CH. 7. Interconnections between Acquisition and Retrieval Flashcards
Korsakoff’s Syndrome
KORSAKOFF’S SYNDROME – Those with this syndrome can’t consciously recall what happened in the recent past yet the memories were still present unconsciously – detected through indirect methods where the patient would share info from these memories that they didn’t even know they had.
- These observations strongly suggest that there must be different types of memory — including a type that’s massively disrupted in these amnesic patients, yet one that is apparently intact
Learning as Preparation for Retrieval
LEARNING AS PREPARATION FOR RETRIEVAL – How you learn something will largely determine how easy it is to retrieve the learned information.
- Information that was learned with engagement and understanding will have formed rich connections and many RETRIEVAL PATHS and will be easily retrieved. Not so much for information that was only superficially remembered.
- Different ways to retrieve information from memory:
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RECALL – Give an answer with no clues.
- EX: “What was the name of your tenth-grade homeroom teacher?”
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RECOGNITION – Give an answer with clues provided (easier than Recall)
- EX: “Was the name perhaps Miller?”
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RECALL – Give an answer with no clues.
Crucial Role of Retrieval Paths – When you’re learning, you’re making connections between the newly acquired material and other information already in your memory.
- These connections make the new knowledge “findable” later on. Specifically, the connections serve as:
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RETRIEVAL PATHS – When you want to locate information in memory, you travel on those paths, moving from one memory to the next until you reach the target material.
- The more paths you have to what you’re looking for, the easier it will be to find it.
- These retrieval paths have a starting point and an ending point: The path leads you from Point A to Point B. That’s useful if you want to move from A to B, but what if you’re trying to reach B from somewhere else? More paths are better.
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RETRIEVAL PATHS – When you want to locate information in memory, you travel on those paths, moving from one memory to the next until you reach the target material.
Context-Dependent Learning
CONTEXT-DEPENDENT LEARNING – Things learned in a specific environment or condition are best recalled under the same conditions.
- This is because the connections made while learning are often related to the learning environment.
- But what is important is the psychological context, NOT the physical context.
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EX: In one study, researchers reported the same pattern if learning and testing took place in different rooms — with the rooms varying in appearance, sounds, and scent. In this study, though, there was an important twist: In one version of the procedure, the participants learned materials in one room and were tested in a different room.
- Just before testing, however, the participants were urged to think about the room in which they had learned — what it looked like and how it made them feel. When tested, these participants performed as well as those for whom there was no room change.
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What matters, therefore, is not the physical context but the psychological context:
- A result that’s consistent with our account of this effect.
- As a result, you can get the benefits of context-dependent learning through a strategy of:
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CONTEXT REINSTATEMENT – re-creating the thoughts and feelings of the learning episode even if you’re in a very different place at the time of recall.
- That’s because what matters for memory retrieval is the mental context, not the physical environment itself.
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CONTEXT REINSTATEMENT – re-creating the thoughts and feelings of the learning episode even if you’re in a very different place at the time of recall.
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EX: In one study, researchers reported the same pattern if learning and testing took place in different rooms — with the rooms varying in appearance, sounds, and scent. In this study, though, there was an important twist: In one version of the procedure, the participants learned materials in one room and were tested in a different room.
Encoding Specificity
ENCODING SPECIFICITY – reminds us that what you encode (i.e., place into memory) is indeed specific — not just the physical stimulus as you encountered it, but the stimulus together with its context.
- Your memory contains both the information you were focusing on during learning and the highways you’ve now built, leading toward that information.
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MEMORY CONNECTIONS – can of course influence your search for the target information.
- Connections can do more: They can also change the meaning of what is remembered.
- “memory plus this set of connections” has a different meaning from “memory plus that set of connections.”
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EX: In one experiment participants read target words (e.g., “piano”) in one of two contexts: “The man lifted the piano” or “The man tuned the piano.” In each case, the sentence led the participants to think about the target word in a particular way, and it was this thought that was encoded into memory. In other words, what was placed in memory wasn’t just the word “piano.” Instead, what was recorded in memory was the idea of “piano as something heavy” or “piano as musical instrument.”
- This difference in memory content became clear when participants were later asked to recall the target words. If they had earlier seen the “lifted” sentence, they were likely to recall the target word if given the cue “something heavy.” The hint “something with a nice sound” was much less effective. But if participants had seen the “tuned” sentence, the result reversed: Now, the “nice sound” hint was effective, but the “heavy” hint wasn’t.
