PSY 210 VISUAL AND AUDITORY Flashcards
sensory systems: creating ___ of world
perception
sensation:
interaction of physical world and sensory organ
sensory organs
skin, eyes, ears, tongue
perception:
what you do with sensory info; how you process
perception of world is ___
artificial
perceptions based on ability to ___
perceive world
4 aspects to sensory organ
- physical aspect
- specialized receptors
- specialized input
- specialized processors
VISION: 1. physical aspects of ___
light
what can we see on the electromagnetic spectrum?
400 nm - 760 nm
waves.. BRIGHTNESS
amount of energy
changes in amplitude =
changes in light
great amplitude ==
bright colors
small amplitude ==
dull colors
peak-to-peak
wavelength
top of wave=
bottom of wave=
peak
troph
top of wave TO bottom
amplitude
wavelength
distance between wave peaks
what we perceive as color:
wavelength
color white
light at every wavelength equally
do objects have color?
NO, they reflect color
color black
fewer/no light at wavelengths
eye anatomy
cornea
iris and pupil
lens
retina
eye sensory organ:
eyeball
what does eye anatomy do
focus light to back of eye
cornea
outermost part of eye, window-like
iris
opens and closes
pupil
opens in dark light
closes in bright
lens
thick frame; can be stretched and shrinked
retina
receptors in back of eye
FOVEA
center of receptors
“foveating”
“focusing”
blind people don’t have a __
fovea
light is reflected onto __
all angles of eyeball
receptors only
sense light
TRANSDUCTION
change of physical energy to neuronal energy
transduction in vision starts @
rods/cones
3 levels of cells in fovea
- photoreceptors (rods/cones)
- bipolar cells
- ganglion cells
photoreceptors AKA
rods/cones
pigment in rods and cones does ….
- bleaches pigment of photopigment
- creates action potential
center surround organization is
antagonistic , center is inhibitory, outside is excitatory (vice-versa)
displacement
how waves get displaced
receptive field
- region of space in which neurons respond when a stimulus enters it
- This causes neurons in the visual system to represent space
- This external space is represented by different receptive fields of neighboring cells
- Allows the space to be represented fully by certain neuronal regions (LGN or V1)
retinotopic map
- full map using neighboring neurons
center surround organization
- allows us to perceive the edges of objects
- without it we wouldn’t know where one thing started and where one thing ended
visual pathway starts at
rods/cones
light coming in pathway:
eye - retina - ganglion cells - optic nerves - optics chiasma - lateral geniculate body of thalamus - striate cortex
1st synapse at
optic chiasma
lateral geniculate body of thalamus =
visual thalamus
striate cortex AKA
V1
AND
primary visual cortex
striate cortex is in what lobe
occipital lobe
what does retina and cortex absorb
RETINA = spots of lights CORTEX = light bars and gratings
2 visual pathways
parietal pathway
temporal pathway
parietal pathway is (anatomically)
dorsal
temporal pathway is (anatomically)
ventral
parietal pathway answers
“where”
- spatial processing
temporal pathway answers
“what”
- object perception
parietal pathway …
listed
M-ganglion - magno (large) LGN - V1 - V2 - V3 -
– MT (movement) - parietal lobe
LGN
lateral geniculate nuclei
temporal pathway …
listed
P-ganglion - parvo (small) LGN - V1 - V2 - V3 -
– V4 (color) - IT (form)
2 visual routes
superior longitudinal pathway/fasciculus - posterior parietal cortex
inferior longitudinal pathway/fasciculus - inferior temporal cortex
pathway aka
fasciculus
superior longitudinal pathway/fasciculus
ROUTE TO
dorsal route to parietal lobe
inferior longitudinal pathway/fasciculus
ROUTE TO
ventral route to temporal lobe
functional dissociation experiment
ungerlieder & mortimer ‘82
physiological support for what-where
monkey lesions/contingency task
contingency task - LT
landmark task
- cylinder as landmark
1: mark food
2: mark empty cell - switch of contingency
contingency task - ODT
object discrimination task
- cylinder as landmark
1: mark food
2: mark empty cell - cube as distracter
- SWITCH
parietal lesions
(single dissociation)
disruption of “where” = poor performance of landmark task after initial contingency
temporal lesions
(bi-lateral)
disruption of “what” = couldn’t distinguish between objects in object discrimination task
- slower initial learning
- worse switching
what did monkey lesions experiment do
- shows that systems are seperate from each other
pathways make how much of visual stream
90%
occipital cortex
other percentage of visual stream
10% superior colliculus (midbrain in brainstem) pulvinar nucleus (thalamus)
3 attributes in audition physical aspects
- amplitude = wave height
- wavelength = peak to peak
- frequency = # of cycles per second
LOUDNESS
different displacement
audition amplitude
wave height
audition wavelength
peak to peak
audition frequency
of times per second a wave cycles from highest to lowest pitch
Frequency also affects loudness, with higher-pitched sounds being perceived as louder. Amplitude and frequency of sound waves interact to produce the experiences of loudness and pitch.
sin wave reading
waves across time
pitch
depends most on the frequency of sound waves
the higher the frequency…
… the higher the pitch (wavelengths are closer)
frequency is measured __
in hertz (cycles per second)
what’s audible for humans
sounds between 20 and 20,000 hertz
timbre
quality of sound
timbre depends on
complexity of sound wave
breaking down complex waves to simple -
graph axes
frequency domain (amp) VERSUS time domain
- fundamental: associated w/ pitch
audition ear anatomy (input system) - BASIC
external ear
middle ear
inner ear
external ear
pinna
ear canal
middle ear
tympanic membrane
ossicles
eardrum
tympanic membrane
ossicles
[BOTH]
hammer
anvil
stirrup
malleus
incus
stapes
inner ear
cochlea
semicircular canals
vestibular sacs
cochlea shaped like:
snail-like
audition: specialized receptors
basilar membrane
- HAIR CELLS
where does transduction occur in audition?
hair cells at basilar membrane
– bend when fluid vibrates
audition pathway
dorsal/ventral nucleus - (pons) superior olivary nucleus - (midbrain) inferior colliculus medial geniculate - (cortex) audtory cortex [A1, A2]
cortex contains ___
tonotopic map ; organized by frequency
convergence in retina
lots of rods and cones, fewer bipolar cells, fewer ganglion cells
– GETS SMALLER
lateral inhibition in RETINA - created by ___
horizontal & amacrine cells
lateral inhibition
- connect cells laterally (in between rods/cones AND bipolar, between bipolar AND ganglion)
- perpendicular to information connections
rods are mostly in ___
peripheral
cones are mostly in ___
fovea
how many cones are there
3
cones perceive __
color
rods perceive __
light
