Page 1Memory Systems and NeuropsychologyMarch 29, 2001Collins & Quillian Hierarchical ModelLiving thingAnimalPlantBirdFishChickenCanaryis ais ais ais ais ais asingyellowcaniswingshasfeathershasskinmovehascanbreatheeatmustmust1. Accounts for property inheritance (“does a canary breathe?”)2. Accounts for identity questions (“is a canary an animal?”)Collins & Loftus"Clinton"TimeClintonUS CongressWhite HouseClintonUS CongressWhite HouseClintonUS CongressWhite HouseSpreading activation along nodes.ExampleSame informationAllows retrieval of properties.Allows content-addressable storage (e.g. activate 40’s and Jet)Accounts for typicalityCreates defaultsResistant to faulty inputDistributed representationvanillachocolatestrawberrycoffeevanillachocolatestrawberrycoffeerocky roadtutti-fruittiLocal representationDistributed representationLocal = one node, one conceptDistributed = concepts distributed across multiple nodesPage 2ArchitectureInputOutputHiddenThese models are frequently called Parallel Distributed Processing (or PDP) modelsAdvantages1) Graceful degradation2) Also seeks to show how memories are acquired, not just how they are organized after learning.3) Automatically finds prototypes and exceptions to prototypes4) Automatically generalizesCriticisms of PDP1. Catastrophic interference2. Ability to learn rulesIs that everything in memory?Until 20 years ago, the answer would have been “yes.”Today, most memory researchers believe that there are a number of memory systems, at least five of them. Patient HM• Retrieval from LTM intact• STM intact• Ability to get material from STM to LTM (i.e. ability to learn) devastatedAmnesiaRetrograde:• Loss of memories encoded before insult to brain • Usually traumatic brain injuryAnterograde:• Loss of memories encoded after an insult to the brain• Usually result of stroke or diseasePage 3ConsolidationThe process by which memories become more stablePursuit rotor, mirror tracingHM is shown to learn a new motor skills.More amnesics tested, more tasks learnedPage 4Conclusion from this work:It’s not just that there is memory and there are motor skills: perceptual stuff can be preserved.Amnesic patients seemed to show good retention for material with certain testing methods.Page 5Amnesics could learn other tasksClassically conditioned responseMirror-reversed readingMultiple memory systemsMultiple systems of memory could account for dissociation between poor and intact tasks in amnesiaProcedural vs. DeclarativeProcedural memory:• memory for skills; “knowing how”Declarative memory: • memory for facts and events, “knowing what”Memory systemsDeclarative memory--recall, recognitionRepetition priming—e.g. pictures taskMotor skill learning--e.g. pursuit rotorClassical conditioning--e.g., eyeblinkEmotional conditioning--emotional response to previously neutral stimulusDeclarative memoryRepetition PrimingMotor skill learningEmotional conditioningClassical conditioninghippocampusDeclarative memoryRepetition PrimingMotor skill learningEmotional conditioningClassical conditioningVisual cortexPage 6Declarative memoryRepetition PrimingMotor skill learningEmotional conditioningClassical conditioningBasal gangliaDeclarative memoryRepetition PrimingMotor skill learningEmotional conditioningClassical conditioningAmygdalaDeclarative memoryRepetition PrimingMotor skill learningEmotional conditioningClassical conditioningCerebellumAwarenessDeclarative memory is associated with awarenessOther learning is not necessarily.Episodic vs. SemanticEpisodic memory• associated with a specific time and placeSemantic memory• knowledge of what things are: factsMultiple memory systemsThis research has expanded our notion of memory. There appear to be multiple cognitive systems in the brain that have some