Introduction to Psychology, 7th Edition, James W. Kalat Chapter 7: Memory Chapter 7 Memory

Introduction to Psychology, 7th Edition, James W. KalatChapter 7: Memory

Chapter 7

Memory


Memory

Memory is a general term for the storage, retention and recall of events, information and procedures.

The quality of an individual’s memory may vary based upon the nature of the information being retained and recalled, the level of interest in it, and its significance to that individual.


Module 7.1

Varieties of Memory


Ebbinghaus’s Pioneering Studies of Memory

Hermann Ebbinghaus studied his own ability to memorize new material He invented over 2300 nonsense syllables and put them

into random lists. Over 6 years he memorized thousands of lists of

nonsense syllables. Generally he found that delay between memorization

and recall resulted in the forgetting of a large portion of the material.


Figure 7.1 Hermann Ebbinghaus pioneered the scientific study of memory by observing his own capacity for memorizing lists of nonsense syllables.



Role of interference Part of the difficulty for Ebbinghaus may have been the

fact that he memorized so many lists of nonsense syllables.

If an individual learns several sets of related materials, the retention of the old material makes it harder to retain new material, and the learning of the new materials makes it harder to retain the old.

This phenomenon is known as interference.



Role of interference When retaining old material makes it hard to retain new

material, this is called proactive interference. When learning new material makes it hard to retain old

material, this is called retroactive interference. The problem for Ebbinghaus was that he had memorized

so many lists of nonsense syllabus that he experienced a strong effect from proactive interference.


Concept Check

You answer the telephone at your new receptionist job with the name of the your former employer’s firm. What kind of interference caused this embarrassing slip-up?

Proactive interference



Meaningfulness Another feature of the pioneering work of Ebbinghaus is

that he memorized nonsense syllables. It is clear from studies of memory that meaningful

materials are easier to remember. It is also true that distinctive or unusual information is

easier to retain. The tendency of people to remember unusual items

better than more common items is called the von Restorff effect.



Dependence of memory on the method of testing It is possible that since Ebbinghaus required himself to

repeat the syllables in correct order after memorizing them, he underestimated his actual retention of the information.

How well one appears to remember something depends in part on how one is tested after learning.



Dependence of memory on the method of testing Recall (or free recall) is the simplest method for the

tester but the most difficult for the person being tested. To recall something is to produce it, as is done on essay and short-answer tests.

Cued recall gives the person being tested significant hints about the correct answer. A fill-in-the-blank test uses this method.


Table 7.1 The difference between recall and cued recall



Dependence of memory on the method of testing Recognition is the method that requires the person being

tested to identify the correct item from a list of several choices. Multiple-choice tests use the recognition method.

The savings, or relearning method compares the rate at which someone relearns material as opposed to learning something new. The amount of time saved between the original learning and the relearning is a measure of memory.



We are indebted to Ebbinghaus for initiating the scientific study of memory.

We have also learned important facts about the nature of memory from his difficulties with interference.


Concept Check

The bonus question on your Introductory Psychology test asks you to name the stages of the human sleep cycle.

Recall


Concept Check

You are on a game show and the question that you must answer is “_________ is the city that is home to the Eiffel Tower, the Louvre, and the Cathedral of Notre Dame.”

Cued recall


Concept Check

You answer more questions on the subject of molecular biology correctly on the comprehensive semester final than you did on the chapter test two months earlier.

Relearning or Savings


Concept Check

While at a hardware store, you are looking at several shades of light green paint in hopes of repainting the walls of your home in that exact shade.

Recognition memory


The Information-Processing View of Memory

The information-processing model of memory draws an analogy between a computer and the workings of memory in the human brain. According to this view, information enters the system, is

processed and coded in various ways, and is then stored.


Figure 7.4 The information-processing model of memory resembles a computer’s memory system, including temporary and permanent memory.



The computer has a “buffer” – a temporary storage place for letters that you type faster than it can display them.

This is akin to our sensory memory store



The computer has RAM, or random-access memory, for temporary storage of information that has not yet been written to the hard drive. This information is still vulnerable to damage or loss.

This is analogous to our short-term, or working memory.



The computer has a hard drive, in which information that you are writing or entering can be permanently stored.

This is like our long-term memory.