- The cue was effective only if it was congruent with what was stored in memory.
- This difference in memory content became clear when participants were later asked to recall the target words. If they had earlier seen the “lifted” sentence, they were likely to recall the target word if given the cue “something heavy.” The hint “something with a nice sound” was much less effective. But if participants had seen the “tuned” sentence, the result reversed: Now, the “nice sound” hint was effective, but the “heavy” hint wasn’t.
- EX: It’s as if you had learned the word “other” and were later asked whether you’d been shown the word “the.” In fact, “the” does appear as part of “other” — because the letters t h e do appear within “other.” But it’s the whole that people learn, not the parts. Therefore, if you’ve seen “other,” it makes sense to deny that you’ve seen “the” — or, for that matter, “he” or “her” — even though all these letter combinations are contained within “other.”
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MEMORY CONNECTIONS – can of course influence your search for the target information.
REMEMBERING “RE-CREATES” AN EARLIER EXPERIENCE – Brain areas activated when you’re remembering a target overlap considerably with the brain areas that were activated when you first encountered the target.
Memory Network
MEMORY NETWORK – Memory is best thought of as a vast network of ideas.
- These ideas are represented – think of these representations as NODES within the network. When you are looking for a specific idea from your memory, you are looking for a specific NODE.
- The NODES are like light bulbs that can be activated by incoming electricity.
- These NODES are tied to each other via connections called ASSOCIATIONS or ASSOCIATIVE LINKS.
- Imagine these associative links as wires that carry the electricity.
- These NODES are tied to each other via connections called ASSOCIATIONS or ASSOCIATIVE LINKS.
- The NODES are like light bulbs that can be activated by incoming electricity.
SPREADING ACTIVATION:
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NODES becomes activated when it has received a strong enough input signal.
- Once a node has been activated, it can activate other nodes – similar to how neurons that have fired can stimulate other neurons, creating a neural path.
- Nodes receive activation from their neighbors, and as more and more activation arrives at a particular node, the ACTIVATION LEVEL for that node increases.
- Eventually, the activation level will reach the node’s RESPONSE THRESHOLD – at which point, the NODE FIRES.
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This firing has several effects:
- The node will now itself be a source of activation, sending energy to its neighbors and activating them.
- FIRING of the node will draw attention to that node – this is what it means to “find” a node within the network.
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This firing has several effects:
- Activation levels below the response threshold that do NOT fire, so-called SUBTHRESHOLD ACTIVATION, also play an important role.
- Activation accumulates, so that two subthreshold inputs may add together, in a process of SUMMATION, and bring the node to THRESHOLD – at which point it would FIRE.
- Likewise, if a node has been partially activated recently, it is in effect already “warmed up,” (primed) so that even a weak input will now be sufficient to bring it to the threshold.
- Eventually, the activation level will reach the node’s RESPONSE THRESHOLD – at which point, the NODE FIRES.
- Our current discussion also parallels how a network of detectors might function in object recognition.
- Long-term storage.
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SPREADING ACTIVATION – Activation travels from node to node via associative links. As each node becomes activated and fires, it serves as a source for further activation, spreading onward through the network.
- Activation spreads out from its starting point in all directions simultaneously, flowing through whatever connections are in place.
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INTERSECTING RETRIEVAL CUES:
- “What’s the capital of South Dakota?” – No idea.
- But then you might remember if given the cue “Is it perhaps a man’s name?
- Maybe you’re not very familiar with South Dakota.
- This weak connection will do a poor job of carrying the activation, with the result that only a trickle of activation will flow into the “Pierre” nodes, and so these nodes won’t reach threshold and won’t be “found.”
- HOWEVER, if you’re told, “South Dakota’s capital is also a man’s name,” this will activate the man’s name node. As a result, activation will spread out from this source at the same time that activation is spreading out from the South Dakota nodes.
- Therefore, the nodes for pierre will now receive activation from two sources simultaneously, and this will probably be enough to lift the nodes’ activation to threshold levels.
- In this way, question-plus-hint (recognition) accomplishes more than the question by itself (recall).
- This is why recognition is easier than recall.
- “What’s the capital of South Dakota?” – No idea.
SEMANTIC PRIMING:
SUMMATION OF SUBTHESHOLD ACTIVATION – The insufficient activation received from one source can add to the insufficient activation received from another source.
