Vision

Question 1

Hue

Answer 1

dimension of colour determined by wavelength of light

Question 2

Intensity

Answer 2

amount of energy in a wave determined by amplitude

Question 3

Pupil

Answer 3

adjustable opening in the center of the eye

Question 4

Iris

Answer 4

ring muscle forming the coloured portion of eye around pupil controlling size of pupil

Question 5

Lens

Answer 5

transparent structure behind pupil that changes shape to focus images on the retina
-controlled by ciliary muscles

Question 6

Sensetivity

Answer 6

ability to detect the presence of dimly lit objects

Question 7

Acutiy

Answer 7

ability to see the details of objects

Question 8

Accomodation

Answer 8

process by which the lens changes shape to help focus near or far objects on the retina

Question 9

Retina

Answer 9

light sensitive inner surface of eye containing rods and cones plus layers of neurons that process visual info

Question 10

Binocular disparity

Answer 10

the difference in the position of the same image on the 2 retinas
-greater for objects closer than far

Question 11

Scotopic vision

Answer 11

rod mediated vision

• peripheral retina
• black white and grey
• low light

Question 12

Photopic vision

Answer 12

cone mediated vision
-colour and fine detail (high acuity)
-center retina
well lit

Question 13

Optic nerve

Answer 13

carries nerve impulses from eye to brain

Question 14

Blind spot

Answer 14

where optic nerve leaves eye creating a spot where there are no receptor cells

Question 15

Completion

Answer 15

retina extracts info about image and sends it to cortex where the perception of the image is created from partial info

Question 16

Fovea

Answer 16

• central point of retinas made up of only cones
• high acuity vision
• thinning of ganglion cells reduce distortion of light

Question 17

Amacrine and horizontal cells

Answer 17

specialized for lateral communication

Question 18

Retinal ganglion cells

Answer 18

some have on/off receptors fields or are selective to uniform illumination. orientation, motion (simple and complex)

Question 19

Lateral geniculate cells

Answer 19

have receptive fields that are sensitive to one or more….. orientation, motion, direction of motion

Question 20

Saccades

Answer 20

quick eye movements

-if there is a stable retinal image you will see nothing

Question 21

Transduction

Answer 21

conversion of one form of energy to another

Question 22

Visual transduction

Answer 22

light energy to neural signals by visual receptors

Question 23

More cortex is devoted to areas of high ________

Answer 23

acuity

Question 24

Magnocellular layers

Answer 24

input from rods
bottom 2 layers of LGN
responsive to movement

Question 25

Parvocellular layers

Answer 25

input from cones top 4 layers of LGN colour, detail, slow objects

Question 26

Receptive field

Answer 26

the area of the visual field within which it is possible for a visual stimulus to influence the firing of a given neuron

Question 27

Similarities of receptive fields in retinal ganglion, LGN, and lower layer IV of striate cortex

Answer 27

- receptive fields of foveal areas are smaller than those in periphery - circular fields - monocular - center surround organization (excitatory and inhibitory area separated by circular boundary)

Question 28

Diffusely illuminating an entire receptive field will have ______ effect on firing

Answer 28

little

Question 29

Ocular dominance

Answer 29

responds more robustly to stimulation of one eye more than the other