Neuroanatomy 3

Question 1

where do sensory fibres that result from a motor response feed back to?

Answer 1

cerebellum

Question 2

what are basal ganglia

Answer 2

series of grey matter structures key to the initiation and inhibition of movement (are technically nuclei)

Question 3

where is the cerebellum located and what does it control?

Answer 3

posterior cranial fossa

movement

Question 4

how many lobes does the cerebellum have and what are they called?

Answer 4

3 lobes

anterior, posterior, flocculonodular

Question 5

largest lobe of the cerebellum?

Answer 5

posterior lobe

Question 6

what lies immediately superior to the cerebellum?

Answer 6

tentorium cerebelli

Question 7

the cerebellum is attached to the brainstem via _ stalks called….

Answer 7

3

penduncles

Question 8

name the 3 different cerebellar peduncles

Answer 8

superior
inferior
middle (biggest)

Question 9

what fissure divides the anterior and posterior lobes of the cerebellum?

Answer 9

primary fissure

Question 10

what runs through the middle of the whole cerebellum?

Answer 10

superior vermis

Question 11

name the 3 layers of the cerebellum from superficial to deep

Answer 11

molecular (synapses occur here)
purkinje cell
granule cell (most neurons here)

Question 12

main afferents the cerebellum receives?

Answer 12

spinal cord via tracts
cerebral cortex
vestibular apparatus

Question 13

how do afferents reach the cerebellum and convey their information?

Answer 13

enter via the peduncles and project to the granule cell layer

Question 14

where do most of the cerebellum’s efferent axons synapse?

Answer 14

thalamus

Question 15

what carries the only efferent output from the cerebellum

Answer 15

axons of purkinje cells

Question 16

cerebellar hemispheres influence the ____ side of the body

Answer 16

ipsilateral

Question 17

a midline lesion of the cerebellum will cause a problem with…

Answer 17

postural control

Question 18

what will happen if 1 cerebellar hemisphere is disturbed?

Answer 18

coordination is slowed and can show an unsteady gait

Question 19

bilateral cerebellar dysfunction will cause..

Answer 19

slow, slurred speech
ataxia
think DRUNK

Question 20

functions of the basal ganglia

Answer 20

facilitate purposeful movement
inhibit unwanted movements
control posture and muscle tone

Question 21

where are the basal ganglia located?

Answer 21

base of a cerebral hemisphere

Question 22

which part of the basal ganglia appears as 2 stripes

Answer 22

globus pallidus

Question 23

what structure of the basal ganglia runs around the lateral ventricle forming a “horn”

Answer 23

caudate nucleus

Question 24

outer part of the lentiform nucleus is called the ___

Answer 24

putamen

Question 25

what structure is medial to the lentiform nucleus

Answer 25

thalamus

Question 26

how would you be able to identify the substantia nigra in the midbrain

Answer 26

look for 2 black lines

Question 27

which condition causes loss of neurons of the substantia nigra

Answer 27

parkinsons

Question 28

describe the direct pathway controlled by the basal ganglia

Answer 28

neurons in cerebral cortex activated
excitatory activity arrives at putamen
inhibitory neuron activated which makes the next neuron in the thalamus faster (too slow to reach it)
signal reaches the cortex again

Question 29

how can inhibitory neurons actually speed up a signal?

Answer 29

if an inhibitory neuron is activated it projects its inhibitory signal very SLOWLY which means the next neuron is more likely to excite and work faster as it isnt being inhibited much

Question 30

how do the basal ganglia suppress unwanted movement? via what pathway?

Answer 30

slows down excitatory neurons by inhibiting outflow of the thalamus which make the inhibitory neurons work better
via the INDIRECT PATHWAY

Question 31

if someone struggles to initiate movement, what pathway is disturbed

Answer 31

direct pathway

Question 32

damage to the cerebellum on 1 side will affect the contralateral side T or F

Answer 32

F! will always affect ipsilateral side unlike the rest of the brain

Question 33

basal ganglion dysfunction will affect the contralateral side of the brain T or F

Answer 33

T, will always affect the other side

Question 34

main effects of damage to basal ganglia

Answer 34

dyskinesias
change in muscle
NB DO NOT CAUSE PARALYSIS/ATAXIA

Question 35

damage to basal ganglia affects sensory/motor function?

Answer 35

motor only

Question 36

main pathology in huntingtons?

Answer 36

degeneration of basal ganglia and cerebral cortex

Question 37

is parkinsons a problem of the basal ganglia?

Answer 37

yes as it affects the substantia nigra which are a component of the BG