Sensation and Perception

Question 1

stimulus

Answer 1

• elicits reaction from sensory systems

Question 2

transduction

Answer 2

translation from stimulus to neural signal

Question 3

sensory adaptation

Answer 3

pay less attention to a non changing source of stimulation

Question 4

selective attention

Answer 4

prioritize input to focus on avail info and exclude the rest

Question 5

bottom-up processing

Answer 5

building simple input into more complex perceptions
eg. learning a new word

Question 6

top-down processing

Answer 6

stuff u know already help u interpret incoming sensory info
eg. recognizing a friend

Question 7

psychophysics

Answer 7

Gustav Fechner
- relationship between physical qualities of stimuli and response they produce

Question 8

absolute threshold

Answer 8

smallest amount of stimulus that can be detected
eg. seeing light from a candle flame 30 miles away at night

Question 9

difference shreshold

Answer 9

smallest detectable difference between 2 stimuli
eg. difference between 2 weights

Question 10

signal detection

Answer 10

detection of faint, uncertain stimuli
1. intensity of stimulus
2. criteria for deciding whether stimulus occurred

Question 11

vision

Answer 11

• process reflected light
• approx 50% of cerebral cortex processes visual info

Question 12

visual stimulus

Answer 12

visible light or energy within electromagnetic spectrum that our visual system responds to

Question 13

cornea

Answer 13

clear surface at front of eye that begins to bend light into eye

Question 14

pupil

Answer 14

opening formed by iris

Question 15

iris

Answer 15

adjusts opening of pupil in response to amount of light and in response to signals from the autonomic nervous system

Question 16

lens

Answer 16

bends light toward retina

Question 17

retina

Answer 17

layers of visual processing cells in back of eye - converts light into electrical signals

Question 18

fovea

Answer 18

• part of retina for highly detailed vision
• central vision
• image of object we stare directly at is projected onto fovea

Question 19

rod

Answer 19

photoreceptor detecting dim light
- more in PHERIPHERY of retina
- provide no colour, clear or sharp images
- around 90 million rods

Question 20

cone

Answer 20

photoreceptor processing colour and detail
- functions best under sharp, bright light
- 4-5 million cones

Question 21

blind spot

Answer 21

optic nerve exit w/o rods or cones

Question 22

optic nerve

Answer 22

nerve exiting retina of eye

Question 23

partial crossing

Answer 23

• axons closest to nose cross over to other hemisphere while axons on outside go to same hemisphere
• everything to the left of centre in visual field is processed by the right hemisphere and vice versa

Question 24

trichromatic theory

Answer 24

based on existence of different types of cones for detection of short (blue), medium (green) and long (red) wavelengths

Question 25

opponent process theory

Answer 25

we have red-green and blue-yellow color channels - if u stare at one colorand then look at a white wall you'll start to see the other

Question 26

colorblind

Answer 26

- people who have two types of cones instead of the usual three

Question 27

organization principle

Answer 27

identify main object in the scene

Question 28

proximity principle

Answer 28

objects that are close together tend to be grouped together

Question 29

continuity principle

Answer 29

we assume that points which form smooth lines when connected belong together

Question 30

closure principle

Answer 30

we "fill in the blanks" when we see an image made of lines or gaps

Question 31

simplicity principle

Answer 31

we will use the simplest solution to a perceptual problem

Question 32

depth perception

Answer 32

ability to use 2D image projected onto retina to perceive 3D

Question 33

monocular cue

Answer 33

depth cue using only ONE eye - texture gradients and shading - occlusion: blocking distant object by closer objects

Question 34

binocular cue

Answer 34

- use both eyes - retinal disparity: difference between images projected onto each eye - provides info of relative distance between two objects