27: Cerebellum

Question 1

Cerebellum functions

Answer 1

Coordinates somatic motor activity, maintains equilibrium, assures smooth and orderly muscular contraction sequences

Question 2

How is the cerebellum a “rheostat”?

Answer 2

Adjusts output of motor systems

Question 3

Mnemonic for the fibers running through the inferior cerebellar peduncles

Answer 3

DDT Always Ruins Olives

Question 4

Seven tracts through the inferior cerebellar peduncles

Answer 4

1. DSCT
2. Direct Arcuate Fibers
3. Trigeminocerebellar Tract
4. Arcuocerebellar Fibers
5. Reticulocerebellar Fibers
6. Olivocerebellar Fibers
7. Central Tegmental Fasciculus

Question 5

Corticopontine fibers: origin and termination

Answer 5

Motor cortex -> ipsilateral pontine nuclei

Question 6

Three tracts through the superior cerebellar peduncle

Answer 6

1. VSCT
2. Trigeminocerebellar tract
3. Tectocerebellar fibers

Question 7

What do tectocerebellar fibers convey?

Answer 7

Visual and auditory info

Question 8

Generally, what do cerebellar lesions cause?

Answer 8

Ipsilateral defects bc of extensive crossing and recrossing of tracts

Question 9

Ataxia

Answer 9

Broad-based staggering gate

Question 10

Korsakoff syndrome

Answer 10

Cerebellar ataxia and memory impairment due to EtOH abuse

Question 11

Sensory ataxia

Answer 11

Caused by loss of sensory input, different from cerebellar ataxia

Question 12

Dysdiadochokinseia

Answer 12

Inability to perform rapidly alternating movements (ex: quick pronation and supination of the hand)

Question 13

Dysmetria

Answer 13

“Missing the mark” during tests, such as touching finger to nose to finger

Question 14

Action (intention) tremor

Answer 14

Tremor that worsens with voluntary movements

Question 15

Decomposition of movement

Answer 15

Breakdown of fluid, multi-joint patterns of movement, giving a robotic appearance