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Sensory and Short-Sensory and Short-Term MemoryTerm Memory

PSY 421 – Fall 2004PSY 421 – Fall 2004

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OverviewOverview

Sensory Memory (Chapter 3, pp. Sensory Memory (Chapter 3, pp. 102-110)102-110)

Short-Term Memory (Chapter 4, pp. Short-Term Memory (Chapter 4, pp. 134-157)134-157)

How this fits together with what we How this fits together with what we have learned and what we will learnhave learned and what we will learn

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Sensory MemorySensory Memory Part of the Information-Processing Model Part of the Information-Processing Model

of Memory (Atkinson-Shiffrin, 1968)of Memory (Atkinson-Shiffrin, 1968)

Visual Sensory Memory (aka: iconic Visual Sensory Memory (aka: iconic memory)memory) Partial vs. Whole ReportPartial vs. Whole Report Visual MaskingVisual Masking Duration EstimationDuration Estimation

SensoryStores (one per modality)

Short-TermStore

Long-TermStore

Information/Stimuli

Retrieval

RehearsalAttention

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Visual Sensory/Iconic Visual Sensory/Iconic MemoryMemory

Precategorical NaturePrecategorical Nature

Iconic Memory – who cares!Iconic Memory – who cares! Useful if you are reading during a Useful if you are reading during a

lightening stormlightening storm Important for preventing overloading of Important for preventing overloading of

cognitive systemcognitive system

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Auditory Sensory Auditory Sensory MemoryMemory Echoic MemoryEchoic Memory

Everyday problem – if we didn’t have Everyday problem – if we didn’t have echoic memory, would be able to echoic memory, would be able to remember the beginning of a sentence remember the beginning of a sentence said aloud by the time we reached the said aloud by the time we reached the end?end?

Partial vs. Whole ReportPartial vs. Whole Report

Modality and Suffix EffectsModality and Suffix Effects

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Partial vs. Whole ReportPartial vs. Whole Report George Sperling (1960) – how much information could George Sperling (1960) – how much information could

be taken in during a glance of a very briefly presented be taken in during a glance of a very briefly presented stimulus?stimulus?

T-scope presentation for no-fade “screen” refreshT-scope presentation for no-fade “screen” refresh Present matrix for 50 msecPresent matrix for 50 msec Tone – subjects were to report everything in the Tone – subjects were to report everything in the

matrix (whole report) – 3 to 4 letters typically reportedmatrix (whole report) – 3 to 4 letters typically reported Partial Report = High tone – subjects were to report Partial Report = High tone – subjects were to report

top row - 3 of the 4 letters typically reported; mid and top row - 3 of the 4 letters typically reported; mid and low tones toolow tones too

Duration between presentation and tone was Duration between presentation and tone was important – more than a quarter of a second, only 50% important – more than a quarter of a second, only 50% could be reportedcould be reported

A C K LW T P ZQ R D M

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Precategorical Acoustic Precategorical Acoustic StoreStore Evidence forEvidence for

Evidence againstEvidence against

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Short-Term Memory Short-Term Memory (STM)(STM) Also known as Working Memory, primary Also known as Working Memory, primary

memorymemory Set of processes that we use to hold and Set of processes that we use to hold and

rehearse information that occupies our current rehearse information that occupies our current awarenessawareness

Is this really different from Long-Term Memory?Is this really different from Long-Term Memory?

Characteristics of STMCharacteristics of STM Limited DurationLimited Duration Limited CapacityLimited Capacity Information is coded with auditory characteristicsInformation is coded with auditory characteristics

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Forgetting in STMForgetting in STM

Decay – loss of information due to Decay – loss of information due to the passage of timethe passage of time

Interference – loss of information Interference – loss of information due to negative influence from the due to negative influence from the presentation of other informationpresentation of other information

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Working MemoryWorking Memory More elaborate conception of STMMore elaborate conception of STM Baddeley and colleagues – primary Baddeley and colleagues – primary

researchersresearchers Working Memory (WM) is a set of Working Memory (WM) is a set of

closely interacting subsystems that closely interacting subsystems that combine to subserve a hot of higher-combine to subserve a hot of higher-level mental processeslevel mental processes

SubsystemsSubsystems Articulatory LoopArticulatory Loop Visual-Spatial Sketch PadVisual-Spatial Sketch Pad

Central Executive – THE systemCentral Executive – THE system

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Articulatory LoopArticulatory Loop

Phonological Store = holds Phonological Store = holds information temporarily information temporarily

Subvocal Rehearsal = just what is Subvocal Rehearsal = just what is appears to beappears to be

Articulatory SuppressionArticulatory Suppression

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Visual-Spatial SketchpadVisual-Spatial Sketchpad

Responsible for storage and Responsible for storage and manipulation of visual and spatial manipulation of visual and spatial informationinformation

Seems to work independently from Seems to work independently from articulatory looparticulatory loop

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Central ExecutiveCentral Executive

Articulatory Loop and Visual-Spatial Articulatory Loop and Visual-Spatial Sketchpad feed into this systemSketchpad feed into this system

Like the “capacity allocator” of the Like the “capacity allocator” of the attentional systemattentional system

Involved in higher order processing Involved in higher order processing like problem solving and language like problem solving and language comprehensioncomprehension

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Putting it all togetherPutting it all together

SensationsPerceptual processes

AttentionShort-Term

MemoryLong-Term

Memory

Working Memory

CentralExecutive

ArticulatoryLoop

Visual-SpatialSketchpad