Properties of STM 1.Short (scale of seconds) 2.Limited capacity 3.Attentive –Primacy –Recency –Interference (complex and specific)

A Modular Approach to STM Articulatory Loop Central Executive Visuospatial Sketchpad Experiment 1 in the article by Lee Brooks demonstrates a double dissociation between Articulatory Loop and Visuospatial Sketchpad

Model of Memory Turning now to Long-Term Memory Sensory Signals Sensory Memory Short-Term Memory Long-Term Memory ATTENTION REHEARSAL RETRIEVAL

Long-Term Memory Characteristics (intuitive with some introspection): –Persists indefinitely (up to decades!) –Requires no active process of rehearsal (at least that we are conscious of)

Some Distinctions in LTM Declarative Declarative memory is for the sort of information that can become explicit – facts (semantic), autobiographical events (episodic). The term explicit memory is often associated to convey that such memories are accessible to conscious awareness.

Some Distinctions in LTM Non-Declarative Non-declarative memory is for the sort of information that is used without explicit awareness – how to do an action (procedural) Implicit memory is when behaviour is influenced in the absence of conscious memory.

Some Distinctions in LTM Declarative Memory Episodic Memory: memory of an event in your life autobiographical has a temporal context - something about time is encoded along with the memory

Some Distinctions in LTM Declarative Memory Semantic Memory: memory of facts, knowledge of the world unconnected to an autobiographical event no temporal context

CHARACTERISTICSEPISODICSEMANTIC Likelihood of forgettingHighLow UsefulnessLowHigh Recollective experiencePresentAbsent Sensory componentPresentAbsent Presence of emotionPresentAbsent

Some Distinctions in LTM Procedural Memory: memory for actions

Semantic Memory Capacity is huge (unlimited?)

Semantic Memory Structure of encoding is associative

Semantic Memory Structure of encoding is associative –Evidence: Semantic Priming in a Lexical- Decision Task Priming: prior exposure to some stimulus modifies subsequent processing of a target

Semantic Memory Structure of encoding is associative –Evidence: Semantic Priming in a Lexical- Decision Task Lexical Decision Task: Subject is shown a target word or pronounceable non-word (eg. gap or bap) and must respond “word” or “non- word”

Semantic Memory Structure of encoding is associative –Evidence: Semantic Priming in a Lexical- Decision Task manipulation: prime can be either related or unrelated to the target word

Semantic Memory Structure of encoding is associative –Evidence: Semantic Priming in a Lexical- Decision Task result: words are identified faster when preceded by a semantically related prime Prime +Target=Response “space”“gap”fast “truck”“gap”slow

Semantic Memory Structure of encoding is associative –Other evidence: memory can be triggered by recalling related facts

Semantic Memory Structure of encoding is associative –Interpretation: the representation of information in semantic memory is associative: each fact or piece of knowledge is stored along with its relationship to other stored information related items can activate each other which facilitates recall

Episodic Memory Memory for an episode or event in your own life Has temporal context (entails a sense of duration and date) examples: –recall breakfast –what happened this weekend

Recalling Episodic Memory Recall is highly sensitive to context - Similarities in context (especially smell) can trigger vivid recollections

Recalling Episodic Memory Memory is affected by the nature of your engagement with the information Levels-of-Processing Theory

Recalling Episodic Memory Memory is affected by the nature of your engagement with the information Levels-of-Processing Theory –Consider this experiment: List CAT pie PILLOW TREE Method of Learning stating capitals or lower-case repeating words putting words into a sentence Recall is tested some time later.

Recalling Episodic Memory Memory is affected by the nature of your engagement with the information Levels-of-Processing Theory –Consider this experiment: Result: Best recall with “deep” processing Worst recall with “surface” processing List CAT pie PILLOW TREE

Recalling Episodic Memory Memory is affected by the nature of your engagement with the information Interpretation: –the successful use of memory depends on the number of connections that are made between related items and the degree to which these are initially activated

Hypermnesia - S. “Photographic” extreme memory ability (a mnemonist) Able to recall complex test stimuli

Hypermnesia - S. S. used two “strategies” or abilities typical of mnemonists: –Rich synesthesia-like quality to his perception of stimuli - leads to stronger associative links

Hypermnesia - S. S. used two “strategies” or abilities typical of mnemonists: –Rich synesthesia-like quality to his perception of stimuli - leads to stronger associative links –Vivid and elaborate mental imagery of things he should remember

Hypermnesia - S. “ Even numbers remind me of images. Take the number 1. This is a proud, well-built man; 2 is a high-spirited woman; 3 a gloomy person (shy, I don’t Know); 6 a man with a swollen foot...” Luria, A.R. The mind of a mnemonist Luria, A.R. The man with a shattered world. 1972

When You Don’t Remember Two reasons why you don’t remember:

When You Don’t Remember Two reasons why you don’t remember: Unavailable –It wasn’t successfully encoded - something went wrong while you were studying

When You Don’t Remember Two reasons why you don’t remember: Unavailable –It wasn’t successfully encoded - something went wrong while you were studying Inaccessible –memory is stored but cannot be retrieved, perhaps because appropriate connections aren’t being made

Implicit and Explicit Memory Are all memories explicit? Is all information stored in the brain subject to conscious scrutiny?

Implicit and Explicit Memory Are all memories explicit? Is all information stored in the brain subject to conscious scrutiny? Implicit Memory refers to encoded memories that are not part of the “contents” of awareness

Implicit and Explicit Memory How can we know whether memory is stored/recalled implicitly or explicitly?

