Psychobiology - Ex2 - Ch5/7

Front 1

organization of sensory cortex

Back 1

primary (exists for each modality), nonprimary/secondary (receives direct projection from corresponding primary sensory cortex area)

Front 2

primary somatosensory cortex / somatosensory 1 / S1

Back 2

located in postcentral gyrus, receives touch info from opposite side of body

Front 3

primary motor cortex / M1

Back 3

located in precentral gyrus, executes movement (motor control)

Front 4

flexibility of sensory brain regions

Back 4

association areas (process mixture of inputs from different modalities), polymodal neurons (allow different sensory systems to interact), synesthesia (stimulus in one modality creates sensation in another)

Front 5

encoding of sensory events

Back 5

as streams of APs; stimulus location determined from position of activated receptors; receptive field: stimulus region that affect activity of a cell in a sensory system (i.e. neuron's firing rate)

Front 6

adaptation

Back 6

decline in receptor sensitivity to maintained stimulation

Front 7

suppression of info

Back 7

remove stimulus, central modulation of sensory modulation (higher brain centers suppress/amplify sensory inputs)

Front 8

major roles of eye

Back 8

refraction (focus light from outside body), transduction (light waves > neural signals), transmission (of signals to brain)

Front 9

refraction

Back 9

light passes through CORNEA (transparent outer layer), forms image on RETINA (receptive surface inside eye) via LENS, passes through AQUEOUS HUMOR (fluid behind cornea), regulated by IRIS and PUPIL, passes through VITREOUS HUMOR (fluid between lens and retina)

Front 10

focusing images on retina

Back 10

ciliary muscles (control shape of lens) control accommodation (adjustment of lens to focus), an automatic involuntary muscular movement

Front 11

common refraction problems

Back 11

cataracts (opacities in lenses), presbyopia (far-sightedness due to insufficient accommodation), hyperopia (far-sightedness due to short eyeball), myopia (nearsightedness due to long eyeball),
emmetropia (perfect vision), astigmatism (unequal curving of one eye

Front 12

photoreceptors

Back 12

sensory neurons that transduce light into graded neural signals; rods and cones

Front 13

bipolar cells

Back 13

rods/cones > ganglion cells

Front 14

ganglion cells

Back 14

cells whose axons form optic nerve

Front 15

optic nerve

Back 15

collection of ganglion cell axons extending from retina to brain

Front 16

scotopic vs. photopic systems

Back 16

rods (dim light, insensitive to color) vs. cones (requires more light, allows color vision)

Front 17

convergence

Back 17

specific to rods

Front 18

fovea

Back 18

central portion of retina, containing highest density of photoreceptors (cones); receives direct light input that doesn't pass through other cells of blood vessels, center of gaze

Front 19

peripheral retina

Back 19

rods:cones >20

Front 20

blind spot

Back 20

where optic nerve leaves retina

Front 21

sensitivity vs. acuity

Back 21

rods, quantitative input vs. cones, qualitative input

Front 22

electromagnetic spectrum

Back 22

continuum of electromagnetic energy; visual light ranges 400-700nm

Front 23

wavelength

Back 23

distance between peaks of waves, used to describe light energy

Front 24

transmission

Back 24

retina > optic nerve > crosses optic chiasm, now called optic tract > superior colliculus or lateral geniculate nucleus, latter > visual cortext

Front 25

crossing at optic chiasm

Back 25

info from each visual hemifield sent to controlateral hemisphere of occipital lobe

Front 26

retinal receptive field

Back 26

# of photoreceptors that feed into a ganglion cell

Front 27

light hyperpolarizes photoreceptors

Back 27

causes decreased release of glutamate

Front 28

on-center bipolar cells

Back 28

excited by light in center of its receptive field

Front 29

off-center bipolar cells

Back 29

inhibited by light in center of receptive field

Front 30

bipolar cells also release glutamate

Back 30

causes depolarization in ganglion cells

Front 31

lateral inhibition

Back 31

process in which sensory receptor cells inhibit info from neighboring cells

Front 32

bipolar vs. ganglion cell response

Back 32

changes in local membrane potentials vs. action potentials

Front 33

simple cortical cells

Back 33

respond best to bars of light of a particular width, certain orientation, and particular location in visual field

Front 34

complex cortical cells

Back 34

respond best to movement of bars of light in particular orientation, an in preferred direction

Front 35

varied receptive fields (V#)

Back 35

1 - lines or bars, 2 - illusory contours, complex relations among parts of receptive fields 4 - concentric, radial stimuli; color differences, IT - particular complex forms, 5 - moving visual stimuli

Front 36

visual cortex processing streams

Back 36

ventral, temporal lobe (what - identification); dorsal, parietal lobe (where - location)