lecture 5- cerebellum

Question 1

Describe the lobes of the cerebellum.
Which parts of the body are effected by lesions?

Answer 1

anterior lobe, flocculondular lobe and posterior lobe

central lesions–> head and trunk

Peripheral lesions–>limbs

Question 2

What do the cerebellar ponducles do? What are their names and what info goes through them?

Answer 2

Sup, middle and inf poduncles, connect to brain stem, inf/mid sensory info, sup sends out motor

Question 3

Mossy fibers go through 3 different tracts, poduncles and specific region of the cerebellum. Name them and what is the end result?

Answer 3

1) Vestibulocerebellarà ICPàflocculondular lobe, balance and eye movement
2) spinocerebellaràICP, MCPàVermis, motor execution
3) corticocerebellaràMCPàhemisphere, planning

Question 4

Climbing fibers, tract and cells they lead to

Answer 4

Olivary nuclei lead to the purkinje fibers

Question 5

Structure of the cerebellum:
What are the layers and sub layers? What are the functions?

Answer 5

Cortex

• molecularàparallel fibers
• purkinjeàall input goes through here
• granuleàgolgi and glomeruli cells for inhibitions, and granules for excitation(glutamate)

Medulla

Question 6

Circuitry:

All input goes through the purkinjes and they send it to 4 different parts of the cerebellum which each send to a nuclei. Name all

Answer 6

1) flocculondular lobe à lateral vestibular nuclei
2) vermisàfastigial nuclei
3) intermediate hemisphereàinterposed nuclei
4) lateral cerebellar hemisphereàdentate nucleus

Question 7

Describe the two main symptoms of cerebellar lesions

Answer 7

Ipsilateral, tremor when movement initiated

Question 8

Describe hemisphere lesions:
4 symptoms

Answer 8

Tremor, dysmetria, problems alternating movement, gaze dysfunction

Question 9

Vermis lesion main symptom

Answer 9

Cannot balance standing up with EYES OPEN

Question 10

Describe the structure of the Basal Ganglia as well as its main function

Answer 10

Movement and control over skeletal muscles,

Made of Striatum, external/internal segements of globus pollidus, substantia nigra, subthalamic nucleus

Question 11

Describe the two pathways of basal ganglia activation

Answer 11

Direct: inhibit the inhibitor, allows for movement

Indirect: not inhibiting the inhibitor, no movement

Question 12

Diseases of the basal ganglia:
Parkinson
Huntington’s

Wilson

Tourette

Answer 12

P: low dopamine due to loss of nerves in substantia nigra, resting tremor, balance loss, dementia

H: chorea, slow movement, degeneration of GABA

W: copper in liver, liver failure, chorea

T: motor and verbal tics, ADHD

Question 13

Describe the visual pathway and the pupillary light reflex

Question 14

Describe the input , region of thalamus and output of fibers going (8 things)

Answer 14

• Sensory from limbsàVPLàsomatosensory cortex
• Sensory from faceàVPMàsomatosensory cortex
• Motor info from BG and cerebellumàVA/VLàmotor cortex
• Optic tractàlateral geniculate bodyàoccipital lobe
• inferior colliculusàmedial geniculate bodyàauditory cortex
• mamillary nucleusàANàcingulate gyrus
• medial dorsal nucleusà memory
• pulvinaràintegration of somatic, visual and auditory input

Question 15

Hypothalamus:

What are the functions of these regions and what do lesions cause?
Lateral hypothalamic, ventromedial, suprachiasmtic, mammillary body, arcuate, anterior region, post region, preoptic region, dosomedial

Answer 15

Lateral: feeding, starvation

Ventromedial: satiety, obesity

Suprachiasmatic: circadian rhythm, lose sleep

Supraptic/paraventricular: synthesize ADH, diabetes insephalas

Mammillary: input from hippocampus

Arcuate: inhibitory factors

Anterior region: temp regulation, hyperthermia

Post region: temp regulation, inability to thermoregulate

Preoptic: release of gonatotrophic hormones, before pub: arrested sexual development
after pub: impotence

Dorsomedial: limbic systemà RAMPAGE