VIII-Learning and Memory Flashcards
concept of learning
new info is acquired by nervous system to produce adaptive changes in behavior
-associative learning (passive conditioning or operant reinforcement)
-nonassociative (simple, complex imprinting)
major forms of memory
- short term - including working second/hours
- long term- hours/months
- long lasting- months/lifetime
brain regions of memory
- hippocampus
- amygdala
- temporal cortex
steps of memory processing
- sensory input acquired = short term mem
- short term mem consolidated/translocated to long term by rehearsal
- long term retrieved and recalled back to short term
physiologic mechanisms for learning
working memory
sustained/high levels of neuron firing during info holding period @prefrontal cortex
PTSD
anxiety disorder after witnessing traumatic event
-memory loss, depression, nightmare, suicide
virtual reality helps control emotions in safe environment
acquisition in associative learning
new motor behaviors
-associations b/t new stim and existing behaviors
-new associations b/t familiar stim and existing responses
acquisitions in non associative learning
- habituation - reduced respones to repeatedly exposed non noxious stim
- sensitization - inc response to repeatedly exposed stim, strong hedonic valence
concept of memory
encoding/storage/retrieval of learning info/interpreted experience
-can forget info that’s only temp useful
-context important for storage and cross referencing
features of working memory
-contents from recall of long term or recent event temporarily in mind
-guides behavior/inhibits inapprop actions
-limited capacity so easy to distract
-matures late in dev
-fragile so targeted by aging, stress
types of declarative/explicit long term
- episodic- recall events in context of time and place relative to past experience
- semantic- general knowledge of facts and concepts without reference to time and place
both brought to conscious level via hippocampus, temporal lobe, cortex
types of nondeclarative long term
- priming > neocortex
- procedural > striatum
- associative (emotional > amygdala and motor learning>cerebellum)
domains of memory
- cognitive- problem solving
- psychomotor- dance, swim, ski
- affective- like something, love, appreciate
not mutually exclusive
synaptic plasticity
mechanism of long term potentiation so enduring inc in synaptic efficacy from high freq stim of an afferent pathway
aka functional strengthening of existing synapses + formation of new synapses + activation of silent synapses
memory consolidation
newly encoded mems repeatedly reactivated during sleep to drive gradual redistribution to long term storage
-hippocampus and cortex synchronize during slow wave sleep
active forgetting
- amygdala stores fear memories
- prefrontal cortex integrates CS info with context info by hippocampus
- PFC inhibits amygdala output to reduce fear for extinction
anterograde amnesia
inability to form new memories bc defect in consolidation from hippocampus damage
-affects declarative NOT procedural mem
retrograde amnesia
inability to recall previously stored memories esp more recent memories, older ones are more resistant (temporal quality)
-memory trace still present
ex. concussion
agnosia
inability to recognize stimuli, commands
alzheimers hallmark
mem impairment with neuronal loss in hippocampus, cortex, basal forebrain (cholinergic)
-early stage anterograde amnesia > retrograde amnesia
-aphasia, apraxia, agnosia
etiology of alzheimers
neurofibrillary tangles/tau + senile plaques/beta amyloid
risk factors: age, fam hx, genes (ApoE, APP, PS1,2)
korsakoff syndrome
lack of thiamine (B1) from chronic alcoholism
-confabulation > anterograde amnesia from damage in mammillary bodies and basal frontal lobes + problems recall
treat with dietary thiamine
