Introduction to Cognitive Science(COGN1001)

Psychology Module (i)

• Nature of Human Mind• Cognitive Psychology

– Information processing system– The architecture of the mind

Information Processing Model • Computer as an analogy

– Select, encode, store & retrieve

• Empirical investigation & evidence

Sensory Memory • Echoic memory• Iconic memory

• Visual summation– Phi phenomenon– E.g., movies

• Backward masking

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John

is

going

to

tell

you

a

story

Sensory Memory (cont’d)

• Temporal limitation– Brief

• Storage – Relatively large

• Capacity?• Duration?

Sperling (1960)• 3 x 3 letter matrix• 3 x 4• .15, .30, .50 msecs delay• Whole report• Partial report technique

Sensory Memory (cont’d)

• Capacity– Relatively large

• Duration– 250 msecs

• Function:

• Information loss:– Decay

Attention

Theories of Attention• Early selection (Broadbent)

• Dichotic listening• Left ear: 7 4 1• Right ear: 3 2 5

• Contrasting findings:– Shadowing– Attended message:

“They were throwing stones at the bank”

– Unattended message: “money” rather “river”

– Tended to remember: “They were throwing stones at the financial institution”

• Cocktail party phenomenon

• Attenuation (Treisman)

• Late selection (Deutsch & Deutsch)• Capacity model (Kahneman & others)

• Selective attention• Divided attention

• Attention– Unavoidable– E.g., Stroop effect

RED BLUE GREEN ORANGE

RED BLUE GREEN ORANGE

Short-term Memory

• Encoding

• How is information encoded?– Demo

+

T L P K S J

T L P K S J

P B

P R

Acoustic confusion

Short-term Memory (cont’d)

• How can you keep the info in your STM?

• Capacity?– Demo

+

F B I S A R U C S I B M

+

0 0 1 0 1 1 1 0 1 0 0 0 1 0 1

+

Lake Bread Jump Sing

Song Pen Water Hop

Paper Butter

F B I S A R U C S I B M(7)

0 0 1 0 1 1 1 0 1 0 0 0 1 0 1(9)

Lake Bread Jump SingSong Pen Water Hop

Paper Butter(5)

Short-term Memory (cont’d)

• Storage limitation– 7 + 2 items (George Miller, 1956)

• Chunking

28571017

2857-1017

F B I S A R U C S I B MF B I -S A R- U C S- I B M

0 0 1 0 1 1 1 0 1 0 0 0 1 0 10 0 1 -0 1 1- 1 0 1- 0 0 0- 1 0 1

Lake Bread Jump SingSong Pen Water Hop

Paper Butter

Lake Water Bread ButterJump Hop Sing Song

Paper Pen

Short-term Memory (cont’d)

• Duration?– How can we go about to test it?

Working MemoryBaddeley (1989)

• 3 components:– Articulartory loop– Visuospatial sketchpad– Executive control system

(e.g., simple arithmetic)

– Limited resources– Digit span & Arithmetic

• Digit span– English 7.3– Chinese 9.9

Working Memory (cont’d)

• Information loss– Displacement– Interference– Decay