Chapter 2: Sensation and Perception

Question 1

Sensation

Answer 1

the conversion, or transduction of physical, electromagnetic, auditory, and other information from the internal and external environment into electrical signals

Question 2

Perception

Answer 2

the processing of sensory information to make sense of its significance

Question 3

Sensory Receptors

Answer 3

neurons that respond to stimuli and trigger electrical signals

Question 4

Projection Area

Answer 4

areas in the brain which further analyze sensory input

Question 5

Threshold

Answer 5

the minimum amount of a stimulus that renders a difference in perception

Question 6

Absolute Threshold

Answer 6

the minimum of stimulus energy that is needed to activate a sensory system

Question 7

Just Noticeable difference

Answer 7

refers to the minimum difference in magnitude between two stimuli before one can perceive this diffeence

Question 8

Weber’s Law

Answer 8

there is a constant ratio between the change in stimulus magnitude needed to produce a jnd and the magnitude of the original stimulus

Question 9

Signal Detection Theory

Answer 9

refers to the effects of nonsensory factors such as experiences, motives, expectations, on perception of stimuli

Question 10

Adaption

Answer 10

refers to a decrease in response to a stimulus over time

Question 11

response bias

Answer 11

tendency of subjects to systematically respond to a stimulus in a particular way due to nonsensory factos

Question 12

catch vs noise trials

Answer 12

catch trials are trials in which the signal is presented and noise trials are trials where the signal is not presented

Question 13

sclera

Answer 13

a thick structural layer that covers the most of the exposed portion of the eye, also known as the white of the eye.

Question 14

blood vessels in the eye

Answer 14

choroidal and retinal

Question 15

retina

Answer 15

the innermost layer of the eye which contains the photoreceptors that transduce light into electrical information for the brain

Question 16

cornea

Answer 16

this is where light passes through first when entering the eye and is a clear domelike window in the front of the eye

Question 17

iris

Answer 17

the colored part of the eye

Question 18

muscles of the eye

Answer 18

dilator pupillae (opens the pupil under sympathetic stimulation) and constrictor pupillae (constricts the pupil under parasympathetic stimulation)

Question 19

ciliary body

Answer 19

continuous with the choroid and the iris and produces aqueous humor which bathes the front part of the eye before draining into the canal of Schlemm

Question 20

lens

Answer 20

lies behind the iris and helps control the refraction of incoming light

Question 21

ciliary muscle

Answer 21

contraction under parasympathetic control and it pulls on the suspensory ligaments and changes the shape of the lens in a process known as accomodation

Question 22

vitreous

Answer 22

a transparent gel that supports the retina behind the lens

Question 23

retina

Answer 23

in the back of the eye and is functioning to convert incoming photons of light to electrical signals.

Question 24

duplicity theory of vision

Answer 24

states that the retina contains two kinds of photoreceptors: those specialized for light-and-dark detection and those specialized for color detection.

Question 25

cones

Answer 25

retina made up of approximately 6 million cones and they are used for color vision and to sense fine details most effective in bright light and come in three forms

Question 26

rods

Answer 26

retina made up of 120 million rods and they are more functional and only allow sensation of light and dark because they all contain rhodopsin (night vision)

Question 27

fovea

Answer 27

the very center of the central section of the retina (macula) contains exclusively cones in the fovea

Question 28

connection between rods and cones to optic nerve

Answer 28

rods and cones connect with bipolar cells, which highlight gradients between adjacent rods or cones, bipolar cells synapse with ganglion cells which group together to form the optic nerve

Question 29

amacrine and horizontal cells

Answer 29

receive input from multiple retinal cells in the same area before the information is passed on to ganglion cells. These cells are important for edge detection as they increase our perception of contrasts

Question 30

visual pathways

Answer 30

starts from the eye and travels through the optic nerves, optic chiasm, optic tracts, later geniculate nucleus of the thalamus, and visual radiations to get to the visual cortex

Question 31

parallel processing

Answer 31

the ability to simultaneously analyze and combine information regarding color, shape, and motion

Question 32

parvocellular cells

Answer 32

high spatial resolution and low temporal resolution allowing us to detect shape

Question 33

magnocellular cells

Answer 33

low spatial resolution and high temporal resolution allowing us to detect motion

Question 34

pathway of sound

Answer 34

soundwave reaches the pinna (auricle) and then channels the sound wave to the external auditor canal which directs sound to the tympanic membrane (eardrum)

Question 35

tympanic membrane

Answer 35

the eardrum which vibrates in phase with the incoming sound waves and the frequency of the sound wave determines the rate at which the tympanic membrane vibrates. moves faster for high frequency sounds and more slowly for low frequency sounds louder sounds have greater intensity corresponding to an increased amplitude of this vibration