Module 6.1 Remembering
Module 6.2 Forgetting
Module 6.3 The Biology of Memory
Memory is a fascinating process that has intrigued psychologists for decades. Over the past century, psychologists have realized that memory is an extremely complex process, which sometimes acts in mysterious ways. For example, we may be better able to remember the circumstances of our first kiss than what we had for dinner last night.
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Module 6.1
Remembering
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Encoding
Storage
Retrieval
© Cengage Learning
Three key processes of memory are analogous to the workings of the modern computer.
The first process, encoding, involves bringing information into memory. Like a scanner or copier, we have to encode stimuli into a form our brain understands and can process.
The second question is, how is that information stored or maintained in memory?
The third question is, how is the stored information retrieved or pulled back out of memory? Like a computer monitor retrieving information to display, we too call up information and “display” it in various forms (e.g., talking, thinking, moving).
Although technology serves as a nice analogy, the inner workings of our memory are far more complex.
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Acoustic
Visual
Semantic
© Cengage Learning
Encoding
Getting information into memory
We will begin with encoding, which involves forming a memory code from some stimulus.
Let’s start with encoding . There are three basic ways information can be encoded:
— Acoustically (by sound, as in remembering a melody)
— Visually (by forming a visual image, as in remembering the arrangement of your living room furniture)
— Semantically (by focusing on the meaning of the information, such as when you remember a new vocabulary word by using it in a sentence)
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© Timothy Boomer/Shutterstock.com
Putting things into memory would be a rather useless process unless those data can remain there, hopefully unchanged, over time. Memory storage is where memories “hang out” until they are needed again in the future, at which time retrieval takes place.
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Retrieval Cues
Word Definition
Favoritism shown or patronage granted by persons
in high office to relatives or close friends
Retrieval Cue 1: Begins with “N”
Retrieval Cue 2: Ends in –ism
Retrieval Cue 3: First syllables rhymes with pep
We’ll touch upon the contents of stored memories in a moment. For now, let’s recognize that the journey into long-term memory is complex and takes considerable effort and that storage of long-term memories is only beneficial if you’re able to retrieve that information at a later time.
When you are not be able to retrieve information that feels as if it’s just out of your reach, you are experiencing the tip-of-the-tongue phenomenon. Though this shows a failure in retrieval, researchers have shown that retrieval can occur more frequently when retrieval cues are present.
Retrieval cues are stimuli that help gain access to memories.
Context cues are types of retrieval cues that can aid our retrieval of memories. Working with context cues involves putting yourself in the context in which a memory occurred. For example, you may forget what you were looking for when going from your bedroom to the kitchen, but once you return to the bedroom you might remember “Oh yeah, I wanted a glass of water”. This is because the context cues in your bedroom help you retrieve the memory
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Sensory
Memory
Long-Term Memory
Short-Term Memory
© Cengage Learning
Now that we understand more about the processes of encoding and retrieval, we turn now to the three stages of memory.
Memory researchers identify three distinct, time-based memory storage systems: sensory memory, short-term memory, and long-term memory.
It is important to realize that, like the computer example of memory, information processing is a metaphor – the three storage systems do not refer to tiny “lockers” in the brain where information actually sits.
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© Yakobchuk Vasyl/Shutterstock.com
Sensory memory is a temporary storage buffer that preserves sensory impressions for perhaps a fraction of a second to perhaps a few seconds.
Information in sensory memory is held in a “sensory register. ” For visual information, this is called iconic memory (eidetic imagery or photographic memory). For auditory information, the buffer is called echoic memory (an “echo” of a sound).
What’s great about sensory memory is that it allows us to experience a visual pattern, sound, or touch even after the event has come and gone. In doing this, sensory memory gives us additional time to recognize things and bring them into memory.
But the extra time isn’t much –for vision and audition, sensory memories only last about .25 seconds. You can see this characteristic of sensory memory, called an afterimage, when a flashlight or sparkler is moved about quickly, creating what appears to be a continuous figure. A sound echo is another form of sensory memory.
