Lecture 1

Question 1

what are the three stimuli the visual system needs to recognise

Answer 1

food
predator
mate

Question 2

the right hemifield activates the

Answer 2

left part of the brain

Question 3

what part of the brain processes visual info

Answer 3

lateral geniculate nucleus

Question 4

what are the two main pathways in the visual system

Answer 4

dorsal - where - posterior parietal

ventral - what - inferior temporal

Question 5

OFF cells express

Answer 5

inotropic glutamate receptors

Question 6

ON cells express

Answer 6

metabotropic glutamate receptors

Question 7

describe taste transduction

Answer 7

the taste buds detect stimulus - pass it on to solitary nucleus of brainstem - goes to ventral posterior medial nucleus - goes to insult and parietal cortex

Question 8

why is sound important

Answer 8

communication 
emotion 
recognition different sounds
topographic view auditory 
survival

Question 9

what features of sound need encoding

Answer 9

frequency
intensity
onset
duration - ear has to remain sensitive without fatigue

Question 10

what is the human equivalent of the mushroom body

Answer 10

piniform complex

Question 11

what is the human equivalent of the lateral horn

Answer 11

amygdala

Question 12

what is the amygdala for

Answer 12

innate behaviour

Question 13

chambers of cochlea

Answer 13

scala vestiboli - top
scala media - middle with organ of corti
scata tympani - bottom

Question 14

what is in the Scala vestibule and the Scala tympani

Answer 14

perilymph
low potassium
normal calcium

Question 15

what is in the scala media

Answer 15

endolymph
high potassium
low calcium

Question 16

wheat is the organ of corti

Answer 16

tectorial membrane

Question 17

at rest what is happening on the general hair cell

Answer 17

slight tension at tip links
resting MET current
large electrical gradient for potassium entry

Question 18

what happens during excitation

Answer 18

large deflection of hair bundle 
maximal tip link tension 
large MET current 
fully depolarises hair cell (-30mV)
rapid train of action potentials

Question 19

what happens during inhibition

Answer 19

large deflection of hair bundle in opposite direction
minimal tip link tension
no MET current
fully HYPERpolarises hair cell below resting potential (-65mV)
no or very few action potentials

Question 20

outer hair cells

Answer 20

V shaped hair bundle
majority of nerve are efferent fibres
prestin
function is to amplify the cochlea

Question 21

where do the type I afferent neurones go

Answer 21

IHC (95% of all afferents)

Question 22

type II afferent go

Answer 22

OHC (5%)

Question 23

LOC efferent

Answer 23

to IHC

Question 24

MOC efferent

Answer 24

OHC

Question 25

what is the lateral geniculate nucleus

Answer 25

6 layers 
macular input (1 eye)
layers alternate input from each eye 
organised retinotopically 
located deep so not much known

Question 26

what is the thralamic relay station

Answer 26

ganglion axons make 1:1 connections with LGN

Question 27

do the ventral and dorsal pathways interact

Answer 27

yes

Question 28

as the hierarchical model of object recognition goes down

Answer 28

decreases in stimulus complexity

Question 29

where are the simple cells located

Answer 29

layers 4+6 responds to bar in certain orientations presented in centre of receptive field

Question 30

where are complex cells located

Answer 30

layers 2,3+5 responds to bar in certain orientations anywhere in the receptive field

Question 31

what are the receptive fields downstream of V1

Answer 31

increase in complexity

receptive fields increase in size