Mcat Behavioral Sciences Chapter 2

Front 1

sensation

Back 1

conversion or transduction of physical, electromagnetic, auditory, and other info form the internal and external environment into electrical signals in the nervous system

Front 2

perception

Back 2

processing of sensory info to make sense of the significance.

Front 3

sensory receptors

Back 3

nerves that respond to stimuli and trigger electrical signals

Front 4

sensory ganglia

Back 4

collections of cell bodies outside the CNS

Front 5

common sensory receptors

Back 5

1. photoreceptors

2. hair cells

3. nociceptors

4. thrmoreceptors

5. osmoreceptors

6. olfactory

7. taste

Front 6

threshold

Back 6

minimum stimulus that causes a change in signal transduction

Front 7

absolute threshold

Back 7

min. of stimulus energy needed to activate a sensory system

Front 8

threshold of conscious perception

Back 8

the minimum stimulus energy that will create a signal large enough in size and long enough in duration to be brought into awareness

Front 9

difference threshold

Back 9

min. diff. in mag. between 2 stimuli before once can perceive the difference.

Front 10

weber's law

Back 10

that DF or JND for a stimulus is proportional to the magnitude of the stimulus and that this proportion is constant over most of the range of possible stimuli

Front 11

signal detection theory

Back 11

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

Front 12

response bias (through signal detection experiment)

Back 12

in an experiment a stimulus may or may not be given and the subject is asked to state whether or not the stimulus was given. There are four possible outcomes: hits, misses, false alarms, or correct negatives.

Front 13

adaption

Back 13

decrease in response to stimulus over time

Front 14

cornea

Back 14

gathers and filters light

Front 15

iris

Back 15

colored part, divides the eye into the anterior and posterior chamber. It has two muscles: the dilator and constrictor pupillae which open and close the pupil.

Front 16

lens

Back 16

refracts incoming light to focus it on the retina and is held in place by suspensory ligaments connected to the cilliary muscle

Front 17

aqueous humor

Back 17

produced by the ciliary body and drains through the canal of schlemm.

Front 18

rods

Back 18

detect light and dark

Front 19

cones

Back 19

come in three forms (Short, medium, long) to detect colors

Front 20

where are cones located

Back 20

in the retina in the macula which corresponds to the central visual fields. The center of the macula is the fovea which contains only cones.

Front 21

signal transduction in the eye

Back 21

rods and cones synapse on bipolar cells, which synapse on ganglion cells. Edge sharpening is performed by horizontal and amacrine cells.

Front 22

visual pathway

Back 22

eye, optic nerves, optic chiasm, optic tracts, lateral geniculate nucleus of the thalamus, visual radiations to get to the visual cortex.

Front 23

optic chiasm

Back 23

contains fibers crossing from the nasal side of the retina of both eye

Front 24

visual radiations

Back 24

run through the temporal and parietal lobes

Front 25

visual cortex

Back 25

occipital lobe

Front 26

how is vision processed

Back 26

through parallel processing: the ability to analyze and combine info regarding color, shape, and motion

Front 27

how is shape detected?

Back 27

parvocellular cells

Front 28

how is motion detected?

Back 28

magnocellular cells

Front 29

ear division (3)

Back 29

1. outer

2. middle

3. inner

Front 30

outer ear (3 parts)

Back 30

1. pinna

2. external auditory canal

3. tympanic membrane

Front 31

middle ear (3 parts)

Back 31

1. ossicles: malleus, incus, stapes

2. oval window

3. eustachian tube

Front 32

inner ear (components)

Back 32

1. bony labyrinth

2. membranous labyrinth

3. perilymph

4. endolymph

5. cochlea

6. utricle and saccule

semicircular canals

Front 33

perilymph

Back 33

fills the bony labyrinth

Front 34

endolymph

Back 34

fills the membranous labyrinth

Front 35

cochlea

Back 35

detects sound

Front 36

utricle and saccule

Back 36

detect linear motion

Front 37

semicircular canals

Back 37

detects rotational acceleration

Front 38

auditory pathway

Back 38

cochlea, travels thought the vestibulocochlear nerve and medial geniculate nucleus of the thalamus to the auditory cortex in the temporal lobe

Front 39

superior olive

Back 39

localizes sound

Front 40

inferrior colliculus

Back 40

involved in startle reflex

Front 41

olfactory pathway

Back 41

olfactory nerves, olfactory bulb, OF tract, limbic system.

Front 42

somatosensation (4 modalities)

Back 42

pressure, vibration, pain, temp.

Front 43

2 point threshold

Back 43

min distance between two points of stimulation on skin the the points will be felt as 2 distinct stimuli

Front 44

physiological zero

Back 44

normal temp of the skin to which objects are compared to determine if they are hot or cold.

Front 45

noicerecptors

Back 45

detect pain

Front 46

gate theory of pain

Back 46

pain sensation if reduced when other ss signals are present

Front 47

kinesthetic sense

Back 47

the ability to tell where one's body is in 3D space

Front 48

bottom-up processing

Back 48

recognition of objects by parallel processing. Slower but less prone to mistakes

Front 49

top-down processing

Back 49

recognition of objects by memories and expectations, with little attention to detail. faster but prone to mistakes

Front 50

Gestalt principles

Back 50

ways that the brain can infer missing parts of picture when a pic is incomplete

Front 51

GP: law of proximity

Back 51

elements close to one another tend to be perceived as a unit

Front 52

GP: law of similarity

Back 52

objects that are sim appear to be grouped together

Front 53

GP: law of good con.

Back 53

elements appear to follow the same pathway tend to be grouped together

Front 54

GP: subjective contours

Back 54

perception of non-existent edges in figures

Front 55

GP: law of closure

Back 55

when a space is enclosed by a group of lines, it is perceived as a complete or closed line

Front 56

law of pragnanz

Back 56

perceptual organization will always be as regular, simple, and symmetric as possible.