- The two can combine to activate the target nodes.
LEXICON-DECISION TASK – Participants are shown a series of letter sequences on a computer screen. Some of the sequences spell words; other sequences aren’t words (e.g., “blar, plome”). The participant’s task is to hit a “yes” button if the sequence spells a word and a “no” button otherwise. Presumably, they perform this task by “looking up” these letter strings in their “mental dictionary,” and they base their response on whether or not they find the string in the dictionary.
- We can therefore use the participants’ speed of response in this task as an index of how quickly they can locate the word in their memories.
- Presented participants with pairs of letter strings, and participants had to respond “yes” if both strings were words and “no” otherwise.
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EX: Consider a trial in which participants see a related pair, like “bread, butter.” To choose a response, they first need to “look up” the word “bread” in memory.
- Bread (the first word in the pair) has just been activated. This will, we’ve hypothesized, trigger a spread of activation outward from this node, bringing activation to other, nearby nodes. These nearby nodes will surely include butter,
- The closeness of the connection between the “bread” and “butter” to be primed once “bread” is found, so the “butter” will require minimal activation at that point, speeding up the pair recognition.
- This priming will NOT occur with unrelated words and so will take longer to determine if they were both words.
- Bread (the first word in the pair) has just been activated. This will, we’ve hypothesized, trigger a spread of activation outward from this node, bringing activation to other, nearby nodes. These nearby nodes will surely include butter,
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EX: Consider a trial in which participants see a related pair, like “bread, butter.” To choose a response, they first need to “look up” the word “bread” in memory.
SEMANTIC PRIMING – A specific prior event (in this case, presentation of the first word in the pair) will produce a state of readiness (and, therefore, faster responding)
- Priming results from the fact that the two words in the pair are related in meaning.
- One node activating nearby nodes
- People have some degree of control over the starting points for their memory searches, relying on the processes of reasoning
- Once the spreading activation has begun, people have the option of “shutting down” some of this spread if they’re convinced that the wrong nodes – in other words, they are getting the wrong answer.
- Spreading activation is a crucial mechanism.
Different Forms of Memory Testing
DIFFERENT FORMS OF MEMORY TESTING
- Understanding consists of seeing how new material is connected to other things you know.
- The paths through memory have both a starting point and an end point. Therefore, retrieval paths will be helpful only if you’re at the appropriate starting point; this is the basis for the advantage produced by CONTEXT REINSTATEMENT.
- What these paths really are – Connections that carry activation from one memory to another.
- Two modes of retrieval — RECALL and RECOGNITION — are fundamentally different from each other.
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Recall requires memory search because you have to come up with the sought-after item on your own.
- Recall depends heavily on the memory connections we’ve been emphasizing so far.
- Recognition, in contrast, often depends on a sense of familiarity.
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Recall requires memory search because you have to come up with the sought-after item on your own.
- SOURCE MEMORY – Recollection of the source of your current knowledge.
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RECOGNITION without SOURCE MEMORY leads to a strong sense of FAMILIARITY.
- You ATTRIBUTE the familiarity to an earlier encounter, but you don’t really know what the context of that earlier encounter entails.
FAMILIARITY AND SOURCE MEMORY:
SOURCE MEMORY – This Is actually a type of recall.
FAMILIARITY – it’s possible for an event to be familiar without any source memory, AND it’s possible for you to have source memory without any familiarity.
REMEMBER/KNOW DISTINCTION – This involves pressing one button (to indicate “remember”) if they actually recall the episode of encountering a particular item, and pressing a different button (“know”) if they don’t recall the encounter but just have a broad feeling that the item must have been on the earlier list. With one response, participants are indicating that they have a source memory; with the other, they’re indicating an absence of source memory.
- Basically, a participant using the “know” response is saying, “This item seems familiar, so I know it was on the earlier list even though I don’t remember the experience of seeing it”
Researchers can use fMRI scans to monitor participants’ brain activity while they’re taking these memory tests, and the scans indicate that “remember” and “know” judgments depend on different brain areas.
- Familiarity and source memory can also be distinguished during learning.
- If certain brain areas (e.g., the rhinal cortex) are especially active during learning, then the stimulus is likely to seem familiar later on.
- In contrast, if other brain areas (e.g., the hippocampal region) are particularly active during learning, there’s a high probability that the person will indicate source memory for that stimulus when tested late.
