Chapter 4Sensation and Perception

How does the world out there get in?

Describe a situation where…1. you experienced difficulty as a result of

failing to hear, see, taste, smell, or feel something around you.

2. you sensed something in the environment but were unable to accurately interpret the info.

sensation• stimulation of sensory receptors and

transmission of sensory information to the central nervous system (CNS)

• occurs when a stimulus activates a receptor

• automatic

perception

• process through which we interpret sensory stimulation– reflects learning, expectations, attitudes

• organization of sensory information into meaningful experiences

Aoccdrnig to rscheearch at Cmabrigde Uinervtisy, it deosn't

mttaer in waht oredr the ltteers in a wrod are, the olny

iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit

pclae. The rset can be a total mses and you can sitll raed it

wouthit a porbelm. Tihs is bcuseae the huamn mnid deos

not raed ervey lteter by istlef, but the wrod as a wlohe.

absolute threshold

• weakest amount of stimulus required to produce a sensation

• (needed to block out extraneous stuff)

difference threshold

• minimum amount of difference a person can detect between 2 stimuli

signal-detection theory

• recognizing stimulus against background of competing stimuli

Red Blue Yellow Green

Orange Blue Red Yellow

Green Orange Blue Red

Red Green Blue Orange

sensory adaptation

• process by which we become more sensitive to weak stimuli and less sensitive to unchanging stimuli

DEMONSTRATIONS FOR 4-2 (THE EYE)

“Seeing is believing.”

PERCEPTIONChapter 4, Section 5

Closure

object = figure surrounding = ground

Proximity

A Review of the Gestalt Rules of Perceptual Organization

• What were the five rules?– proximity, similarity, continuity, connectedness, closure

Stroboscopic Motion

Texture Gradient

Color Constancy