MemoryMemory

Modal Model of the MindModal Model of the Mind

Three memory storesThree memory stores Four Control ProcessesFour Control Processes

Long-term memory

Working orShort-term

Memory

Sensory

Input

Sensory Memory

Attention Encoding

Retrieval

Maintenance Rehearsal

Sensory Memory StoreSensory Memory Store

Divided into two Divided into two subtypes:subtypes: iconic memory - visual iconic memory - visual

informationinformationechoic memory - echoic memory -

auditory informationauditory information Visual or iconic memory Visual or iconic memory

was discovered by was discovered by Sperling in 1960 Sperling in 1960

Sensory

InputSensory Memory

Sperling’s ExperimentSperling’s Experiment

Presented matrix of letters Presented matrix of letters for 1/20 a secondfor 1/20 a second

Report as many letters as Report as many letters as possiblepossible

Subjects recall only half of Subjects recall only half of the lettersthe letters

Was this because subjects Was this because subjects didn’t have enough time to didn’t have enough time to view entire matrix? Noview entire matrix? No

How did Sperling know this?How did Sperling know this?

Sperling’s ExperimentSperling’s Experiment

Sperling showed people can see Sperling showed people can see and recall ALL the letters and recall ALL the letters momentarilymomentarily

Sounded low, medium or high tone Sounded low, medium or high tone immediately after matrix immediately after matrix disappeareddisappeared tone signaled 1 row to reporttone signaled 1 row to report recall was almost perfectrecall was almost perfect

High

Medium

Low

Memory for image fades after 1/3 seconds or so, making report of entire display hard to do

How does Information get How does Information get from Sensory to STM?from Sensory to STM?

Who did research in this Who did research in this area?area?

Selective AttentionSelective Attention

Also called “Preattentive Processing”Also called “Preattentive Processing”

Cherry 1953Cherry 1953

Dichotic ListeningDichotic Listening

Cocktail Party EffectCocktail Party Effect The ability to focus on a single speaker, even if The ability to focus on a single speaker, even if

there are many speakers, is known as the there are many speakers, is known as the “cocktail party effect”“cocktail party effect”

The hearing impaired have a diminished ability The hearing impaired have a diminished ability to focus on one speaker when there are to focus on one speaker when there are numerous contemporaneous soundsnumerous contemporaneous sounds

Recent research aims to separate the audio Recent research aims to separate the audio signals so that only the speaker of interest is signals so that only the speaker of interest is amplified by the hearing aidamplified by the hearing aid

Separation MethodsSeparation Methods Classical methodsClassical methods

Exploit spectral diversityExploit spectral diversity BeamformingBeamforming

Assumes speech sources of no interest are in far fieldAssumes speech sources of no interest are in far field Adaptive Noise CancellationAdaptive Noise Cancellation

Assumes availability of reference signalAssumes availability of reference signal (which must not (which must not contain speech of interest)contain speech of interest)

Blind Source Separation, BSSBlind Source Separation, BSS Exploit spatial diversity, e.g., speech sources must be Exploit spatial diversity, e.g., speech sources must be

spatially distinctspatially distinct

Short Term Memory StoreShort Term Memory Store

Function - conscious processing of informationFunction - conscious processing of informationwhere information is actively worked onwhere information is actively worked on

Capacity - limited (holds 7 +/- 2 items) Capacity - limited (holds 7 +/- 2 items) Duration - brief storage (about 15 - 30 seconds)Duration - brief storage (about 15 - 30 seconds)

Working orShort-term

Memory

Sensory

Input

Sensory Memory

Attention

Short Term MemoryShort Term Memory

Miller – The Magical Number 7, Plus or Miller – The Magical Number 7, Plus or Minus Two.Minus Two.ChunkingChunking

Peterson and Peterson – Short Term Peterson and Peterson – Short Term Retention of Individual Verbal Items.Retention of Individual Verbal Items.

Maintenance Rehearsal Maintenance Rehearsal

Working orShort-term

Memory

Sensory

Input

Sensory Memory

Attention

Allows information to remain in working memory longer than the usual 30 seconds

Maintenance rehearsal

Working Memory ModelWorking Memory Model

Baddeley (1992)Baddeley (1992)3 interacting components3 interacting components

Central Executive

Phonological Loop

Visuospatial Sketch Pad

Working Memory ModelWorking Memory Model

Visuospatial sketch pad - holds visual and spatial infoVisuospatial sketch pad - holds visual and spatial info Phonological loop - holds verbal informationPhonological loop - holds verbal information Central executive - coordinates all activities of working Central executive - coordinates all activities of working

memory; brings new information into working memory from memory; brings new information into working memory from sensory and long-term memorysensory and long-term memory

Central Executive

Phonological Loop

Visuospatial Sketch pad

How does Information get How does Information get from STM to LTM?from STM to LTM?

