Memory Disorders

Psychology 3717

Introduction

• The strange case of Charles D’Sousa

• Or is it Philip Cutajar?• Rare type of disorder• Some stuff clearly

spared

Introduction

• Results with amnesiacs has lead to many discoveries about memory– Episodic vs. semantic memory– Procedural vs. declarative memory– Implicit vs. explicit memory– Phonological loop vs. visuo spatial sketchpad

problems

• Taxonomy• Individual differences• Interpretation• Application• Mostly comes down to a lack of control, which

of course is inevitable

Case studies

• We pretty much have to rely on these• They are, thankfully, rare• Usually some sort of accident or a stroke

Case SP

• Stroke patient• Both Medial temporal lobes, left Hp and lots

of surrounding area, but not the amygdala• Had trouble naming objects• Anterograde and retrograde amnesia• Similar to KC

Clive Wearing

• Case of encephalitis• Pervasive amnesia• Both semantic and

episodic impairment• Temporal lobe dilation• Hp destroyed

Performance Patterns

• Retrograde amnesia– Losing past memories

• Anterograde amnesia– No new memories

• Spared function– Often implicit tasks, such as priming or ability to

learn a new skill

Typically spared

• Working Memory• Semantic memory – Even KC could learn new stuff

• Declarative information using Tulving’s method– Restrict errors

Why?

• Difficulties in interference, retrieval and encoding

• Consolidation– Tends to come down to something to do with HP– Context or sending item off for processing or

some such thing

Semantic memory problems

• What is a cat?• Temporal lobe problems• Oddly enough, episodic memory often intact

in these rare cases

Working Memory Problems

• There are cases of people with intact phonological loops and visuo spatial sketchpads that are pretty much toast

• And vice versa

Alzheimer’s

• More than half of all dementia is from AD

• 2 times more women than men– Could be because

women live longer though

• dementia and brain stuff– Neurofibrillary tangles

and neuritic plaques

AD

• MASSIVE cell death• In essence, you get like lesions everywhere• ‘cortical’ dementia, but you get these lesions,

holes really, everywhere

Neurotransmitters affected

• ACh is important in memory, especially in HP• The ACh system is severely damaged in AD• Indeed it is almost targeted• Other systems too though

Memory effects

• Episodic effects• Eventually semantic effects• Retrieval cues don’t help– Information was not even encoded

• Nondeclarative stuff, skills etc, are the last to go

Treatment

• Most drugs target the cholinergic system• This disease not only affects the victim, but

also his/her family• NGF is promising• Treatments will come, but, reversal, I dunno• Respite care is key for the family

Conclusions

• Frankly there is not a great deal of hope for most amnesiacs

• That said, neuroscience is moving pretty fast• Has helped us understand normal function