PSYCH 110 EXAM 2

Sensation

Sensation

detection of physical stimuli and transmission of that information to the brain

distal stimulus

an object or event in the outside world

proximal stimulus

the energies from the outside world that directly reach our sense organs

bottom-up processing

analysis based on the physical properties of the stimulus

transudction

the translation of physical stimuli received by sensory receptors into neural signals that the brain can interpret

Gestalt principles of perceptual organization

proximity, similarity, good continuation, closure, common fate

Cones

- less sensitive to low levels of light

- responsible for vision under brighter conditions

- responsible for color vision and fine detail

- located mostly in the center of the retina

Rods

- respond at extremely low levels of light

- primarily responsible for night vision

- do not support color vision

- poor at fine detail

- located at the retina's edges

Fovea

the central focal point in the retina, around which the eye's cones cluster

color constancy

the perceived color of objects remains constant under differing illumination

object constancy

an understanding that objects remain the same, irrespective of differences in viewing condition

binocular rivalry

the phenomenon in which conscious perception alternates between images shown separately to each eye, rather than the perception of a "mixed" image

extrastriate cortex

a region of the occipital lobe (and partially temporal) outside of V1

includes: V3, V4, V5/MT, FFA, and PPA

PPA

Parahippocampal place area. responds preferentially to places, such as pictures of houses.

ventral stream

what pathway

dorsal stream

where pathway

eardrum

a thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate

cochlea

the spiral cavity of the inner ear containing the organ of Corti, which produces nerve impulses in response to sound vibrations.

stereocilia

protein filaments that brush up against the tectorial membrane (when vibrated from below)

medial geniculate nucleus

nucleus of the thalamus that receives auditory input

primary auditory cortex

the region of the superior temporal lobe whose primary input is auditory information

auditory stream segmentation

rapid alternation of high and low pitched tones create the illusion of two sound sources, due to perceptual grouping

Cocktail party effect

the phenomenon of filtering out a range of stimuli (visual, auditory, touch, etc) while focusing auditory attention on a particular stimulus.

dichotomous listening task

two different auditory stimuli are presented simultaneously (one in each ear), and the patient is asked to repeat one auditory stream while ignoring the other stimuli

blue

400-500nm

green

500-550

yellow

570-580

lateral inhibition

the ability of an active neuron to inhibit the activity of adjacent neurons

tonotopic map

representation in the auditory cortex of different sound frequencies

Perception

the further processing, organizing, and interpretation of sensory information

top-down processing

processing based on prior existing world knowledge, expectations, and past experiences

adequate stimulus

form of stimulus/energy to which a receptor is most responsive

FFA

Fusiform Face Area. Responds to faces

more than other objects

Organ of Corti

Center part of the cochlea, containing hair cells, canals, and membranes

continuity illusion

ability to percieve sounds as continuous if the gaps are "filled in" with something else that can be interpreted as the reason for the gap

Shepard Tone

playing of one or more streams of sequential tones (each separated by an octave) and fading out one stream while fading in the other creates the perception of continually rising (or descending) pitch

red

600-700

interaural time difference

the time interval between when a sound enters one ear and when it enters the other ear

interaural level difference

the difference in level (intensity) between a sound arriving at one ear versus the other

acoustic shadow

The shadow created by the head that decreases the level of high-frequency sounds on the opposite side of the head.

The acoustic shadow is the basis of the localization cue of interaural level difference.

retinotopic map

the two dimensional representation of the retinal image in the neurons of the primary visual cortex

double dissociation

when two related mental processes are shown to function independently of each other