Memory

Memory

1. AMNESIA

   • PSYCHOLOGICAL
     • 1.Organic amnesia - head trauma
     • 2.Infantile amnesia - forgetting childhood
     • 3. Repression amnesia - forgetting events you repressed
   • Causes of Amnesia- stroke, head injury, herpes, anoxia (no oxygen to the brain) and korsokoffs syndrome (alcohol abuse)
     • Brain Areas Korsokoffs affects - subcortical Anoxia affects - Cortical
   • EXAMPLE - HMs epilepsy cured when temporal lobes were removed
     • Mostly HMs hippocampus and Amygdyla removed = he had anterograde amnesia
       • 5. Anterograde amnesia - loss of mem after trauma
         • TEMPORAL
           • 4. Retrograde amnesia - forgetting what happened before trauma
   • Amnesiacs good at IMPLICIT/NON-DECLARITIVE - skill learning, priming (memory triggered by cues)
     • 3. Mann et al - amnesias impaired in recalling words (verbal) and faces (visual)
     • 1. Reed & Squire - amnesiacs only remembered famous names (out of new vocab, pulic events & famous names) =evidence of priming
     • 2. Schater, 1987 - also found amnesiacs better at implicit than explicit tests
     • EVIDENCE FOR
     • 1. Koppelman & Stanhope, 1998 - amnesias performed the same as controls
     • 2. Schater et al, 1995 - amnesias had impaired implicit
     • 3. Aggleton & Brown, 1999 - these studies FOR, 'lump' all amnesias together...theres different types
     • EVIDENCE AGAINST
   • Developmental Amnesia - Jon, 34, was born prematurely with 50% reduced hippocampus. He forgets everyday objects
     • Enactment Effect, Englekamp, 1998 - read vs. read and perform
       • READ UP ON THIS!
   • Aggleton & Brown - Two distinct Memory Systems
     • Hippocampus system (remember) Perirhinal system (know)
       • Patient QX - damage to left dorsomedial (in perirhinal) which impaired his anterograde mem and executive functions (dual tasks, planning/organising)
         • Testing the memory systems - QX had 50 words to learn then showed 50 new words. Had to say whether he remembered or knew
           • Predicted QX could recall but wouldnt be familiar
           • BUT he couldn't recall but was familiar
             • The two system theory was incorrect

2. Everyday Memory

3. Biology of Memory

   • Overview of memory
     • Multi-store model ATKINSON & SHIFFRIN 1968
       • INPUT
         • Sensory Store
           • Short term store
             • Long term store
               • OUTPUT
               • Rehearsal into Permanent Memory Store
             • Rehearsal, Coding, Decisions and Retrieval
           • Iconic and Echoic
             • EVIDENCE FOR - Iconic (delayed cues impair) Echoic (suffix effect impairs auditory memory) - Sperling, 1960
       • EVIDENCE
         • SHORT TERM - Chunking, 7 Digit Span - Miller, 1957
           • Needs Rehearsal - Murdock, 1961
         • LONG TERM - Primary Recency Effect - Grazner and Kunitz, 1966
     • Working Memory Model BADDELEY & HITCH, 1974
       • Visuo-Spatial Sketch Pad VSS
         • Central Executive CE
           • Phonological Loop PL
             • Stores for 1-2 sec > transfers visual info to speech
               • PL EVIDENCE - Word length effect - remember shorter words (to say out loud) Baddeley et al
           • Planning/Organising; dual-tasks; selective attention
             • CE EVIDENCE - Stroop effect (Kahnmen & Henik)
         • VISUAL CACHE; form + colour INNER SCRIBE; Movement/Spatial.Transfers info to CE
           • VSS EVIDENCE - spatial task activates right; visual task activates left - (Smith & Jonides)
       • Episodic Buffer - Baddeley added this later for general storage - integrates range of info into one episode w.g. driving
     • Long Term Memory - SQUIRE, 1992
       • Declaritive - Explicit (Conscious)
         • Episodic - events, birthdays, episodes that happened last week
         • Semantic - Knowledge of words/meanings
         • EVIDENCE - Elaborative Processing - Likability Rating (Gratzner & Madler)
       • Non-Declaritive - Implicit (Unconscious)
         • Skill Learning, Driving, Swimming, Walking
         • Priming - Memory prompted by cues
         • Conditioning - memory prompted by behaviour (dog salivating)
         • EVIDENCE - Shallow Processing - Letter spotting (Gratzner & Mandler)
     • SUMMARY - WMM better that MMM - explains partial deficits (one segment can be damaged) however limits of CE not known
   • NEURONS AND SYNAPSES
     • Neuron transmits/processes info; Synapse - area where communication occurs; Neurotransmitter - substance that communicates 1-2-1 with two neurons
       • Neurons learn by repeated occurence then synapse gets strengthened = structural changes. The changes increase transmission of learning = learning
         • Hebb Synapse - Hebb, 1949
           • Hebb Synapse (increased learning) leads to long-term potentiation (change) (LTP)
             • Behaviourally (rats condittioned to get out of murky water)
             • Neurophysiologically - synapses become sensitive/change in reactivity of postsynaptic neuron
             • LTP in hippocampus; NMDA receptors in hippocampus represent biological basis of long-term memory
         • Structural Changes
           • Habituation - decline in response to stimulus repeatedly presented
           • Sensitisation - system responds more strongly to a stimulus because its noxious (harmful)
           • Aplysia Snail - Habituation (when touched, gill withdraws but soon stops), Sensititation (pinch tail, rapid withdrawl gets stronger)
             • Kandel, 1991