Chapter 13: Memory Phases - Working & Short Term Memory

Question 1

What is the mechanism of short term (working) memory?

Answer 1

maintenance of activity (reverberation; through rehearsal) & short to intermediate term activity of dependent synaptic change (LTP)

Question 2

What are the structures involved in short term (working) memory?

Answer 2

prefrontal cortex
parahippocampal cortices

Question 3

What is the mechanism of long term memory?

Answer 3

maintained synaptic changes (L-LTP)

protein synthesis

anatomical growth

Question 4

What are the structures involved in long term memory?

Answer 4

hippocampus

Question 5

What is the model of memory processes?

Answer 5

serially related memory stores that differ in function, capacity, and duration

control processes - control movement of information within and between memory stores

Question 6

What is the function of sensory memory?

Answer 6

holds information long enough to be processed for basic physical characteristics

need to be able to perceive sensory information in order to make connections

Question 7

What is the capacity of sensory memory?

Answer 7

large

can hold many (infinite) items at once

Question 8

What is the duration of sensory memory?

Answer 8

very brief

0.3 sec for visual info
2-5 sec for auditory info

Question 9

In what way is sensory preattentive?

Answer 9

forms without attention

don’t need to be actively paying attention

Question 10

What are the two types of sensory memory?

Answer 10

based on modality

iconic: visual
echoic: auditory

Question 11

Why is attention important to working memory?

Answer 11

sensory memory forms automatically, without attention or interpretation

attention is needed to transfer information to working memory (consciousness)

Question 12

What is the function of working memory?

Answer 12

conscious processing of information

where information is actively worked on

Question 13

What is the capacity of working memory?

Answer 13

limited (holds 7 +/- 2 items)

Question 14

What is the duration of working memory?

Answer 14

brief storage (about 30 seconds)

however, can be elongated through rehearsal

can be maintained for a long period of time, but requires active attention

Question 15

What is encoding?

Answer 15

once in working memory, information can be transferred into long-term memory

Question 16

What is retrieval?

Answer 16

once stored in long-term memory, information can be transferred from back in to STM

Question 17

What is the function of long term memory?

Answer 17

organizes and stores information

organized in a way that helps you retrieve it through association

more active form of encoding than working memory

more passive form of storage than working memory

Question 18

What is the capacity of long term memory?

Answer 18

unlimited

Question 19

What is the duration of long term memory?

Answer 19

relatively long term (hours to months)

however, still labile, not permanent; can forget details

Question 20

What is ultra long-term memory?

Answer 20

to achieve permanence, memories must be consolidated into ultra-long term memory

retrieval to STM can also occur from this store

return to lability and reconsolidation (through LTM)

Question 21

What are the characteristics of short term (working) memory?

Answer 21

conscious representation (short term from of declarative memory)

flexible and permanent

stream of information; new (sensory inputs) and old (retrieval from LTM)

manipulations, associations, reasoning

intact in amnesics: HM, EP, RB

Clive Wearing: showed very limited amount, limited window of consciousness, damage just above temporal lobe in prefrontal region

Question 22

What is the cognitive psychology (Baddeley) model for short term memory?

Answer 22

specialized subsystems interacting with a “central executive”: phonological loop and visuospatial sketch pad

lack of interference between these different modalities

Question 23

What are the characteristics of the prefrontal cortex that make it the central executive for short term memory?

Answer 23

integrates sensory modalities; especially vision and audition

interfaces sensory and motor systems; organizes behavior

has access to declarative memory structures: retrieval from LTM, encoding into LTM?

shows short-term memory activity; able to access and retain information in the short term

Question 24

What was the 3-back task used for?

Answer 24

show how working memory activates the pFC

the tasks asks subjects to remember what happened three stimuli ago and match it

Question 25

What are the two types of 3-back tasks?

Answer 25

spatial: pay attention to spatial area of stimuli, I remember three stimuli ago there was a “G” in the corner, so a “d” in the same corner is important

verbal: paying attention to particular stimuli, I remember I was presented with a “G” three stimuli ago, so a “g” is important

Question 26

How was the activation of the pFC during working memory shown in 3-back tasks?

Answer 26

spatial: activated right dorso-lateral prefrontal cortex

verbal: activated left dorso-lateral prefrontal cortex

Question 27

What are short term memory “delay” neurons in the prefrontal cortex?

Answer 27

neurons in particular regions of the pFC “hold” representation of information regarding future responses

task: maintain fixation point then move eyes to spot where previous stimulus point

cell is active during the delay period

these cells are allowing the animal to put space into memory

Question 28

How did Phineas Gage show the non-memory functions of the prefrontal cortex?

Answer 28

behavioral inhibition versus memory

no STM deficits, personality however was completely different

Question 29

How did the Wisconsin card sorting show the non-memory functions of the prefrontal cortex?

Answer 29

cards have different color, shapes, numbers; get feedback from instructor; use that to learn what the principle of sorting is; then change the rule

frontal lesion patients will not change their first strategy, inability to look at sensory stimulus and produce accurate motor outcome

Question 30

What were the methods of the experiment determining the time-dependent interaction of pFC and HPC in memory?

Answer 30

contrast effects of drugs in different regions

cannulae: tubes that provide drugs to specific brain regions

control groups: cannulae in pFC, cannulae in HPC

experimental groups: HPC lesion/cannulae in pFC, pFC lesion/cannulae in HPC

Question 31

How was the 8-arm radial maze used in determining the time-dependent interaction of pFC and HPC in memory?

Answer 31

delayed non-matching to place

all 8 arms have reward

after rat goes down one arm, block off animal in center

after delay, block off every arm except for two; one it has gone down and one it has not

goal: go down the arm you haven’t visited

Question 32

What were the results of the experiment determining the time-dependent interaction of pFC and HPC in memory?

Answer 32

inactivate pFC: still performs the same as control, prefrontal cortex does not do anything for memory

inactivate HPC: can do task at short delays, can’t do it at long delays

in the absence of pFC, HPC does both short and long term memory

in the absence of HPC, pFC can substitute short term memory but not long term memory

HPC is necessary for long term tasks