The sensory store Although it is probably more accurately described as a

combination of memory and perception, the sensory store is considered to be the first stage of memory processing.

It is a very brief (less than a second) stage that registers everything that is perceived in the moment that we call “now.”


Figure 7.5 George Sperling (1960) flashed arrays like this on a screen for 50 milliseconds. After the display went off, a signal told the viewer which row to recite.



Short-term and long-term memory Temporary storage of information that someone has just

encountered is short-term memory. Long-term memory is a relatively permanent storage of

mostly meaningful information. Reminders or hints that help us to retrieve information

from long-term memory are referred to as retrieval cues.



Short-term memory If a friend asks you what he or she just said, and you

were paying attention, you could probably repeat their words or something close to them.

This is because you are being asked to recall something from short-term memory.

If you were not paying attention, you would not recall it at all. Attention is the process that moves information from the sensory store to short-term memory.


Table 7.3 After about 1 second, you can no longer recall information from the sensory store. Short-term memories can be recalled up to about 20 seconds without rehearsal—much longer if you continually rehearse them. Long-term memories decline somewhat, especially at first, but you may be able to retrieve them for a lifetime. Your address from years ago is probably in your long-term memory and will continue to be for the rest of your life.



Long-term memory If your psychology instructor asks you to name the

function of the thalamus, your first reaction might be to panic because you have no idea.

The instructor says, “It has something to do with sensory information, right?”



Long-term memory Then it begins to come back to you – the thalamus is a

relay and integration station for sensory information on its way to the cerebral cortex.

The instructor gave you a hint that functioned as an effective retrieval cue. These cues can be generated internally or be suggested by others.



Capacities of short and long-term memory Most normal adults can immediately repeat a list of

about seven bits or pieces of information, with expected variations in range from five to nine items.

This “magic range” of 7 +/- 2 bits is a well-replicated finding regarding the capacity of short-term memory.

It can be expanded through techniques such as chunking into larger, meaningful units.


Figure 7.6 We overcome the limits of short-term memory through chunking. You probably could not remember the 26-digit number in (a), but by breaking it up into a series of chunks, you can remember it and dial the number correctly.



Capacities of short and long-term memory The capacity of long-term memory cannot easily be

measured. Unlike a computer, we are not dealing with a physical

limit of size. Humans are constantly dumping or removing some of

their stored information through disuse.



Decay of short and long-term memory Information that has been stored in long-term memory

may be vulnerable to the aforementioned effects of interference, but it generally does not decay due to the effects of time alone.

Information being held in short-term memory is vulnerable immediately to the effects of the passage of time.

Forgetting tends to begin in seconds unless rehearsal is permitted.


Figure 7.9 In a study by Peterson and Peterson (1959), people remembered a set of letters well after a short delay, but their memory faded greatly over 20 seconds if they were prevented from rehearsing during that time.



Capacities of short and long-term memory How long one is able to hold information in short-term

memory has little relationship to how well it will be stored in long-term memory.

If the information being held in short-term memory is meaningful, it will be transferred easily to long-term memory and be less subject to decay.

Up until recently, cognitive psychologists referred to this transfer process as consolidation, the formation of a long-term memory.



Capacities of short and long-term memory It is now thought that how easily information is

consolidated depends on its meaningfulness to the individual. This idea implies that perhaps the division between the short and long-term memory stages is at least in part an artificial one.

If the information is meaningful, the groundwork for storing that information has already been done.



Working memory Working memory is a revised concept of the

intermediate stage between our first encounter with new information and its eventual storage.

Working memory is a system for processing or working with current information.

Working memory is conceptualized as having three major components.



Working memory’s 3 components: A phonological loop that stores and rehearses

information, similar to the 7 +/- 2 idea from the traditional concept of short-term memory.

A visuospatial sketchpad that stores and manipulates visual and spatial information.

A central executive that governs shifts of attention. Good working memory is able to handle shifts between two or more tasks or multiple aspects of complex tasks.



Other memory distinctions Declarative memory is the ability to state a fact. Procedural memory is the memory of how to do

something. Long-term declarative memory is classified as either

semantic (dealing with principles of knowledge) or episodic (containing events and details of life history.)

Your memory of a recent piano lesson is declarative and episodic; your memory of how to read music is semantic; your memory of how to play the piano is procedural.