- Activity in the hippocampus is probably helping to create the memory connections we’ve been discussing all along, and it’s these connections, we’ve suggested, that promote source memory.
Implicit Memory
IMPLICIT MEMORY – Memory of items that exists but is not available to our consciousness. Nevertheless, it still influences our thoughts and feelings.
- We can expose someone to an event, and then later re-expose her to the same event and assess whether her response on the second encounter is different from the first.
- Specifically, we can ask whether the first encounter somehow primed the person — got her ready — for the second exposure. If so, it would seem that the person must retain some record of the first encounter — she must have some sort of memory.
- This is what creates FAMILIARITY.
- Specifically, we can ask whether the first encounter somehow primed the person — got her ready — for the second exposure. If so, it would seem that the person must retain some record of the first encounter — she must have some sort of memory.
LEXICAL DECISION TASK – shown a series of letter strings and, for each, must indicate (by pressing one button or another) whether the string is a word or not. Some of the letter strings in the lexical-decision task are duplicates of the words seen in the first part of the experiment.
- Lexical Decisions are quicker if the person has recently seen the test word.
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Lexical Decision shows the pattern we called “REPETITION PRIMING”.
- At a sufficient delay, the direct memory test is likely to show that the participants have completely forgotten the words presented earlier; their recognition performance is essentially random. According to the lexical-decision results, however, the participants still remember the words — and so they show a strong priming effect.
- Even after a duration where ALL words had been consciously forgotten, memory for the words still existed subconsciously.
- An argument in favor of intuition is supported by unconscious knowledge and experience.
- Even after a duration where ALL words had been consciously forgotten, memory for the words still existed subconsciously.
- Participants are influenced by a specific past experience that they seem (consciously) not to remember at all. A pattern referred to as MEMORY WITHOUT AWARENESS.
- At a sufficient delay, the direct memory test is likely to show that the participants have completely forgotten the words presented earlier; their recognition performance is essentially random. According to the lexical-decision results, however, the participants still remember the words — and so they show a strong priming effect.
WORD- STEM COMPLETION – Participants are given three or four letters and must produce a word with this beginning.
- If, for example, they’re given cla-, then “clam” or “clatter” would be acceptable responses, and the question of interest for us is which of these responses the participants produce.
- It turns out that people are more likely to offer a specific word if they’ve encountered it recently; once again, this priming effect is observed even if participants, when tested directly, show no conscious memory of their recent encounter with that word.
Distinguish two types of memory:
EXPLICIT MEMORIES – Are usually revealed by DIRECT MEMORY TESTING – testing that urges participants to remember the past.
- Recall is a direct memory test; so is a standard recognition test.
IMPLICIT MEMORIES – Are typically revealed by INDIRECT MEMORY TESTING and are often manifested as priming effects.
- In this form of testing, participants’ current behavior is demonstrably influenced by a prior event, but they may be unaware of this.
- Lexical decision, word-stem completion, and many other tasks provide indirect means of assessing memory.
FALSE FAME EXPERIMENT:
- Classic research study, Jacoby, Kelley, Brown, and Jasechko (1989) presented participants with a list of names to read out loud.
- This misattribution is possible only because the feeling of familiarity produced by these names was relatively vague, and therefore open to interpretation.
- The suggestion, then, is that implicit memories may leave people with only a broad sense that a stimulus is somehow distinctive — that it “rings a bell” or “strikes a chord.”
- What happens after this depends on how they interpret that feeling.
- Just as the participants interpreted the familiarity of the names in the context of the experiment which was supposed to be about famous people.
Implicit Memory and the “Illusion of Truth”
IMPLICIT MEMORY AND THE “ILLUSION OF TRITH” – How broad is this potential for misinterpreting an implicit memory?
- Participants in one study heard a series of statements and had to judge how interesting each statement was.
- The question of interest is how sentence credibility is influenced by sentence familiarity.
- The result was a propagandist’s dream: Sentences heard before were more likely to be accepted as true; that is, familiarity increased credibility
- This effect was found even when participants were warned in advance not to believe the sentences in the first list.
Someone who lacks this explicit memory?