Implicit Memory Consider the following distinction in recalling items from a list of words:

Implicit Memory Consider the following distinction in recalling items from a list of words: Free Recall - subjects can be asked to simply recall and report as many items as possible - these items are accessible as explicit memory

Implicit Memory Consider the following distinction in recalling items from a list of words: Implicit Recall - subjects can be asked to complete a word stem with any word that comes to mind after reading a list of words (no mention of testing memory!) __ack

Implicit Memory Consider the following distinction in recalling items from a list of words: Implicit Recall - subjects can be asked to complete a word stem with any word that comes to mind after reading a list of words (no mention of testing memory!) But how do you know that information is stored/recalled implicitly? Couldn’t it be explicit?

Implicit Memory Consider the following distinction in recalling items from a list of words: Twist - require subject to complete stem with a word that wasn’t on the list - if a word from the list is used preferentially, it was remembered implicitly

Implicit Memory Consider the implications regarding the nature of consciousness and the connection between neural activity and awareness

Implicit Memory Consider the implications regarding the nature of consciousness and the connection between neural activity and awareness Not all of the activity in your brain generates experience - some is “sub”conscious or non-conscious

Recalling Episodic Memory Recall is a generative processes rather than simply calling up stored data

Recalling Episodic Memory Recall is a generative processes rather than simply calling up stored data Evidenced by the fact that episodic memories can be distorted or completely false under certain circumstances

Recalling Episodic Memory Misinformation Effect - exposure to information subsequent to storage of memory can alter the contents of the memory

Recalling Episodic Memory Misinformation Effect Consider the following example: –Subjects were shown a video depicting a car accident

Recalling Episodic Memory Misinformation Effect Consider the following example: –Subjects were shown a video depicting a car accident –Then given the following question: “How fast were the vehicles going when they ______”

Recalling Episodic Memory Misinformation Effect Consider the following example: –Subjects were shown a video depicting a car accident –Then given the following question: “How fast were the vehicles going when they ______” –Different subjects were asked questions that differed in the “magnitude” of the final word

Recalling Episodic Memory Misinformation Effect Consider the following example: –Subjects were shown a video depicting a car accident –Then given the following question: “How fast were the vehicles going when they ______” –Different subjects were asked questions that differed in the “magnitude” of the final word –The possible words were: Contacted, Hit, Bumped, Collided, and Smashed

Recalling Episodic Memory Misinformation Effect Consider the following example: –Average estimated velocity depended on the nature of the question

Recalling Episodic Memory Misinformation Effect Interpretation: –Episodic memory can be distorted by subsequent information

Recalling Episodic Memory Memory for episodes in life can be illusory

Recalling Episodic Memory Memory for episodes in life can be illusory Consider the example in Loftus’ article: –participant was induced to have an episodic memory of being lost in a mall

Recalling Episodic Memory Memory for episodes in life can be illusory Consider the example in Loftus’ article: –participant was induced to have an episodic memory of being lost in a mall –Even when told the memory is a false one, the participant had difficulty recognizing it as an invalid memory

Recalling Episodic Memory False Memories may arise when details of a crime are in question as in eye- witness testimony or repressed memories of abuse during childhood

Repressed Memories Elizabeth Loftus

“Derepressed memories” Loftus opens with several examples of court cases that involve “derepressed memories” What is a repressed memory? What is a derepressed memory?

Loftus’ position in this article Loftus does not reject the notion of repressed memories –18% - 59% of abuse survivors report having regained access to previously repressed memories

Loftus’ position in this article Loftus does not reject the notion of repressed memories –18% - 59% of abuse survivors report having regained access to previously repressed memories What does Loftus challenge?

Loftus’ position in this article Loftus does not reject the notion of repressed memories –18% - 59% of abuse survivors report having regained access to previously repressed memories What does Loftus challenge? …That all “de-repressed” memories are accurate memories.

High Stakes Survivor of real abuse might struggle for years or decades with consequences and need to confront the repressed memory in order to recover emotionally False accusation could tear family apart and send an innocent person to jail

What’s the issue? What does Loftus express concern about regarding the derepression of memories?

What’s the issue? What does Loftus express concern about regarding the derepression of memories? –reality of the memory is in question if it is recalled under certain circumstances

What’s the issue? What does Loftus express concern about regarding the derepression of memories? –reality of the memory is in question if it is recalled under certain circumstances What is the course of events that Loftus finds worrisome?

What’s the issue? What does Loftus express concern about regarding the derepression of memories? –reality of the memory is in question if it is recalled under certain circumstances What is the course of events that Loftus finds worrisome? Therapist or Popular Book suggests that patient consider possibility of abuse Patient engages in intense effort to recall An explicit episodic memory is achieved This memory might be false!

What’s the issue? So we potentially have a situation in which someone who is having troubles in life and is seeking answers is told to determine whether or not memories for abuse exist What are some techniques that are used to “assist” recollection?

What’s the issue? So we potentially have a situation in which someone who is having troubles in life and is seeking answers is told to determine whether or not memories for abuse exist What are some techniques that are used to “assist” recollection? –hypnosis, imagery, dream analysis, story telling –Loftus presents evidence that such processes may lead to invalid memories or overconfidence in the validity of memories

Conclusion: We cannot know with certainty (without corroborating evidence) whether a derepressed memory is true Therapists should engage in probing this possibility very carefully –avoiding suggestive questions –remaining unconvinced without corroborating evidence –being “gently confrontational” to encourage patient to consider the possibility that the events didn’t happen