Other memory distinctions A normal type of forgetting is source amnesia. This involves a combination of episodic and semantic

memory. We remember a statement or knowledge related (semantic) fact but we forget the context in which we learned it.



Other memory distinctions The context in which one learns information is episodic. It can be inferred from the occurrence of this

phenomenon that episodic memory is more fragile than semantic knowledge.


Varieties of Memory

Although there is still much disagreement about the nature of memory, there is general agreement that memory is not a single store into which we dump the sum of our knowledge and experiences.


Varieties of Memory

Memory is a complex combination of many processes, and its properties depend on a number of factors The type of material memorized The individual’s experience with similar materials The method of testing The length of time since the material was encountered


Module 7.2

Long Term Memory Storage


Memory Improvement

To improve memory, one must improve the strategies used to originally store the material.


The Influence of Emotional Arousal

It is well understood that the greater the emotional arousal associated with an event, the greater the likelihood that the event will be remembered. Although the event itself may be remembered, the

emotion associated with the event does not guarantee the formation of an accurate memory for the details of the event.


The Influence of Emotional Arousal

During stressful or emotional events, the sympathetic nervous system works to boost production of the hormones cortisol and adrenaline.

This is usually accompanied by increased stimulation of the amygdala.

The net effect of these processes is to enhance memory storage of information associated with emotional or stressful events.


Concept Check

A Vietnam War Veteran who was involved in several very intense and violent campaigns has been medically monitored for years. He has lower than normal levels of cortisol. How would this affect his memory?

He should report frequent memory lapses.


Meaningful Storage and Levels of Processing

The levels-of-processing principle The levels-of-processing principle states that the ease

with which we can retrieve a memory depends on the number and types of associations that we form with that memory

The more ways in which you think about the material, the deeper your processing will be and the more easily you will remember the material later.



The levels-of-processing principle Ways to think about the material would include asking

questions such as: Can I think of similar concepts in another subject

area? How do these apply to me? What experiences do I have that are related to this

information?



The levels-of-processing principle To improve your level-of-processing:

Think about each individual item in a set that you are trying to learn.

See if you can determine whether or not relationships exist among the items.



The levels-of-processing principle The levels of processing are:

Superficial processing – simply repeating the material that you are trying to memorize.

Deeper processing – think about each item or parts of the material individually.

Still deeper processing – note the associations between the items or parts of the material.


Concept Check

Who do you think tends to get better grades in a course, students who read the book quickly or those who read the book slowly?

The slow pokes


Concept Check

How would level-of-processing be useful to aspiring actors?

It would help them memorize their lines more effectively.


Timing of Study Sessions

The serial-order effect The serial-order effect states that we tend to remember

the beginning and end of a list better than the middle. The primacy effect is the tendency to remember the

beginning. It is partly due to the lack of proactive interference

while you rehearse the first few items. The recency effect is the tendency to remember the

end. The last few items are not subject to as much

retroactive interference.



Because of these effects, the best strategy for anyone who needs to learn a lot of material is to space out the study sessions Study the material Wait for awhile Return to the material and test yourself on it



The SPAR method If you want to remember something for the long-term,

study and review it under varying conditions with substantial intervals between sessions

One systematic way to accomplish this is to use the SPAR method.



The SPAR method Survey – get an overview of the material. Process meaningfully – read the material carefully and

think about how it relates to your other knowledge and experiences.

Ask questions – use the review questions included with the material, or create your own and answer them.

Review – wait a day or so, and retest yourself.


Concept Check

In order to ace your comprehensive Introductory Psychology final exam, should you immediately review this chapter, or should you schedule some review of the first two or three chapters?

Start reviewing the earlier material


Use of Special Coding Strategies

Retrieval Cues Retrieval cues are bits of associated information that

help you to regain complex memories for later use. Many factors associated with learning can act as retrieval cues.

The encoding specificity principle states that the associations formed at the time of learning are typically the most effective retrieval cues.

State-dependent memory is our tendency to remember something better if your physical condition is the same at the time of recall as it was at the time of learning.


Figure 7.11 According to the principle of encoding specificity, the way we code a word during original learning determines which cues will remind us of that word later. For example, when you hear the word queen, you may think of that word in any of several ways. If you think of queen bee, then the cue playing card will not remind you of it later. If you think of the queen of England, then chess piece will not be a good reminder.


