Learning and Memory
Memory is a multi-staged process with 4 distinct levels:
Immediate Memory– 100ms-seconds
Short Term Memory– seconds to minutes
Intermediate Memory– minutes to hours
Long Term Memory– days/weeks/lifetime
Working memory refers to capacity to hold information in order to conduct sequential actions. Multiple sensation modalities.
Declarative memory is a “knowing that” response which involves a conscious collection of facts and events expressed by language. Uses HIPPOCAMPUS, mid-temporal lobe, diencephelon.
Procedural memory is unconscious memory which refers to collections of abilities for habitual actions. Priming effects, acquisition of motor skills. Uses striatum, neocortex, amygdala, cerebellum.
Retrograde amnesia is the length of the period for a given memory impairment. Graded such that severity of amnesia is inversely proportional to the age of the memory at the time of injury. Material in memory becomes resistant to disruption with time, but also more difficult to recall.
Anterograde amnesia is the inability to from new memories after a specific time/event. There is an inability to convert SHORT term memories to long term memories. Occurred in patient HM due to resection of the temporal lobe bilaterally, hippocampus and uncus.
Stroke, or cerebral ischemic events, cause memory loss due to decreased blood to limbic structures. Loss of CA1 cells of hippocampus.
Cued response greatly assists amnestics in recalling memories.
Serial position effect is the ability to recall memories which are at the BEGINNING and END of a list of information. Primary effect– better memory of first set of data due to protection from interference and rehearsal. Recency effect– better memory of last set of data due to short term memory. Amnestics– normal Recency, impaired Primacy.
Tags: Amnestics, Anterograde amnesia, cerebral ischemic, Declarative memory, Immediate Memory, Intermediate Memory, Long Term Memory, Procedural memory, Retrograde amnesia, Short Term Memory, stroke
