brain and behavior learning and memory lecture

learning

the process of aquiring new information. if we test something is learned by determining if there is information or ability gained over time, memory.

memory

the ability to story and retrieve information and the specific information stored in the brain.

brain damage

it often impairs both leaning and memory.

declarative memory

facts and information acquired through learning that can be stated or described; used to ask to “what?” questions. knowing 50 states and describing your 8th birthday. hard to test in non-humans

nondeclarative (procedural) memory

shown by performance rather than recollection; used to answer the “how?” questions. tying your shoelaces. can be tested in all species using mirror reading/tracing and motor skills

retrograde amnesia

the loss of memories formed before onset of amnesia. it is the most common type of memory loss. It can result from brain injury or trauma and affects a person's ability to recall past events ( 1 hour, 1 day, or up to 1 year)

anterograde amnesia

the inability to form certain types of new memories after onset of a disorder. the patients cannot form new episodic memories. they can learn to read mirror -reversed text. they can learn through verbal memory. the patients can also learn new motor skills through procedural memory.

patient H.M

old memories were intact and his short term memory and procedural memory were intact. he could not remember anything after his surgery or retain any new material long term.

what we learned from HM case

it supported the behavioral evidence that there are different kinds of memory and that different types of memory are served by different parts of the brain.

HMs surgery

they removed the amygdala, the hippocampus, and adjacent medial temporal cortex bc he was suffering from severe epileptic seizures. this led to his cerebellum shrinking due to a lack of hippocampal connections.

what therapy was used to improve his procedural memory?

mirror therapy. he improved how to read mirror-reversed text - a verbal memory skill. it showed that the deficit was not simply a verbal memory deficit

delayed non-matching-to-sample task

a test of object recognition memory that requires monkeys to declare what they remember.

what impairs delayed non-matching-to-sample task

medial temporal lobe

what have we learned about the hippocampus in memory?

at lease hippocampus is necessary for new declarative memory formation but the hippocampus is not sufficient—because surrounding cortical areas are needed as well.

patient N.A

had a miniature sword pierce his brain through his nostril. there was no damage to the hippocampus but significant damage to dorsomedial thalamus and mammillary bodies. has short term and procedural memory but no declarative long-term memories.

korsakoffs syndrom

a memory deficiency caused by lack of thiamine. its mainly seen in chronic alcoholism with abnormal food intake. a treatment with thiamine can prevent future memory loss. there is damage occuring in mammillary bodies and dorsomedial thalamus, but not the hippocampus.

confabulate

filling in memory with a falsification and do not acknowledge their problem. this is unique to korsakoffs due to damage in the frontal cortex.

what is necessary to form new memories?

hippocampus and adjacent cortices. dorsomedial thalamus and mammillary bodies.

semantic memory

generalized declarative memory such as knowing facts like the table of elements.

episodic memory

detailed autobiographical memory such as remembering when and where you learned the table of elements.

patient K.C

had damage to his left-fronto-parietal and right parieto-occipital cortices and had a severe shinkage to hippocampi and adjacent tissue due to the reduced connections. he can no longer make new episodic memories and learn new facts but no memory of learning them.

what do we learn from K.C hippocampal damage?

its responsible for his anterograde amnesia. however, hippocampus cannot account for loss of auto biographical memory. its likely from damage to the frontal and parietal cortices.

declarative memory

hippocampus and adjacent cortices. dorsomedial thalamus and mammillary bodies. these are necessary. the memories are liekly distributed across cortex. episodic specific to ones life may be stored in frontal and parietal cortices.

what is the role of medial temporal structures?

to bind or gather encoded information from other parts of the brain.

procedural memory

its skill learning and the different ones are sensorimotor (mirror tracing), perceptual (mirror reading), cognitive (tower of hanoi-problem solving). all are impaired with damage to the basal ganglia.

priming

a change in stimulus processing due to prior exposure to the same or related stimulus. this is a fuction of the cortex

associative learning

qa learning process where an association is made between a stimulus and a response. It involves linking one stimulus with another through experience.

classical conditioning (palvonian conditioning)

a neutral stimulus, when paired with another stimulus that elcits a respins, is able to elicit that same response when presented alone.

conditioned eye blink

its lost with damage to the cerebellum

meat powder in pavlon test

uncondtiioned stimulus (US) that evokes an unconditioned response (UR), salvation

bell sound in pavlovs test

the conditioned stimulus (CS) and the learned response to the CS alone, salivation, is the response to conditioned response (CR)

operant conditioning

an association between behavior and consequence of the behavior (reward/punishment)

reinforment learning

addictive behavior (dopamine)

negative reinforment

learned helplessness (seratonin)

reward learning in humans

praise stickers, allowance, gambling (addiction), drugs (addiction)

punishment

add a negative stimulus, remove a positive stimulus (privilage)

cognitive map

a mental representation of a spatial relationship, which the hippocampus is important for.

hippocampal place cell

they become active when in or moving toward a particular location like orientation specific and object specific.

what lesion produces a deficit in spatial task

hippocampus lesions.

what lesions affect motor behavior

basal ganglia lesions.

what lesions affect sensory perception?

cortical lesions

stages of memory in time

iconic/echoic memories → short-term memories (STMs) → long-term memories (LTMs).

iconic/echoic memories

briefest sensory impressions; seconds

short-term memories (STMs)

30 seconds without rehearsal; until next task if rehearsed. its also called working memory

long-term memories (LTMs)

lasts for days to years

3 stages of processing

encoding, consolidation, and retrieval

encoding

sensory information is encoded into short-term memory; sensory to STM

consolidation

information may be consolidated into long-term storage; STM to LTM

retrieval

stored information is retrieved from LTM

classical model of long term memory

incoming information → iconic memory → encoding → short them memory → consolidation → long term memory → retrieval → short term memory

what was the issue for henry molaison and clive wearing?

they had a damaged or missing hippocampi . they could maintain brief conversations but would forget things within seconds to minutes.

why do we think STM and LTM are different?

STM can be encoded and retrieved but at least one intact hippocampis is required to consolidate declaritve STMs into LTMs. STMs may be more vulnerable to trauma and more likely to be lost than LTMs.

U-shaped serial position curve

it includes primacy effect and recency effect

primacy effect

higher performance for items at the beginning of a list (LTM)

recency effect

better performance for items at the end of a list (STM). HM had recency

immediate tests

recency effect but no primacy effect

tests after short delay

both recency and primacy effects

tests after longer delay

primacy effect but no recency effect

memory trace

the record laid down by an experience doesn’t just deteriorate over time, but is interfered with by other events occurring before or after.

memories are reconstructed

the process of retrieving information from LTM can cause memories to become unstable and susceptible to disruption or alteration

reconsolidation

the return of a memory trace to stable long term storage, after recall.

episodic memory

high emotional value have especially strong connections

odors with memory

powerfull at triggering memories, especially episodic

emotionally charged memories

the release of epinephrine (adrenaline) from adrenal glands in large quantities. it enhances the response of the amygdala (PTSD). treatment with beta blockers can lessen the impact of traumatic experience on memory.