Table 7.5a


Table 7.5b


Use of Special Coding Strategies

Mnemonic devices A mnemonic device is any memory aid that is based on

encoding each item in a special way. There are many types of mnemonic devices.

The method of loci involves memorizing a series of places. Using a vivid image, you associate each of these locations with something you want to remember.

The peg method involves memorizing a list of objects (“pegs”) and forming mental images to link the information that you wish to memorize using these pegs.


Figure 7.12 A simple mnemonic device is to think of a short story or image that will remind you of what you need to remember. Here you might think of images to help remember functions of different brain areas.


Figure 7.14 The method of loci is one of the oldest mnemonic devices. First, learn a list of places, such as “my desk, the door of my room, the corridor, . . .” Then link each of these places to the items on a list of words or names, such as a list of the names of Nobel Peace Prize winners.


Improving Our Memory

We refer to our memories as “stored” and “retrieved” as if they were items on a shelf in a warehouse. But this analogy is only partially useful.

The more you know about a topic, the more interested you are in it, the easier it is to establish and retain new information related to the topic.


“Normal” Forgetting

There are many plausible reasons to account for the forgetting of information Interference Decay – the memory is subject to the combined effects

of time and interference Loss of retrieval cues Source amnesia


Module 7.3

Retrieval of Memories


Reconstructing Past Events

When you try to remember an event, you usually start with details you remember clearly, and fill in the gaps.

This is the process of reconstruction. During an event, we construct a memory. When we try to retrieve the memory, we reconstruct an account based partly on surviving memories and partly on expectations of what must have happened.



Your memory for activities that are routine – your breakfast, lunch or dinner for example – from the past week can be reconstructed with little effort. But these will fade rapidly unless something unusual happened.



If your family all got sick after one meal, you will probably remember that meal in better detail for much longer than is usual.

If you met a new love interest when you were out to dinner with friends, this event will also be more memorable and easily reconstructed.

However, you may fill in missing details with typical activities associated in your memory with routine meals at home or dining out.



We will add words to lists that we’ve heard or read depending on what content we believe would have been on the list, based on its apparent theme.

The less certain of our memories that we are, the more we will rely on our expectations.



Hindsight bias Hindsight bias is the tendency to mold our recollection of

the past to how events later turned out. We say “I knew that was going to happen!” after the

event has occurred. Our memories are tailored as we reconstruct the

event to fit that outcome.


Figure 7.17a Mean estimates of the likelihood of four outcomes varied depending on what each group was told about the “actual” outcome. Those who thought the British had won said that under the circumstances the British had a very high probability of victory. Those who thought the Gurkas had won said that was the most likely outcome under the circumstances, and so forth. (Based on data of Fischhoff, 1975)


Figure 7.17b Mean estimates of the likelihood of four outcomes varied depending on what each group was told about the “actual” outcome. Those who thought the British had won said that under the circumstances the British had a very high probability of victory. Those who thought the Gurkas had won said that was the most likely outcome under the circumstances, and so forth. (Based on data of Fischhoff, 1975)


Figure 7.17c Mean estimates of the likelihood of four outcomes varied depending on what each group was told about the “actual” outcome. Those who thought the British had won said that under the circumstances the British had a very high probability of victory. Those who thought the Gurkas had won said that was the most likely outcome under the circumstances, and so forth. (Based on data of Fischhoff, 1975)


Figure 7.17d Mean estimates of the likelihood of four outcomes varied depending on what each group was told about the “actual” outcome. Those who thought the British had won said that under the circumstances the British had a very high probability of victory. Those who thought the Gurkas had won said that was the most likely outcome under the circumstances, and so forth. (Based on data of Fischhoff, 1975)



The “false” or “recovered” memory controversy Reports of long-lost memories, prompted by clinical

techniques, are known as recovered memories. Often these are memories of abuse that took place in early childhood.

There have been examples of accurate and inaccurate memories constructed through clinical techniques.

Psychological researchers want to know if it is likely that people will forget abusive or traumatic experiences.



Memory for traumatic events Sigmund Freud believed that it was possible to repress a

painful memory, motivation or emotion, to move it from the conscious to the unconscious mind.

