Don’t forget read Loftus article for next class!

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)

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) –What are some examples of Long-Term Memories?

Some Distinctions in LTM Endel Tulving: There are two broad categories of information that are represented in LTM - Examples: –What did you eat for breakfast? –What is the capital of Canada –Where were you when… –Are maple trees deciduous? –Riding a bike !?

Some Distinctions in LTM Endel Tulving: There are two broad categories of information that are represented in LTM - 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 Endel Tulving: There are two broad categories of information that are represented in LTM - Semantic Memory: memory of facts, knowledge of the world unconnected to an autobiographical event no temporal context

Some Distinctions in LTM A third category may be distinguished: –Example: riding a bike, playing an instrument

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 –This idea is formalized in so-called “connectionist” networks bird canary chicken mockingbird To Kill A Mockingbird racism highschool Martin Luther King skiing Mr. Lacey English

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

Amnesia Loss of memory ability - usually due to lesion or surgical removal of various parts of the brain

Causes of Amnesia Concussion Migraines Hypoglycemia Epilepsy Electroconvulsive shock therapy Specific brain lesions (i.e. surgical removal) Ischemic events Drugs (esp. anesthetics) Infection Psychological Nutritional deficiency Lack of Sleep!

Amnesia Loss of memory ability - usually due to lesion or surgical removal of various parts of the brain Two broad categories: –Retrograde: loss of memories for events prior to damage

Amnesia Loss of memory ability - usually due to lesion or surgical removal of various parts of the brain Two broad categories: –Retrograde: loss of memories for events prior to damage –Anterograde: loss of ability to store new memories of events after damage

Retrograde Amnesia Anterograde Amnesia

Short-term and sensory memory are typically functional

Amnesia - associated brain regions Diencephalic amnesia - damage to the medial thalamus and mammillary nuclei

Amnesia - associated brain regions Diencephalic amnesia - damage to the medial thalamus and mammillary nuclei Medial temporal lobe amnesia - damage to the hippocampus.

Amnesia Hippocampus Thalamus

Diencephalic Amnesia Damage to the medial thalamus and/or mammillary bodies –stroke Korsakoff’s syndrome –Caused by thiamine deficiency as a result of chronic alcoholism

Korsakoff’s Syndrome The Lost Mariner - What happened to Jimmie? What was his life like?

Korsakoff’s Syndrome (The Lost Mariner) Lesions to Medial Thalamus –Results from chronic alcoholism and consequent thiamine deficiency

Korsakoff’s Syndrome (The Lost Mariner) Lesions to Medial Thalamus –Results from chronic alcoholism and consequent thiamine deficiency –Severe anterograde amnesia

Korsakoff’s Syndrome (The Lost Mariner) Lesions to Medial Thalamus –Results from chronic alcoholism and consequent thiamine deficiency –Severe anterograde amnesia –Severe retrograde amnesia extending years before damage

Korsakoff’s Syndrome (The Lost Mariner) Lesions to Medial Thalamus –Results from chronic alcoholism and consequent thiamine deficiency –Severe anterograde amnesia –Severe retrograde amnesia extending years before damage –Confabulation - make up stories to explain absence of memory

Korsakoff’s Syndrome (The Lost Mariner) Lesions to Medial Thalamus –Results from chronic alcoholism and consequent thiamine deficiency –Severe anterograde amnesia –Severe retrograde amnesia extending years before damage –Confabulation - make up stories to explain absence of memory –Often unaware of their deficit

Medial Temporal lobe amnesia Hippocampus is most important site of damage

H. M. Patient H. M. - suffered from extreme epilepsy

H. M. Patient H. M. - bilateral resection of medial temporal lobes (containing hippocampus) –William Beecher Scoville and Brenda Milner - late 1950’s

H. M. Patient H. M. - bilateral resection of medial temporal lobes (containing hippocampus) –William Beecher Scoville and Brenda Milner - late 1950’s –Severe anterograde amnesia

H. M. Patient H. M. - bilateral resection of medial temporal lobes (containing hippocampus) –William Beecher Scoville and Brenda Milner - late 1950’s –Severe anterograde amnesia –Retrograde amnesia for years before surgery

H. M.

Some aspects of memory were spared (at least to some extent)

H. M. Some aspects of memory were spared (at least to some extent) –Procedural memory was largely unaffected - amnesia was largely restricted to episodic memory

H. M. Some aspects of memory were spared (at least to some extent) –Procedural memory was largely unaffected - amnesia was largely restricted to episodic memory –Some implicit awareness of recent events

H. M. Some aspects of memory were spared (at least to some extent) –Procedural memory was largely unaffected - amnesia was largely restricted to episodic memory –Some implicit awareness of recent events –Normal digit span (short-term memory) !

Mirror-drawing Task