- EX: This person will have no conscious recall of the episode in which he last encountered this sentence (i.e., will have no source memory), and so he won’t know whether the assertion came from a man or a woman. He therefore can’t use the source as a basis for judging the truthfulness of the sentence. But he might still have an implicit memory for the sentence left over from the earlier exposure (“Gee, that statement rings a bell”), and this might increase his sense of the statement’s credibility (“I’m sure I’ve heard that somewhere before; I guess it must be true”)
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ILLUSION OF TRUTH – Familiar statements were subsequently judged to be more credible than sentences never heard before.
- If you don’t remember the source of the information then you can’t use that source to give you clues about the information that you find familiar. That means that your interpretation of familiarity defaults to the available context.
- This means that you are at the mercy of the context that might have been created for you by someone who did not have your best interest at heart (e.g. a politician, advertised, or propagandist).
- If you don’t remember the source of the information then you can’t use that source to give you clues about the information that you find familiar. That means that your interpretation of familiarity defaults to the available context.
- This will be true even if a newspaper merely raised a question;
- It will be true even if the allegation came from a disreputable source.
ATTRIBUTING IMPLICIT MEMORY TO THE WRONG SOURCE:
SOURCE CONFUSION – The participants correctly realized that one of the faces in the lineup looked familiar, but they were confused about the source of the familiarity. They falsely believed they had seen the person’s face in the original “crime,” when, in truth, they’d seen that face only in a subsequent photograph.
- In fact, the likelihood of this error was quite high, with 29% of the participants (falsely) selecting from the lineup an individual they had seen only in the mug shots.
Cryptoplagiarism
CRYPTOPLAGIARISM – Inadvertent copying that is entirely unwitting and uncontrollable, and usually copying that comes with the strong sense that you’re the inventor of the idea, even though you’ve taken the idea from someone else.
- Subconscious plagiarism.
This pattern fits well with the chapter’s discussion of implicit memory.
- The participants in this study (and others) have lost their explicit memory of the earlier episode in which they encountered someone else’s ideas.
- Even so, an implicit memory remains and emerges as a priming effect. With certain words primed in memory, participants are more likely to produce those words when asked — with no realization that their production has been influenced by priming.
- And you may not realize either that the idea “came to you” because of a priming effect or that the idea seemed workable because of the “warm-up” provided by the earlier conversation.
Theoretical Treatments of Implicit Memory
THEORETICAL TREATMENTS OF IMPLICIT MEMORY – People are often better at remembering that something is familiar than they are at remembering why it is familiar.
- To have a sense of familiarity without source memory.
- Also why it’s possible to be correct in judging familiarity but mistaken in judging source.
- “MEMORY WITHOUT AWARENESS” describe these memories as implicit memories.
PROCESSING FLUENCY:
- When a stimulus arrives in front of your eyes, it triggers certain detectors, and these trigger other detectors until you recognize the object.
- We can think of this sequence as involving a “flow” of activation that moves from detector to detector.
PROCESSING PATHWAY – The sequence of detectors, and the connections between detectors, that the activation flows through in recognizing a specific stimulus.
- Remembering often involves the activation of a node, and this node triggers other, nearby, nodes so that they become activated; they trigger still other nodes, leading eventually to the information you seek in memory.
- The use of a processing pathway strengthens that pathway because continued activation PRIMES the pathway.
- Likewise, connections (between detectors or nodes) grow stronger with use.
- As a result, the pathway will be a bit more efficient, a bit faster, the next time you use it.
- Theorists describe this fact by saying that use of a pathway increases the pathway’s PROCESSING FLUENCY — the speed and ease with which the pathway will carry activation.
People are sensitive to the degree of processing fluency.
- When a stimulus is easy to perceive, you don’t experience something like “That stimulus sure was easy to recognize!” Instead, you merely register a vague sense of specialness. You feel that the stimulus “rings a bell.”
What makes a stimulus feel “special” may not be fluency itself.
- Instead, people seem sensitive to changes in fluency.
- EX: They notice if it’s a little harder to recognize a face this time than it was in the past).
- People also seem to notice discrepancies between how easy (or hard) it was to carry out some mental step and how easy (or hard) they expected it to be.
- In other words, a stimulus is registered as distinctive (harder than expected), or “rings a bell,” (easier than expected) when people detect a change or a discrepancy between experience and expectations.
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When a stimulus feels special (because of a change in fluency, or a discrepancy between the fluency expected and the fluency experienced), you often want to know why.
- The specialness will be (accurately) interpreted as familiarity and attributed to the correct source. (“That woman seems distinctive, and I know why: It’s the woman I saw yesterday in the dentist’s office.”)
