Module 3:Sensation and Perception

Sensation

when sensory info is detected by a sensory receptor

transduction

conversion from sensory stimulus to action potential

absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time

difference threshold

the minimum difference between two stimuli required for detection 50 percent of the time

Perception

the way sensory info is organized, interpreted, and experienced

bottom up processing

the way the brain interprets sensory info starting with basic sensory input working to complex interpretation

top down processing

how the brain uses prior knowledge, expectation, and context to interpret sensory information

sensory adaptation

not receiving stimuli that remains constant over prolonged period of time

inattentional blindness

failure to notice something completely visible due to lack of attention

signal detection theory

the ability to identify a stimulus when it's embedded in a distracting background

trichromatic theory of color vision

all colors can be produced combining red, green, and blue

opponent process theory

color is coded in opponent pairs black-white, yellow-blue, and green-red

afterimage

continuation of visual sensation after the removal of a stimulus

depth perception

ability to perceive spatial relationships in 3-D space

binocular cues

relies on both eyes to experience depth 3-D

binocular disparity

slightly different view each eye sees

monocular cues

required one eye, 2-D world

linear perspective

parallel line seem to converge in the distance, creates illusion of depth on 2-D surface

pitch perception

our ability to distinguish and order sounds from low to high based on their frequency

temporal theory

suggests frequency is coded by the activity level of a sensory neuron

place theory

suggests different portion of the basilar membrane are sensitive to sounds of different frequencies

sound localization

the ability to locate sound

monaural cues

one eared, locates sound above, below, behind or in front, essential for determining sound elevation

binaural cues

two eared, relies on differences in vibration between ears to determine horizontal location

interaural level difference

difference in sound intensity perceived by each each when a sound is located on one side

interaural timing difference

small difference in the time when arrives at each ear

chemical senses

senses that have sensory receptors that respond to molecules in food or air

taste buds

groupings of taste receptor cells

taste perception

food molecules binds to taste cells' receptors this triggers the creation of neural signal

olfactory receptor

sensory cell for the olfactory system

olfactory bulb

at the tip of the frontal lobe where olfactory nerves begin

meissner's corpuscles

responds to pressure and low frequency vibrations

pacianian corpuscles

detects transient pressure and high frequency vibrations

merkel's disks

responds to light pressure

ruffini corpuscles

detect stretch

thermoception

temperature perception

nociception

signal potential harm and pain

inflammatory pain

signals for tissue damage

neuropathic pain

pain signal that are sent to the brain

vestibular sense

helps with the ability to maintain balance and body posture, inner ear

proprioception

perception of body position

kinesthesia

perception of body movement

Gestalt Principles

organizing elements as wholes rather than parts

figure ground relationship

separating the visual world in figure(person/object) and ground (background)

proximity

things that are close together tend to be grouped

similarity

things are alike are grouped

law of continuity

more likely to perceive continuous lines over broken ones

principle of closure

organizing perception into complete objects instead of parts