This idea is not well supported in research on memory and forgetting.



Memory for traumatic events Research indicates that it is possible to forget a

traumatic event, but whether this happens depends on a number of factors – age at the time of the event, reaction of family, and type of event.

Most people do not forget traumatic events if they happen later than age 3.



Memory for traumatic events Whether this happens because of repression or normal

forgetting is unclear. People forget many pleasant and joyful events from early childhood as well.

Repression of traumatic events does not fit well with our understanding of the biological process of storing memory.

Emotional stimulation releases cortisol. The net effect is to improve the storage of memory.



Suggestion and false memory A false memory is a report that an individual believes to

be a memory but that does not correspond to actual events.

Various studies have shown that it is possible by suggestion to implant memories for events that did not occur.

About a quarter of subjects in several studies were convinced that they had been lost as children after a researcher suggested it to them.



Suggestion and false memory Plausible events were more likely to be remembered,

and the memories were somewhat vague, but these results were achieved after a single, brief suggestion.

Similarly, memory for details after watching a videotaped event can be altered or distorted by the use of leading questions.



Children as eyewitnesses Research with children can be ethically difficult because

of their vulnerability. We know that children forget rapidly and sometimes

confuse fantasy and reality. Sometimes children witness crimes or other events about which we need information.

How do we work with children to tap their memories accurately? Can we do this?



Children as eyewitnesses Under proper conditions, children as young as three are

able to make accurate reports of events that they have witnessed.

Young children can answer specific questions accurately.

If there is a delay between the event and the questioning, a child is more likely to give incorrect information.

If the question is not understandable, the child may give incorrect information.



Children as eyewitnesses Repetition of the question in the same interview session

may yield two different answers. Repetition of the question between spaced interview

sessions may help the child remember better, which is important in court testimony.

Dolls and props may seem like helpful tools, but actually do not increase the accuracy of a child’s recall or testimony.



Children as eyewitnesses The most effective strategies in interviewing young

children are: Use of simple questions Maintenance of a non-threatening atmosphere during

the interview Avoidance of suggestions or pressure Schedule the interview as soon as is reasonable after

the event


True, False, Maybe

Memories may or may not be reliable. There is much evidence of forgetting and distortion. We

use adaptive strategies for “filling in the gaps” – reason and logic.

It is prudent to always consider the possibility that a seemingly clear memory is distorted or false.


Module 7.4

Amnesia


Amnesia After Brain Damage

Amnesia is a severe loss or deterioration of memory. We can learn a lot about the different forms of memory by

studying these cases.



“H.M.” In 1953, “H.M.” had his hippocampus and surrounding

areas of the temporal lobes removed to control his intractable seizures.

Although his seizures did decrease dramatically, he experienced such dramatic memory impairment that such a surgery would never be attempted again.


Figure 7.19 (a) The hippocampus is a large subcortical structure of the brain



“H.M.” He experienced massive anterograde amnesia. He

was unable to store any new memories. (It was 1953 for the rest of his life.)

He had moderate retrograde amnesia. He could not remember many events that occurred between 1 and 3 years before his surgery.

He did retain normal short-term memory functions. His procedural memory was retained intact.


Figure 7.20 Brain damage induces retrograde amnesia (loss of old memories) and anterograde amnesia (difficulty storing new memories.)



“H.M.” What has been learned about the hippocampus from

H.M.’s tragic story? All other things being equal, the more difficult a

memory task is, the more it depends on the proper functioning of the hippocampus.

The hippocampus is important for remembering details.



Frontal-lobe damage The frontal lobes receive a great deal of input from the

hippocampus. Damage to the frontal lobes causes some problems that are similar to hippocampal damage, and some unique problems as well.

Frontal lobe damage can occur as a result of stroke, head trauma, or Korsakoff’s syndrome, a dementia that results from a deficiency of vitamin B1, brought on by chronic alcoholism.



Frontal-lobe damage The deficiency leads to loss and shrinkage of neurons in

many parts of the brain, especially the thalamus and prefrontal cortex.

Multiple impairments of memory can result from this deterioration.



Frontal-lobe damage Typical symptoms of Korsakoff’s syndrome include –

Apathy Confusion Retrograde amnesia – usually dating back to about

15 years before the onset of the syndrome Anterograde amnesia Confabulation – wild guessing mixed in with correct

information, generated in an effort to hide gaps in memory.