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© Kelly Marken/Shutterstock.com
Short-term memory (STM) allows us to hold information in mind for upwards of 30 seconds or so. STM, which is also called working memory, has a limited capacity—it can only store so much information at any one time.
This was first discovered by George Miller in the 50s, when he found that most participants could only remember 7 plus or minus 2 digits. When we need to memorize more than these amounts, the information already stored in our short-term memory is displaced. But alas, we have ways of overcoming the 7 plus or minus 2 rule.
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FBINBCCIAIBM
Chunking
In order for this to work, the “chunks” must be personally meaningful and easily recognized!
FBI NBC CIA IBM
Rather than viewing information broken into bits, we can store multiple bits as chunks, a processing known as chunking. For example, take the letters FBINBCCIAIBM.
Few could recall these from short-term memory, but by using chunking, we can put these letters into meaningful, easy-to-memorize units, such as FBI-CIA-NBC-IBM. In this demonstration, we went from working with 12 down to 4 pieces to remember.
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© Cengage Learning
The final stop for memory storage is in our long-term memory. Long-term memory is an unlimited capacity storage that can hold information over long periods of time.
Consolidation occurs when unstable, new memories are converted to stable, long-term memories.
One question about the nature of long-term memory is, after it’s passed on from short-term memory, can the memories stay forever or do they fade out with time?
Fortunately, memories can endure indefinitely, especially when we make the effort to strengthen new memories. Think of long-term storage as a barrel of infinite size, full of memories represented by marbles. We can make memories more durable through repeated practice, a process we can liken to shining the marbles every now and then (such as continuing to practice speaking a foreign language to keep your memory of the language sharp).
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Fire Engine
Red
Fire
Truck
House
Ambulance
Orange
Green
Yellow
Violets
Flowers
Roses
Sunrises
Sunsets
Clouds
Cherries
Apples
Pears
Bus
Car
Street
Vehicle
One way we organize information is through semantic networks. Semantic networks consist of nodes representing concepts, joined together by pathways that link related concepts. For example, the phrase “fire truck” may be organized in a network of similarly related words, such as truck, fire, and red. In this network, words closer to one another are more strongly related. The inventor of the World Wide Web, Tim Berners-Lee, used the semantic network as a representation of how the brain does memory, as a model for developing the computer architecture that become the Web.
When one “node” in the network is activated, others that are nearby also light up. This causes ones near them to turn on, and so on, in a ripple effect called spreading activation.
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This video shows how psychologists use high-tech brain imaging procedures and computer simulations to better understand learning and memory.
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Memory
Declarative Memory
(Factual Information)
Procedural Memory
(Actions, Perceptual Motor
Skills, Conditioned Responses,
Emotional Memories)
Example: Riding a bike
Handle Bars
Pedals
Spokes
© Cengage Learning
Some memory theorists propose different systems of memory. The most basic distinction is made between declarative and nondeclarative memory.
Declarative memory handles factual information and information that requires a deliberate effort to recall, whereas nondeclarative memory (also called procedural memory or implicit memory) houses memory for skilled actions (memory of “how”), conditioned responses, and emotional experiences.
If you know that a bike has two wheels, pedals, handlebars, etc., you are using declarative memory. However, if you know how to ride a bike, you are employing nondeclarative memory.
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© Cengage Learning
We may divide declarative memory into episodic and semantic memory.
Episodic memory is made up of chronological, or temporally dated, recollections of personal experiences. Episodic memory includes all memories in which a “time stamp” is made. That is, you remember an event associated with some information.
Semantic memory contains general knowledge that is not tied to the time when it was learned. For example, that January 1st marks the new year, that dogs have four legs, etc., are examples of information related to semantic memory. An appropriate analogy is to think of both as books. Episodic memory is an autobiography whereas semantic memory is an encyclopedia.
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Prospective
Memory
Retrospective
Memory
The Present
Past
Future
© Cengage Learning
Researchers have not only broken down memories into declarative and procedural memory, but also into two different types of long-term memory: prospective and retrospective.
Prospective memory involves remembering to perform actions in the future. For example, remembering to walk the dog or to take your medication involves prospective memory.
