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