neuroanatomy 3

Question 1

lobes of the cerebellum

Answer 1

anterior, posterior and flocculonodular

Question 2

how is the cerebellum attatched to the brainstem

Answer 2

By three stalks (of white matter) called peduncles - middle cerebellar, surperior cerebellar and inferior cerebellar pudencles

Question 3

middle of the cerebellum called?

Answer 3

vermis - middle pinched area ‘worm like’

Question 4

what is the arbor vitae

Answer 4

white matter in the cerebellum - tree of life

some deep grey matter can be seen in it

Question 5

how many deep nuclei are in the cerebellum

Answer 5

4

dentate nucleus is the deepest

Question 6

three layers of teh cerebellar cortex

Answer 6

molecular layer (outer), purkinje layer(middle), granule cell layer (inner)

Question 7

where does afferent info mainly project to

Answer 7

granule cell layer

Question 8

where does the output info from cerebellum arise from

Answer 8

only output is via the axons of purkinje cells which synapse on neurons of deep cerebellar nuclei, so it conytributes to the coordination of all the motor tracts (coticospinal, vestibulospinal, rubrospinal)

Question 9

where do efferent axons from the cerebellar synapse

Answer 9

cross the midline and synapse at the thalamus, the thalamus in turn sends them to the motor cortex

Question 10

what do the cerebellar hemispheres do and what signs would a lesion cause?

Answer 10

influence the ipsilateral side of the bod, so lesions lead to ipsilateral signs (contrast to lesions of sensory/motor cortex)
unilateral hemispheric lesion - disturbance in coordination of limbs. can result in intention tremor and unstrady gait in the absence of weakness or sensory loss
bilateral dysfunction - slowed, slurred speech, bilateral incoordination of the arms and a staggering, wide based gait (cerebellar ataxia) (alcohol causes this)

Question 11

what would a midline lesion in the cerebellum cause

Answer 11

disturbance if postural control. patient will fall when standing or sitting despite preserved limb coordination

Question 12

what is the midline division of the cerebellum

Answer 12

spinocerebellum

Question 13

what are the lateral divisions of the cerebellum called

Answer 13

pontocerebellum

Question 14

what is the third division of the cerebellum called

Answer 14

vestibulocerebellum

Question 15

list the functions of the basal ganglia

Answer 15

facilitate purpousful movement
inhibit unwanted movements
role in posture and muscle tone

Question 16

where is the basal ganglia

Answer 16

base of cerebral hemispheres - grey matter structure

Question 17

what makes up the basal ganglia

Answer 17

caudate nucleus, putamen, globus pallidus, subthalamic nucleus, substantia nigra

Question 18

what makes up teh striatum

Answer 18

caudate nucleus and putamen

Question 19

what makes up the corpus striatum

Answer 19

caudate nucleus, putamen and the globus pallidus

Question 20

what makes up the lenticular nucleus

Answer 20

putamen and golbus pallidus

Question 21

from what structure of the basal ganglia are cells lost in parkinsons

Answer 21

substantia nigra (degeneration of dopaminergic neurons of the substantia nigra)

Question 22

main role of basal ganglia and indirct pathway

Answer 22

accentuate movements you want to occur - enhances outflow of thalamus. indirect pathway - dampens movements you dont want to occur

Question 23

unilateral lesion in the basal ganglia - ipsilateral side affected or contralateral?

Answer 23

conyralateral side

Question 24

what do lesions in the basal ganglia cause

Answer 24

changes in muscle tone, dyskinesia (abnormal involuntary movements including - tremor, chorea, myoclonus)

Question 25

pathology of huntingtons disease and signs

Answer 25

AD. progressive degeneration of the basal ganglia and cerebral cortex. signs include chorea and progressive dementia