Retrospective memory involves remembering events from the past or previously learned information. For example, in retrospective memory you may try to remember who won the Super Bowl last year or what last week’s lecture covered. Research is under way to determine whether these proposed systems correlate with actual neural processes.
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© liquidlibrary/Getty Images/Jupiterimages
Procedural memory involves remembering how to do things, or “procedures” for specific actions. Riding a bicycle, playing an instrument, or solving a mathematical equation would be examples of procedural memory.
Procedural memories are sometimes thought of as “implicit” memories, because they take very little or no conscious effort to retrieve. When you walk up a flight of stairs or ride a bicycle, are you ‘actively’ thinking of how to carry out those acts, or do they sort of happen on their own with very little conscious attention?
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When we retrieve information, it’s never an exact replay of the past. According to constructionist theory, memories are not replicas of past experiences. Instead, we pull up reconstructions of the past that can be distorted and include inaccurate information.
Our poor abilities to retrieve information accurately has been extensively studied, an example of which is the misinformation effect, which occurs when individuals recall of an event is altered by misleading post-event information.
A great example was shown by Loftus and Palmer, in this video [click to play].
Other research has consistently found that people introduce inaccuracies in the simple story-telling we do every day. These findings have helped psychologists understand that memory is not a perfect process and that its more malleable than once thought.
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© AP Images/Marty Lederhandler
Flashbulb Memories – are enduring memories of emotionally charged events that seem permanently burned into the brain. They are not always more accurate than other memories, however. Some flashbulb memories are very accurate over time, while others are subject to distortion.
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© The Charlotte Observer
© Cengage Learning
A misinformation effect may lead to distortions in eyewitness testimony.
In one study, Elizabeth Loftus and her colleagues had subjects view a film of a car accident that occurred at an intersection with a stop sign. Some subjects were then given misleading information telling them that the traffic sign was a yield sign. If you were one of the subjects in this study, do you think your memory would be based on what you had actually seen or on what you were later told you had seen?
Subjects who were not given the false information were much more likely to recall the correct traffic sign.
Eyewitness testimony can be flawed and mistaken because of misinformation effects and other factors affecting reliability of long-term memory. Some of the factors affecting accuracy of eyewitness testimony, as described more fully in the text are:
Ease of recall
Degree of confidence
General knowledge about a subject
Racial identification
Types of questions
Facial characteristics
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Skeptics of Repressed Memory Theory
Do not think individuals are lying on purpose
Therapists may ask leading questions until
the patient inadvertently creates a false memory
Countless studies show that it is easy to create
false memories
Some court cases discredit existence
of repressed memories
Misinformation effect and other research shows that memory is not as reliable as many of us think
Supporters of Repressed Memory Theory
Abuse is more common than we think
Repression is a natural response to trauma
Lab research on implanting memories cannot be compared to emotional events like sexual abuse
No direct and empirical evidence
Many psychologists, especially memory researchers, are skeptical of recovered memories of abuse; however, they do not imply that people reporting these memories are lying or have bad intentions.
Instead, they point to findings on the misinformation effect, suggestibility, and leading questions as contributors to the “uncovering” or repressed memories. Skeptics also highlight cases in which the truth about abuse has been found and the memories proven false.
Of course, rebuttals from therapists are made on the account that repression is a natural response to trauma and dismiss much of the laboratory work on implanting false memories. To say that all recovered memories are false would certainly be incorrect, but great caution must be taken in interpreting these claims. Regardless of one’s standpoint on this issue, recovered memories have generated large amounts of research and will continue to be a focus for memory researchers. We presently lack the tools to distinguish true recovered memories from false ones.
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Module 6.2
Forgetting
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Nonsense Syllables
BAF XOF
CLP MEQ
AYI VIR
Retention of Nonsense Syllables
Retention Interval
20 min
60 min
9 hours
1 day
2 days
5 days
31 days
Retention (%)
0
10
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Although we normally think of forgetting as a “bad thing”, it’s actually quite adaptive. Just imagine the clutter we would have if we remembered everything. But even with its adaptive function, forgetting can be problematic, like when we forget a definition of a term for a test, or where our keys are, or worse.
