Sensory and Short-Term Memory

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Sensory and Short-Term Memory

• PSY 421 Fall 2004

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Overview

• Sensory Memory (Chapter 3, pp. 102-110)
• Short-Term Memory (Chapter 4, pp. 134-157)
• How this fits together with what we have learned
  and what we will learn

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Sensory Memory

• Part of the Information-Processing Model of
  Memory (Atkinson-Shiffrin, 1968)
• Visual Sensory Memory (aka iconic memory)
• Partial vs. Whole Report
• Visual Masking
• Duration Estimation

Information/ Stimuli
Sensory Stores (one per modality)
Short-Term Store
Long-Term Store
Rehearsal
Attention
Retrieval
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Visual Sensory/Iconic Memory

• Precategorical Nature
• Iconic Memory who cares!
• Useful if you are reading during a lightening
  storm
• Important for preventing overloading of cognitive
  system

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Auditory Sensory Memory

• Echoic Memory
• Everyday problem if we didnt have echoic
  memory, would be able to remember the beginning
  of a sentence said aloud by the time we reached
  the end?
• Partial vs. Whole Report
• Modality and Suffix Effects

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Partial vs. Whole Report

• George Sperling (1960) how much information
  could be taken in during a glance of a very
  briefly presented stimulus?
• T-scope presentation for no-fade screen refresh
• Present matrix for 50 msec
• Tone subjects were to report everything in the
  matrix (whole report) 3 to 4 letters typically
  reported
• Partial Report High tone subjects were to
  report top row - 3 of the 4 letters typically
  reported mid and low tones too
• Duration between presentation and tone was
  important more than a quarter of a second, only
  50 could be reported

A C K L W T P Z Q
R D M
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Precategorical Acoustic Store

• Evidence for
• Evidence against

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Short-Term Memory (STM)

• Also known as Working Memory, primary memory
• Set of processes that we use to hold and rehearse
  information that occupies our current awareness
• Is this really different from Long-Term Memory?
• Characteristics of STM
• Limited Duration
• Limited Capacity
• Information is coded with auditory characteristics

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Forgetting in STM

• Decay loss of information due to the passage of
  time
• Interference loss of information due to
  negative influence from the presentation of other
  information

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Working Memory

• More elaborate conception of STM
• Baddeley and colleagues primary researchers
• Working Memory (WM) is a set of closely
  interacting subsystems that combine to subserve a
  hot of higher-level mental processes
• Subsystems
• Articulatory Loop
• Visual-Spatial Sketch Pad
• Central Executive THE system

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Articulatory Loop

• Phonological Store holds information
  temporarily
• Subvocal Rehearsal just what is appears to be
• Articulatory Suppression

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Visual-Spatial Sketchpad

• Responsible for storage and manipulation of
  visual and spatial information
• Seems to work independently from articulatory loop

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Central Executive

• Articulatory Loop and Visual-Spatial Sketchpad
  feed into this system
• Like the capacity allocator of the attentional
  system
• Involved in higher order processing like problem
  solving and language comprehension

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Putting it all together

Sensations
Perceptual processes
Attention
Short-Term Memory
Long-Term Memory
Working Memory
Central Executive
Articulatory Loop
Visual-Spatial Sketchpad