BioCog 3B Vision biological Flashcards
1
Q
Basal visual functions
A
- colours, lines, angles
2
Q
higher order visual functions
A
- what
- where
3
Q
transduction
A
- conversion into electrical signals
- photoreceptors to ganglion cells
4
Q
projection
A
- from sensory organ to the brain
5
Q
hue
A
- colour
6
Q
saturation
A
- grade to which a perceived colour has only one wavelength
7
Q
2nd cranial nerve
A
- optic nerve
8
Q
blind spot
A
- where the optic nerves meets the retina
- no rods not cones
9
Q
fovea
A
- point of highest resolution
10
Q
bipolar cells
A
- get signal from photoreceptors
- tranfer to ganglion cells
11
Q
ganglion cells
A
- get signal from the bipolar cells
- merge into the optic nerve
12
Q
receptive field
A
- region of space that induces a change of firing rate for certain neurons
- what the neuron “sees”
13
Q
lamellae
A
- part of photoreceptors
- contain the photopigment
14
Q
cones
A
- for colour
- red, green and blue
- made out of retinal and one of three opsins
15
Q
rods
A
- for brightness
- made up of rod opsin and retinal = rhodopsin
16
Q
brightness
A
= intensity
- coded by firing rate
17
Q
ON cells
A
- fire more when there is more
- have their ON area in the center
18
Q
OFF cells
A
- fire more when there is less
- have their OFF area in the center
19
Q
Mach effect
A
- colour field edges appear lighter when a darker coulour is next to it or vice versa
- due to receptive fields, ON and OFF cells
20
Q
rebound effect
A
- ganglion cells are stimulated / inhibited for a longer time
- stimulus seized
- ganglion cells fire temporarily less or more than
before
- creates afterimage
21
Q
trichromatic coding
A
- red light activates the red cone and so on
22
Q
opponent-process coding
A
- after trichromatic coding
- red-green and blue-yellow cell
- adds yellow
23
Q
red-green ganglion cell
A
ON = red
- OFF = green
24
Q
yellow-blue ganglion cell
A
- ON = yellow
- OFF = blue
25
simple cells
- get signals from single cells of LGN
| - transfer to complex cells
26
complex cells
- get signals from simple cells
| - make f.e. movement detection by combining receptive fields of simple cells
27
retinotopic organization
- an area of the visual field exactly corresponds with an area in the visual cortex
- for location detection
28
depth perception
- mainly by disparity of the eyes
29
striate cortex
= primary visual cortex
30
what
- ventral stream
- inferotemporal cortex
- colour, shape, pattern, faces
- 50% magnocellular
- 50% parvo and koniocellular
31
where
- dorsal stream
- prestriate cortex and posterior parietal cortex
- space, movement, coordination/tracking
- 95% magnocellular
32
V4
- for colour constancy
33
V8
- for colour vision
- colour imagination
- colour memory
34
cerebral achromatopsia
- no colour vision, imagination and memory
| - from damage in V8
35
optic chiasm
- optic nerves switch sides
36
LGN
- lateral geniculate nuclei
- two of them
- 6 layers
37
layer 1 +2
- magnocellular
| - shape, movement, depth
38
layer 3 - 6
- parvocellular
| - colour and details
39
apperceptive agnosia
- inability to recognize objects
| - inability to combine parts
40
propagnosia
- inability to recognize faces
41
face-inversion effect
- upside down face with reversed eyes and mouth
- > you dont find it weird
- turn that upside down
- > very weird
42
IP
- intraprietal sulcus
| - in posterior parietal cortex
43
LIP + VIP
- attention and eye movement
44
VIP + MIP
- visual control of grasping and pointing
45
AIP
- graspin and manipulating with hands
46
CIP
- depth perception
47
V5
- movement perception
| - extra thick and myelinate connections
48
akinetopsia
- inability perceive fluent movements
| - from damage to V5
49
MST
- for optic flow