One of the first to research forgetting was Hermann Ebbinghaus. He used nonsense syllables (random strings of vowels and consonants) as a means of investigating memory.
Interestingly, he himself was the subject of his experiments. In his experiments, he laboriously memorized nonsense syllables and tested his recall after various amounts of time had passed. He then plotted the amount of information (number of nonsense syllables previously learned) he had forgotten in the form of a forgetting curve, like the one shown here. In so doing, he noticed that he forgot many of the syllables shortly after memorizing them. Though we now know that memorizing things with meaning are less forgettable than Ebbinhaus’ forgetting of nonsense syllables, his research spurred psychologists to consider how we measure forgetting.
Ebbinghaus’s theory today is called decay theory, which is the belief that memories gradually fade and deteriorate over time. One limitation of the theory is that it fails to account for unevenness in memory decay. Some memories fade quickly whereas others last a lifetime. Though decay theory has some merit, other factors in forgetting are also involved besides the mere passage of time, such as interference.
Massed versus spaced practice effect – cramming simply does not work as well as regular exposure to information repeatedly, over time.
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© Cengage Learning
Interference theory, which proposes that people forget information because of competition from other material, is a well-documented process and can account for some of our forgetting.
For example, when introducing an interference task of synonyms, high interference occurred, but with numbers that were not associated with the test material, little interference occurred. This type of interference in which new information impairs previously learned information is called retroactive interference.
Proactive interference is just the opposite, when old information interferes with new information, as when memory of your old phone number interferes with recalling your new number.
Interference is the likely explanation of the serial position effect – the tendency to recall first and last items in a list better than items in the middle. Also note the primacy effect and recency effect also come into play when remembering items from a list.
Here we see that how much you retain of a given subject depends on what you study next and what you studied before. Interference effects can work both ways and depend upon the similarity of the material.
To minimize interference effects:
Sleep on it
Rehearse fresh memories
Practice overlearning
Give yourself a break between study periods
Avoid sequential study of similar material
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Forgetting is the result of a failure
to access stored memories
How can the retrieval process
break down?
Encoding failure
Lack of retrieval cues
Tip-of-the-tongue phenomenon
Forgetting may be a product of failure to retrieve information stored in memory. Retrieval can break down if the information was never encoded in the first place (encoding failure), by lack of available retrieval cues, and by the TOT phenomenon (tip-of-the-tongue). Next we take a look at an example of encoding failure.
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© Cengage Learning
Which is the correct image of a penny?
The penny example demonstrates encoding failure, due to a failure to bring this information into memory in the first place due to lack of attention. In effect, we only encode that which is important to know. We can identify a penny without needing to know the particular features of the image.
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Ineffective Encoding
Memories never stored due to lack of attention
© Cengage Learning
We all have handled 1000s of pennies, yet most people cannot identify the correct one.
To understand this strange case and others, we have to understand the three basic processes of memory.
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Repression
A type of defense mechanism involving motivated forgetting of anxiety-evoking material
Can it be adaptive – even psychologically healthy – to forget certain things?
Over a century ago, Freud offered a new explanation for retrieval failures – that we keep distressing impulses and disturbing memories buried in the unconscious through the process of repression.
Freud believed we repress unacceptable aggressive and sexual wishes or impulses the ego deems to be socially unacceptable. Hence, he believed we lack conscious awareness of the basic instincts or drives that lie within the recesses of the unconscious.
Do we also repress memories we are motivated to forget, such as memories of childhood sexual abuse? This theory or forgetting is a hot and controversial topic in present-day psychology, primarily due to a recent surge in lawsuits in which a potential victim claimed that childhood memories of abuse suddenly surfaced, usually in the context of psychotherapy.
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Measures of Retention
Recall Measure
Recognition Measure
How we measure memory has an important bearing on retention.
First is a recall measure, which requires a person to reproduce information on their own without any cues. If asked to memorize 10 words then say them out loud, this would be a recall test.
Second is a recognition measure, which requires a person to select previously learned information from an array of options. All students take part in this process when completing multiple-choice or true-false questions on exams.