- Because you have the relevant source memory — and this memory guides you in deciding why a stimulus (a face, a song, a smell) seems to stand out.you make a reasonable inference, perhaps guided by the context. (“I don’t remember where I heard this joke before, but it’s the sort of joke that Conor is always telling, so I bet it’s one of his and that’s why the joke is familiar.”)
- The specialness will be (accurately) interpreted as familiarity and attributed to the correct source. (“That woman seems distinctive, and I know why: It’s the woman I saw yesterday in the dentist’s office.”)
Nature of Familiarity
NATURE OF FAMILIARITY – You might think that familiarity is simply a feeling that’s produced more or less directly when you encounter a stimulus you’ve met before.
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“Familiarity” is more like a conclusion that you draw rather than a feeling triggered by a stimulus.
- Specifically, the evidence suggests that a stimulus will seem familiar whenever the following list of requirements is met:
- First, you have encountered the stimulus before.
- Second, because of that prior encounter (and the “practice” it provided), your processing of that stimulus is now faster and more efficient; there is, in other words, an increase in processing fluency.
- Third, you detect that increased fluency, and this leads you to register the stimulus as somehow distinctive or special.
- Fourth, you try to figure out why the stimulus seems special, and you reach a particular conclusion — namely, that the stimulus has this distinctive quality because it’s a stimulus you’ve met before in some prior episode.
- You’re likely to arrive at this conclusion and decide a stimulus is familiar only when you have supporting information.
- This sort of illusion of familiarity can be produced if the processing of a completely novel stimulus is more fluent than you expected.
- Specifically, the evidence suggests that a stimulus will seem familiar whenever the following list of requirements is met:
- Your processing of the stimulus is unexpectedly fluent; you seek an attribution for this fluency, and you’re fooled into thinking the stimulus is familiar — so you say you’ve seen the stimulus before, when in fact you haven’t.
THE STEPS LEADING TO A JUDGEMENT OF FAMILIARITY:
Exposure to a stimulus → Practice in perceiving → Fluency → Stimulus registered as “special” → →Attribution of fluency, perhaps attribution to a specific prior event → “Familiarity”
THE CREATION OF ILLUSION OF FAMILIARITY:
Manipulation of stimulus presentation designed to make perceiving easier → Fluency → Stimulus registered as “special” → Attribution of fluency, perhaps attribution to a specific prior event → “Familiarity”
- In the top line, practice in perceiving leads to fluency, and if the person attributes the fluency to some specific prior event, the stimulus will “feel familiar.”
- The bottom line, however, indicates that fluency can be created in other ways: by presenting the stimulus more clearly or for a longer exposure. Once this fluency is detected, though, it can lead to steps identical to those in the top row. In this way, an “illusion of familiarity” can be created.
Hierarchy of Memory Types
HIERARCHY OF MEMORY TYPES:
- Memory
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Explicit Memory – Conscious:
- Episodic Memory – Memory for specific events.
- Semantic Memory – General knowledge, not tied to any time or place.
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Implicit Memory – Revealed by indirect tests:
- Procedural Memory – Knowing how (i.e., memory for skills).
- Priming – Changes in perception and belief caused by previous experience.
- Perceptual Learning – Recalibration of perceptual systems as a result of experience.
- Classical Conditioning – Learning about associations among stimuli.
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Explicit Memory – Conscious:
Amnesia
AMNESIA – Loss of memory.
- Many cases of amnesia involve both retrograde and anterograde memory loss.
- Some forms of amnesia are RETROGRADE, meaning that they disrupt memory for things learned prior to the event that initiated the amnesia
RETROGRADE AMNESIA – often caused by blows to the head; the afflicted person is unable to recall events that occurred just before the blow.
ANTEROGRADE AMNESIA – The reverse effect, causing disruption of memory for experiences after the onset of amnesia.
DISRUPTED EPISODIC MEMORY, BUT SPARED SEMANTIC MEMORY:
EPISODIC MEMORY – Memory of life’s events.
SEMANTIC MEMORY – Memory of generic information.
Similar amnesia has been found in patients who have been longtime alcoholics.
- most alcoholic beverages are missing several key nutrients, including vitamin B1 (thiamine). As a result, longtime alcoholics are vulnerable to problems caused by thiamine deficiency, including the disorder known as Korsakoff’s syndrome.
