1.107 Memory and Dysfunction Flashcards
What is declarative memory?
Records of facts and events
Accessible to consciousness
What is procedural (implicit) memory?
• Skills and behaviours.
○ How to play the piano, ride your bike, text a message …
• Involves learning a motor response in association with a sensory input.
Inaccessible to consciousness, and hard to forget.
Which parts of the brain does implicit memory involve?
Stiatum - skills and habits
Skeletal musculature - cerebellum
Emotional responses - Amygdala Associative learning
Where are memories stored?
Memories are distributed throughout neocortex, BUT rely on a different memory circuit depending on whether they are declarative or procedural.
If based on information from one sense only, they are located in cortical regions that serve this sense
What does DNMS depend on?
Performance on DNMS (delayed non match to sample task) task, critically depends on entorhinal cortex in medial temporal lobe.
What is the role of the hippocampus?
Spatial memory
-hippocampal cells have place cells
Associative learning
What does a lesion in the entorhinal cortex result in?
MEDIAL TEMPORAL LOBE
Declarative memory and not procedural affected
Anterograde amnesia
Long term memory more severely affected than short term
What is the pathway for long term memory formation?
Cortical association areas - Parrahippocampal and rhinal cortex - Hippocampus - fornix - thalamus, hypothalamus - Prefrontal cortex - neocortex
What is Kluver-Bucy syndrome?
Frontotemporal dementia
What does a medial temporal lesion in the amygdala cause?
Kluver-Bucy syndrome - visual agnosia, emotional changes, hyperphagia, hypersexuality, emotional memory impairments and disturbances
What are the symptoms of Korsakoff’s syndrome?
Anterograde and retrograde amnesia
Thiamin deficiency due to chronic alcoholism
Thalamus memory affected (diencephalon)
Lesion in mammillary bodies, thalamus, and elsewhere
What does a striatal lesion cause?
Cannot associate a sensory stimulus with a motor response
Parkinson’s - substantia nigra - input to striatum - cannot form stimulus-response habits- good declarative memory
What are primary dementias?
Proteins deposit problems cause neuronal death - Alzeihmers - plaques and tangles
Dementia with Lewy Bodies - Ubiquitin positive cortical neurones
Pick’s disease - frontotemporal degeneration
What is secondary dementia?
Associated with systematic or neuronal disease
What is Alzeihmer’s?
Degeneration of temporal lobe
Neurofirbillary plaques and tangles
Seen first in rhinal cortex
Also in hippocampus, amygdala and anterior thalamus