Who did research in this Who did research in this area?area?

Encoding andEncoding andLevels of ProcessingLevels of Processing

Craik and Tulving 1975Craik and Tulving 1975

Typ

e of

P

roce

ssin

g

Shallow -Acoustic

Deep

Shallow - Visual

10 20 30 40 50 60 70 80 90 1000Percent of words recalled

Positive correlation between grades and Positive correlation between grades and use of elaboration in 5th grade studentsuse of elaboration in 5th grade students

In an experiment, college students In an experiment, college students assigned to use elaboration received assigned to use elaboration received higher grades than students not taught higher grades than students not taught elaboration elaboration

More Evidence for ElaborationMore Evidence for Elaboration

Ways to Use ElaborationWays to Use Elaboration

Actively question new informationActively question new informationThink about its implicationsThink about its implicationsRelate information to things you already Relate information to things you already

knowknowGenerate own examples of conceptsGenerate own examples of conceptsDon’t highlight passage as you readDon’t highlight passage as you readFocus on the ideas in the textFocus on the ideas in the text

EpisodicMem ory

Sem anticMem ory

E xp lic it M em ory

P roceduralMem ory

C lassicalConditioning

Prim ing

Im p lic it M em ory

Long-term M em ory

Long-term Memory SystemsLong-term Memory SystemsSquire 1993Squire 1993

Explicit MemoryExplicit Memory

Also known as declarative or conscious memoryAlso known as declarative or conscious memory

Episod ic M em ory Sem antic M em ory

Explic it M em ory

Implicit MemoryImplicit Memory

Also known as nondeclarative memoryAlso known as nondeclarative memoryInfluences your thoughts or behavior, Influences your thoughts or behavior,

but does not enter consciousnessbut does not enter consciousness

C lassica lC ond ition ing

Procedura lM em ory

Prim ing

Im p lic it M em ory

There is biological evidence for these There is biological evidence for these theories as shown in Pet Scans.theories as shown in Pet Scans.

Modal Model of the MindModal Model of the Mind

Three memory storesThree memory stores Four Control ProcessesFour Control Processes

Long-term memory

Working orShort-term

Memory

Sensory

Input

Sensory Memory

Attention Encoding

Retrieval

Maintenance Rehearsal

Elizabeth Loftus and Elizabeth Loftus and John Palmer: Memory John Palmer: Memory

Experiment and HypothesisExperiment and Hypothesis

Hypothesis: People will remember a car accident Hypothesis: People will remember a car accident differently if given different language cues (words) differently if given different language cues (words) about the accidentabout the accident

Loftus and Palmer: Loftus and Palmer: MethodologyMethodology

Students watched a film of two cars collidingStudents watched a film of two cars colliding Collision was moderate with no broken glassCollision was moderate with no broken glass Different students asked different questions: hit, Different students asked different questions: hit,

smashed, collided, bumped, contacted smashed, collided, bumped, contacted

Loftus and Palmer: ResultsLoftus and Palmer: Results

People reported the fastest speeds if the researchers People reported the fastest speeds if the researchers had used the word “smashed” in the questionhad used the word “smashed” in the question

From fastest to slowest reported speeds: smashed, From fastest to slowest reported speeds: smashed, collided, bumped, hit, and contacted groupscollided, bumped, hit, and contacted groups

VERBVERB MEAN ESTIMATE OF SPEED (MPH)MEAN ESTIMATE OF SPEED (MPH)

SmashedSmashed 40.840.8

CollidedCollided 39.339.3

BumpedBumped 38.138.1

HitHit 34.034.0

ContactedContacted 31.831.8

Loftus and Palmer: ResultsLoftus and Palmer: Results

One week later, subjects were asked if they had seen One week later, subjects were asked if they had seen broken glassbroken glass

32% of subjects asked the “smashed” question said 32% of subjects asked the “smashed” question said yes; 14% of subjects asked the “hit” question said yesyes; 14% of subjects asked the “hit” question said yes

Loftus and Palmer: Results Loftus and Palmer: Results and Implicationsand Implications

People remember things differently depending on the People remember things differently depending on the language used to describe an event (e.g., “smashed” language used to describe an event (e.g., “smashed” versus “hit”)versus “hit”)

Misinformation effectMisinformation effect

Role of Time : Decay TheoryRole of Time : Decay Theory

Memories fade away or Memories fade away or decay gradually if unuseddecay gradually if unused

Time plays critical role Time plays critical role Ability to retrieve info Ability to retrieve info

declines with time after declines with time after original encodingoriginal encoding

Problem: Many things Problem: Many things change with time. change with time. Something else may Something else may change and actually cause change and actually cause forgetting: Interferenceforgetting: Interference