quiz 2 - working memory

memory

collection of processes involved in retaining, retrieving, and using information about stimuli, images, events, ideas, and skills after the original information is no longer present

modal model of memory

• computer as model for human cog

• integrated system that processes info

• limited capacity

atkinson and shriffin model of memory flow

input → sensory memory → short-term memory (→ output) or → ←long term memory

control processes

active processes that can be controlled by the person

• rehersal, strategies to make more memorable, strats for attention

persistence of vision

retention of the perception of light

sensory memory

holds large amount of information for a short period of time

• collects info, holds info for processing, fills in the blanks

what happens in short-lived sensory memory when info hits our visual receptors?

registers all or most information; info decays very quickly

sperling, 1960 (modal model of memory; sensory memory) → whole, partial, and delayed partial report

• measuring capacity and duration of iconic memory

• whole report: array of letters flashed on screen and participants asked to report as many as could be seen (37.5%)

• partial report: participants heard a tone that told them which row to report (82.5%); could report any row

• delayed partial report: presentation of tone delayed for a fraction of a second after letters were extinguised (performance decreases rapidly)

short-term memory

stores small amounts of info for a brief duration (limited in time); includes info from sensory stores and info recaled from long-term

proactive interference

occurs when info learned previously interferes with new info; responsible for short-term memory quick decay

chunking

small units can be combined into larger meaningful units (items are strongly associated with each other)

coding

the way information is represented

physiological coding

how stimulus is represented by the firing of neurons

mental coding

how stimulus or experience is represented in the mind

auditory coding (conrad, 1964)

• participants saw letters and wrote them down after a short delay

• errors occured when letters sounded alike

• STM is auditory

visual coding (sala, 1999)

• presented visual info that is difficult to verbalize

• participants could recreate patterns of up to 9 items

• STM is visual

semantic coding (wickens, 1976)

• participants listened to 3 words, counted backwards for 15 s, and attemted to recall

• 4 trials, different words

• trial 4: participants memorized words from different category

  • meanings of words used in processing

• STM is semantic

working memory

limited capacity system for temporary storage and manipulation of info for complex tasks such as comprehension, learning, and reasoning

how do working memory and short-term memory differ?

• STM: single component

• WM: consists of multiple parts

• STM: holds info for a brief period of time

• WM: concerned with processing and manipulation of info during complex cognition

phonological loop

composed of two sub-systems

• phonological memory source: holds traces of acoustic or speech-based material with limited time capacity

• articulatory sub-vocal rehersal: maintains phonological memory traces, translates visual info by sub-vocal naming

auditory (phonological) input

• info: sensory memory → central executive → phonological memory store

• capacity: 2 seconds

• trace kept active using articulatory sub-vocal rehearsal unit

• if not refreshed, decay

visual/visuospatial input

• info: sensory memory → central executive → visuospatial sketchpad

• if verbal-based: transfer to articulatory sub-vocal rehearsal unit for sub-vocal naming or translation

• transferred to phonological memory store

phonological similarity effect

• results: support auditory coding and translation in working memory

• in auditory condition and visual condition: 95% errors due to auditory similarity

Baddeley, Thomson & Buchanan (1975): word length

• goal: show that immediate memory span for verbal info is not constant, but varies with length of words recalled

• must recall entire sequence to be correct

• clear advantage for short words over long

• temporal duration, not meaningful units

Baddeley, Thomson & Buchanan (1975): articulatory suppression

• goals: show that articulatory sub-vocal rehearsal component maintains memory traces and translates visual info in phonologicalmode

• serial recall with varying word length, type of presentation, and possibility of rehearsal

• word length matters in both presentation modes

• support for translation from visual to phonological

• translation maintains visual vinfo with phonological aspect

visuospatial sketch pad (brooks, 1968)

• memorize sentence and then consider each word

• response is to either say “yes or no” or point to Y or N

• pointing was easier than speaking

• conducting two verbal tasks overloads phonological loop

• conducting two visuospatial tasks overloads sketch pad

central executive

• component of working memory

• attention controller: focus, divide, switch attention

• controls suppression of irrelevant info

• manipulates info

prefrontal cortex and WM

responsible for integrating and processing incoming visual and auditory information

• monkeys without this have difficulty holding info in WM

WM and the brain

• areas in frontal lobe and parietal lobe are involved

• neurons respond when stimulus was flashed in particular location and during delay

• info remains available via these neurons for as long as they continue firing