amnesia can often remember everything up to that event—but can’t remember things that happened after that date. It’s also possible for a person to have both types of amnesia, known as severe global amnesia.

How long can anterograde amnesia last? While some cases of anterograde amnesia can be temporary, this condition is usually permanent and can get worse over time. It’s important to seek treatment if you have unexplained memory loss. Your doctor can determine the underlying cause of your memory loss and suggest appropriate treatments.

Causes of anterograde amnesia

There are several possible causes of anterograde amnesia, all of which involve some type of trauma or stress to the brain. Factors that may increase the risk of anterograde amnesia include:

Drug Use: Short-term anterograde amnesia can result from use of certain medications.

: Short-term anterograde amnesia can be caused by taking certain medications. Benzodiazepines: This type of medication has been linked to anterograde amnesia, along with the use of non-benzodiazepine sedatives such as zolpidem (Ambien).

: This type of medication has been associated with anterograde amnesia along with the use of non-benzodiazepine sedatives such as zolpidem (Ambien). Traumatic Brain Injury: Damage to or around the hippocampus has been associated with anterograde amnesia.

: Damage to or around the hippocampus has been associated with anterograde amnesia. Brain Inflammation Brain inflammation such as encephalitis has been associated with signs of anterograde amnesia.

: Inflammation of the brain such as encephalitis has been associated with signs of anterograde amnesia. Brain Surgery: In patients who have had parts of the brain removed, such as B. the MTL, impairments were shown in connection with anterograde amnesia.

: In patients who have had parts of the brain removed, e.g. B. the MTL, impairments were shown in connection with anterograde amnesia. Stroke: Stroke has been associated with anterograde amnesia.

: Stroke has been associated with anterograde amnesia. Alcohol Blackout: A person who consumes a large amount of alcohol in a short period of time may experience memory loss for the time they were drinking. However, after the episode, her memory function would return to normal.

: A person who consumes a large amount of alcohol in a short period of time may experience memory loss for the time they were drinking. However, after the episode, her memory function would return to normal. Chronic alcoholism: Heavy drinking over time can lead to thiamine (B1) deficiency, which leads to Korsakoff syndrome, which causes significant problems in anterograde episodic memory.

: Heavy drinking over time can lead to thiamine (B1) deficiency, leading to Korsakoff syndrome, which causes significant problems in anterograde episodic memory. Concussion/Sports Injury: Concussion and sports injuries to the head have been associated with anterograde amnesia.

: Concussion and sports injuries to the head have been associated with anterograde amnesia. Electroconvulsive Therapy: ECT is an effective treatment for depression. Anterograde amnesia is an observed side effect, although research suggests this effect may be transient or short-term.

Diagnosis of anterograde amnesia

Diagnosing anterograde amnesia may involve the use of brain scan technologies such as magnetic resonance imaging (MRI) and CT scan. In addition, the doctor will ask questions to better understand the memory loss, such as:

Whether long-term or short-term memory is affected

When the memory problem started

What could have caused the anterograde amnesia if you know

If there is a family history of similar problems

Any substance use or history of seizures

Related problems, such as confusion, language problems, or personality changes

Treatment of anterograde amnesia

Although there is no cure for anterograde amnesia, some recovery and rehabilitation may be possible — even with permanent damage. Treatments for anterograde amnesia are primarily aimed at treating the condition. The following strategies are often used:

Reminders like alarms

Magazines, notes or diaries

family support

occupational therapy

There is no FDA-approved drug treatment for amnesia. However, vitamin B1 (thiamine) supplements can be used in cases where there is a vitamin deficiency. Technical aids can also be used to provide assistance, often in the form of daily planners and reminder apps.

Dealing with anterograde amnesia

Some self-help strategies can help people with anterograde amnesia. This can include establishing defined daily routines and finding ways to mark the passage of time.

Outline daily tasks, including things like grocery shopping, money management, meal prep, and appointments. This list should be visible and accessible at all times. Break down daily tasks into smaller steps and check progress.

People with amnesia may lose track of time and spend hours on the same task. One way to deal with this is to create a laminated chart of what needs to be done for each task and place it in a prominent place.

Treating anterograde amnesia requires the use of memories. Technology can be useful, but handwritten checklists and other tools can also help.

A word from Verywell

If you or someone you know is living with anterograde amnesia, it can be difficult to know how to manage it or help your loved one. This type of impairment can affect day-to-day functioning, especially if it is severe.

Support from family and friends is crucial and should be part of any treatment plan whenever possible. If you’re struggling to cope with anterograde amnesia, other treatment options with new strategies to manage your disability may be warranted.

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1

: Affecting memories for a period immediately after a triggering event (such as alcohol intoxication, traumatic brain injury, electroconvulsive therapy, or severe emotional stress) and particularly from the time of onset to the present

anterograde memory loss

He suffered from anterograde amnesia. He drew from his past and registered the present, but his brain could not consolidate and hold onto a new experience.

Muhammad has been to his school canteen hundreds of times. It is a large room and there are nine freestanding pillars supporting the roof. One day, to illustrate the nature of forgetfulness, Muhammad’s teacher asks him how many pillars there are in the cafeteria. Muhammad has difficulty answering the question, but eventually replies that he believes there are six pillars. What storage concept does this example illustrate?