Week6 Flashcards
lens
It is focused by the lens
Light road
Light enters the eye through an opening in the center of the
iris called the pupil
It is focused by the lens (adjustable)
cornea (not adjustable)
projected onto the retina
The Opponent-Process Theory
brain has a mechanism that perceives color on a continuum from red
to green
cell fatigue makes this possible
afterimages depend on
the whole context, not just the light on individual receptors
The Retinex Theory
color constancy
Most of the optic nerve goes to
the lateral
geniculate nucleus of the thalamus
Part of the visual input goes to theSuperior
colliculus
Superior
colliculus
Retina’s way of sharpening contrasts to emphasize the borders of objects?
Lateral inhibition(cones)
light striking the rods and cones decreases
their spontaneous output, and the receptors make inhibitory synapses onto the bipolar cells. light on the
rods or cones decreases their inhibitory output.
aphantasia
no visual imagery
blindsight
the ability to respond to visual information without perceiving it consciously.
Magnocellular cells are specialized to respond to wha
Movement
How do complex cells in the visual cortex differ from
simple cells?
Complex cells make the same response after a stimulus moves
inferior temporal cortex
recognize familiar objects
Visual agnosia
damage to the ventral pathway
fusiform gyrus
Part of the parahippocampal cortex (next to the hippocampus) responds mostly to the sight of places.
prosopagnosia
impaired ability to recognize faces.
damage to the right fusiform gyrus
or fewer connections between it and the occipital cortex.
sound perception road
When sound waves strike the tympanic membrane in (a), they vibrate three tiny bones—the hammer, anvil, and stirrup—that convert the sound
waves into stronger vibrations in the fluid-filled cochlea (b). Those vibrations displace the hair cells along the basilar membrane in the cochlea.
(c) A cross-section through the cochlea. (d) A close-up of the hair cells.
High-frequency sounds excite hair cells near the base. Low-frequency
sounds excite cells near the apex
conductive deafness or middle-ear deafness,
corrected by surgery
or hearing aids. Because people with conductive deafness
have a normal cochlea and auditory nerve, they readily
hear their own voices, conducted through the bones of the
skull directly to the cochlea, bypassing the middle ear
Nerve deafness, or inner-ear deafness
results from
damage to the cochlea, the hair cells, or the auditory nerve.
localizing
Humans localize high-frequency sounds according to
differences in loudness between the ears. We localize
low-frequency sounds by differences in phase
Which structure enables us to localize sounds in the updown axis?
The pinna
Eardrum
vibrates with air pressure waves
Middle ear ossicles
transmit vibration to oval window
(hammer, anvil , stirrup)
Cochlea
where specific
frequencies are encoded - Basilar membrane with hair cells (cilia)
Auditory nerve
encodes stimulus
aspects and relays this to primary
auditory cortex
Auditory pathway
cochlea
Cochlear nucleus
Inferior colliculus
Medial geniculate nucleus
primary auditory cortex in superiortemporal lobe
Multiple crossing places
- sound
from each ear is processed in each
hemisphere - Irrespective of sound location
vestibular organ
Wrapped around cochlea
Three semicircular canals filled with hair cells and fluid
Signal is processed in brain stem
Taste
Receptors are taste buds on the papilla of the tongue
Large individual differences in sensitivity, partly
accounted for by genetic factors and hormones
Smell
Receptors are inside the nose, based on airborne substances
influenced by hormones
