BHS 499-07Memory and Amnesia

Working Memory

Baddeley’s Model

Baddeley and Hitch’s (1983) tripartite (three-part) model

Central executive• Control center of working memory

Two slave systems:• Phonological loop -- processes

verbal/acoustic information

• Visuo-spatial sketchpad -- processes visual and spatial information

Phonological Loop

Components:• Phonological store – temporary store for

speech input

• Articulatory loop – where subvocal rehearsal happens (our inner voice)

Word length effect – word span is smaller for long words than for short ones.

Other Phonological Effects

Articulatory suppression – talking about something makes it difficult to remember something else.

Irrelevant speech effect – background speech, even in another language, interferes with phonological processing.

Phonological similarity effect -- rhyming causes confusion at recall.

Lexicality Effect

Working memory can be affected by the contents of long term memory.• Memory spans are larger for lists of words

than for non-words. Long-term memory supports and

enhances phonological processing and can even reverse some effects.• Rhyming in the context of songs or sentences

helps, not hurts recall.

Visuo-Spatial Sketchpad

Operations of the visuo-spatial sketchpad:• Mental scanning – occurs as if seeing the

actual object.

• Mental rotation

• Boundary extension – people redraw images with boundaries not present in the original.

• Dynamic memory – interpretation of perceived motion.

Representational Effects

Representational momentum – people extrapolate along the current trajectory to predict an object’s final resting place.

Representational gravity – memory for object positions is distorted toward the earth.

Representational friction – objects moving in space slow down with friction.

Context affects these phenomena (church steeple vs rocket ship)

Central Executive

Allocates attentional resources to accomplish tasks.• A catch all explanation for cognition theories.

Distributes memory resources. Memory can be improved by increasing

arousal and thereby working memory resources.• More sleep, gum chewing increases arousal

Central Executive (Cont.)

Suppression – used to keep irrelevant info out of working memory.

Dysexecutive syndrome – disorder involving loss of central exec. function• Perseveration – difficulty disengaging from

one function and switching to another.

• Distraction – drifting thought processes that lock onto some environmental stimulus.

Span Tests

Simple – one cognitive function at a time Complex – two components:

• Retention

• Active processing – more than STM Reading Comprehension Operation Spatial