KORSAKIFF’s SYNDROME – They typically have no problem remembering events that took place before the onset of alcoholism. They can also maintain current topics in mind as long as there’s no interruption. New information, though, if displaced from the mind, seems to be lost forever.
ANTEROGRADE AMNESIA: WHAT KIND OF MEMORY IS DISRUPTED?
- Édouard Claparède (1911/1951) reported the following incident.
- He was introduced to a young woman suffering from Korsakoff’s amnesia, and he reached out to shake her hand. However, Claparède had secretly positioned a pin in his own hand so that when they clasped hands the patient received a painful pinprick.
- The next day, Claparède returned and reached out to shake hands with the patient.
- But just before their hands touched, the patient abruptly pulled back and refused to shake hands with Claparède. He asked her why, and after some confusion the patient said vaguely, “Sometimes pins are hidden in people’s hands.”
- Korsakoff’s patients are unable to recall episodes they’ve experienced; they seem to have no explicit memory. But if they’re tested indirectly, we see clear indications of memory — and so these patients seem to have intact implicit memories.
- In fact, in many tests of implicit memory, amnesic patients seem indistinguishable from ordinary individuals.
- He was introduced to a young woman suffering from Korsakoff’s amnesia, and he reached out to shake her hand. However, Claparède had secretly positioned a pin in his own hand so that when they clasped hands the patient received a painful pinprick.
Can There Be Explicit Memory without Implicit?
- We can also find patients with the reverse pattern — intact explicit memory, but impaired implicit
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Patient who had suffered brain damage to the hippocampus but not the amygdala
- Showed a Fear response but NOT EXPLICIT MEMORY.
- With a second patient who had the opposite pattern:
- Damage to the amygdala but not the hippocampus.
- Who showed No Fear response but did show EXPLICIT MEMORY.
- Damage to the amygdala but not the hippocampus.
- These patients were exposed to a series of trials in which a particular stimulus (a blue light) was reliably followed by a loud boat horn.
- Patient with damage to the hippocampus did show a fear reaction to the blue light
- Patients with damage to the amygdala showed the opposite pattern. She was able to report that just one of the lights had been associated with the horn and that the light’s color had been blue — demonstrating fully intact explicit memory. When presented with the blue light, however, she showed no fear response.
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Patient who had suffered brain damage to the hippocampus but not the amygdala
- IMPLICIT MEMORY is associated with the AMYGDALA.
- EXPLICIT MEMORY is associated with the HIPPOCAMPUS.
Optimal Learning
OPTIMAL LEARNING
Someone who suffers hippocampal damage will probably appear normal on an indirect memory test but seem amnesic on a direct test, while someone who suffers amygdala damage will probably show the reverse pattern.
If you’re going to be tested explicitly, you want to learn the material in a way that prepares you for that form of retrieval.
- If you’ll need source memory, then you want one type of preparation;
- If you’ll need familiarity, you might want a different type of preparation.
- The problem, though, is that during learning, you often don’t know how you’ll be approaching the material later.
The best strategy in learning would be to use multiple perspectives.
Familiarity can be treacherous
FAMILIARITY CAN BE TREACHEROUS:
- We can’t think of familiarity just as a “feeling” somehow triggered by a stimulus.
- Instead, familiarity seems more like a conclusion that you draw at the end of a many-step process.
- As a result of these complexities, errors about familiarity are possible: cases in which a stimulus feels familiar even though it’s not, or cases in which you correctly realize that the stimulus is familiar but then make a mistake about why it’s familiar.
- This sense of familiarity is an unreliable guide in choosing a response.
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**We noted that one of the most common study strategies used by students is to read and reread their notes, or read and reread the textbook. This strategy turns out not to help memory very much, and other strategies are demonstrably better.
- But, in addition, the rereading strategy can actually hurt you. Thanks to the rereading, you become more and more familiar with the materials, which makes it easy to interpret this familiarity as mastery. But this is a mistake, and because of the mistake, familiarity can sometimes lead students to think they’ve mastered material when they haven’t, causing them to end their study efforts too soon.
- You’ll do a much better job of assessing your own mastery if, rather than relying on familiarity, you give yourself some sort of quiz.
- You don’t want to ignore familiarity, because sometimes it’s all you’ve got.
- It may be best to regard familiarity just as a weak clue about the past and not as a guaranteed indicator.