Implicit memory in amnesiac patients Recall these two divisions of long-term memory:

Explicit memory involves the recall of knowledge and events in which a person deliberately retrieves the answer and recognizes it as a correct one.

Your instructor asks you to name two psychologists associated with the principles of operant conditioning.



Implicit memory in amnesiac patients Implicit memory does not require recognition. The recall

of activities stored in implicit memory seems effortless and unconscious.

You drive your car to school everyday but don’t remember any details of the activities associated with driving.



Implicit memory in amnesiac patients Amnesiac patients such as H.M. show normal ability to

use and store new implicit memory, but have impaired functioning of the factual memory activities of explicit memory.



Implicit memory in amnesiac patients NOR____ DET____ COR____ FRO____ Complete the words listed above.



Implicit memory in amnesiac patients If you wrote any of the following – normal, detail, correct

or cortex, frontal, there is a good chance that you were recalling words that appeared in the slides that preceded the task. It will be easy for you to remember this now that you know what happened.

Amnesiac patients will perform similarly on this task – called “priming” – they will complete the words in a similar manner, but they will never remember having read them previously.



Implicit memory in amnesic patients It is not uncommon for such a patient to learn a video

game or other procedural task perfectly. However, the patient will never remember the event of being taught the game, or any individual session of playing it, even if that patient becomes highly skilled at the actual playing!


Concept Check

You have learned to play the guitar. What type of memory is involved in playing a song for your friends?

Implicit memory


Concept Check

You play guitar at a party for your friends. Later you remember the good time you had playing for them. What type of memory is involved in remembering this?

Explicit memory


Concept Check

Which of the following is an example of implicit memory? a. There is a soap opera on TV at home. You don’t get to

watch it often, so you can never tell your friends the names of the characters. Two days later you are watching a late night TV program and you recognize one of the leading men as a guest.

b. You are sitting behind a couple at the movies who are having an animated discussion about skydiving. You are not paying attention to the content of their discussion. Later you spontaneously comment to your friends about how much fun it would be to learn to skydive.

“ b” is implicit memory


Concept Check

What kinds of memory are most impaired in frontal lobe dementia patients and patients like H.M.? What kinds are least impaired?

Declarative or explicit memories are most impaired.

Procedural or implicit memories are least impaired.


Infant Amnesia

Few people can remember events earlier than age 5 or 6. Though children younger than this can describe earlier events in their own lives, these memories tend to fade.

The scarcity of early declarative memory is called infant amnesia or childhood amnesia. Why does this happen?


Infant Amnesia

Freud believed that this was a result of repression due to the emotional traumas of infancy. He offered no evidence for this theory.

Some cognitive psychologists believe that this is because early memories are nonverbal and later memories are verbal.

A biological explanation is that the hippocampus is not fully developed and doesn’t store memories as completely.


Infant Amnesia

Another cognitive explanation is that lasting memories require a sense of self, and this typically doesn’t develop fully until between 3 and 4 years of age.

The theory of encoding specificity suggests that our retrieval cues in later life may not be adequate to recall early memories.

We are still trying to understand why these memories are not accessible.


Amnesia of Old Age

Some older people suffer from Alzheimer’s and other dementias that impair attention and memory.

Up until recently, scientists have typically overstated the vulnerability of healthy older people to memory loss.


Amnesia of Old Age

Most healthy people show little decline of memory in old age Older adults show mild deficits on simple memory tasks. Older adults show greater deficits on more complex

tasks. The attentional aspects of their working memory appear

to be weaker – older adults have more difficulty handling two tasks at once.


Amnesia of Old Age

People would like to know how to increase the chance of having good memory function later in life: A healthy lifestyle with regular exercise, good diet and

limited use of alcohol. An intellectually stimulating life may be related to good

memory function as well.


Why do we forget?

Catastrophic loss of memory can only result from brain damage or disease.

“Normal” forgetting is a product of mechanisms that are usually adaptive.

It is probably true that remembering everything that happened would be overwhelming and debilitating for human beings.

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Introduction to Psychology, 7th Edition, James W. Kalat Chapter 7: Memory Chapter 7 Memory