Why is it that students typically prefer having multiple choice exams (a recognition measure) to essay exams (a recall measure)?
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The difficulty of a recognition
test can vary
Which is the correct answer?
The fourth president of the United States was:
a. Thomas Jefferson
b. James Monroe
c. John Quincy Adams
d. James Madison
The difficulty of a recognition
test can vary
Which is the correct answer?
The fourth president of the United States was:
a. Jimmy Carter
b. John F. Kennedy
c. Harry Truman
d. James Madison
The difficulty of a recognition test can vary greatly, depending on the number, similarity, and plausibility of the options provided as possible answers. Many students find the question shown to be difficult.
What if the answer choices were Jimmy Carter, John F. Kennedy, Harry Truman, and James Madison? [Click to continue]
Three of these choices are readily dismissed, rendering the question easier to answer.
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Anterograde Amnesia
Memory Loss
Onset of Amnesia
Time
Memory Loss
Retrograde Amnesia
For decades, researchers have tried to trace the physiological processes of memories and even to pinpoint specific memories. As unfortunate as serious head injuries are, they are a rich source of information regarding the anatomy of memory. After serious trauma, some individuals develop amnesia, or extensive memory loss. Similar to how interference is categorized, amnesia can be either retrograde or anterograde.
Retrograde amnesia results in loss of memories for events that occurred prior to the injury whereas anterograde amnesia results in loss of memories for events that occur after the injury. By examining the brain structures and functioning of individuals with serious brain injury, scientists have identified some areas that may be important in the consolidation of memories, such as the hippocampus. Amnesia can also be caused by a psychological trauma, resulting in dissociative amnesia.
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Module 6.3
The Biology
of Memory
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The Engram
Neuronal Networks
The engram, first named by Karl Lashley, is a theoretical trace in the brain where (Lashley believed) memories are stored. In spite of years, in fact a career, spent searching for the engram, Lashley eventually concluded that it does not exist, and that memories are not stored in a singular brain structure.
Today experts believe that memories are stored in memory circuits in the brain that consist of complicated networks of nerve cells. These are called neuronal networks.
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© Roger Harris/Science Source
Several different brain structures are related to our memory skills.
The hippocampus is essential to the formation of new memories of facts, general information, and life experiences.
Damage to the thalamus can result in amnesia.
The amygdala is involved in encoding emotional experiences, such as fear and anger, each of which have a memory component to them.
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Long-Term Potentiation (LTP)
© Eric R. Kandel
Eric Kandel
Karl Lashley’s searched unsuccessfully for the engram, the physical trace or etching in the brain where memory is stored.
More detailed accounts of memory processes at the cellular level over the past 20 years have led to some intriguing theories about how we encode, store, and retrieve memories. Kandel’s work with large sea snails showed that memory formation involves biochemical changes at the synaptic level.
Long-term memory may depend on a process called long-term potentiation, which is a long-lasting increase in neural excitability at synapses along a specific neural pathway. Synaptic connections strengthened by repeated stimulation. Similarly, repeated presentation of the same information may strengthen these neural connections, resulting in better retention. We can call that . . . well, studying.
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Gene regulation
Proteins necessary for making
long-term memories
Work on genetic bases of memory may
lead to treatments for Alzheimer’s and
other memory disorders
If there were a safe and effective memory pill available (there is not, by the way), would you take it? Why or why not?
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Twenty years ago Clive Wearing, who was once an accomplished conductor and musicologist, lost his memory. He now suffers from anterograde amnesia and has less than 30 and occasionally as little as 7 seconds of memory. Still, he has retained his musical abilities and continues to play the piano. Watch him interact with his wife and listen as he and his wife reflect on his condition.
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Applying Psychology in Daily Life
Powering Up
Your Memory
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Acronyms
Acrostics
Popular sayings and rhymes
Visual cues and imagery
Chunking
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Pay attention
Practice to overlearn
Use external memory aids
Link time-based tasks to external cues
Don’t memorize – just Google it
Control stress
Adopt healthy habits
