Function of Cerebellum-Basal Ganglia

Question 1

What does the prism-adaptation experiment demonstrate?

Answer 1

The ability of the cerebellum to accommodate to unexpected motor-control outcomes

Question 2

What fibers do gamma motor neurons innervate?

Answer 2

Intrafusal spindle fibers

Question 3

Dopamine from the substantia nigra stimulates __________ in the ____________ in response to disappointment (when the outcome does not match your prediction).

Answer 3

reconnections; striatum

this is the nigrostriatal pathway

Question 4

Lesions of the cerebellar vermis produce what symptoms?

Answer 4

Discoordination of the trunk, posture, and gait

Question 5

Lateral lesions of the cerebellum lead to ___________.

Answer 5

discoordination of the ipsilateral arm

Question 6

Both basal ganglia disorders and cerebellar disorders present with tremor, but there is a key difference. What is it?

Answer 6

Cerebellar tremors occur with action, while basal ganglia tremors occur at rest

Question 7

Hypermetria and hypometria are ______________.

Answer 7

overshooting or undershooting an aimed-at target

Question 8

What gait characterizes Parkinson’s?

Answer 8

A stooped gait with small, shuffling steps

Question 9

What parts of the brain send information to the inferior olivary nucleus?

Answer 9

The parietal lobes. If the visual and proprioceptive information is what the brain expects, then the ION will not be stimulated. It will be stimulated if there is an unexpected result.

Question 10

What pathway mediates the reward system?

Answer 10

The striosome projects to the substantia nigra / VTA and conveys the current state of the cortex. In response to unexpected reward, the striosome stimulates the SN/VTA and causes it to release dopamine, thus remembering the cortical state that produced that behavior.

Question 11

Positive pronator drift can indicate three possible disorders: ________________.

Answer 11

ipsilateral cerebellar disorders
contralateral parietal disorders
contralateral pyramidal tract disorders

Question 12

Saying “LaPaKa” tests which cranial nerves?

Answer 12

La: 12
Pa: 7
Ka: 10

Question 13

Neuropathic gaits are characterized by weak ____________.

Answer 13

dorsiflexion

Question 14

Ataxic gaits are characterized by ____________.

Answer 14

wide, staggering, and clumsy

Question 15

Slamming the foot down is characteristic of what type of gait?

Answer 15

Sensory gaits

Question 16

A key point of cerebellar damages is that small lesions ___________.

Answer 16

have almost no effect; lesions of the SCP of DCN, however, have a huge effect

Question 17

What is paratonia?

Answer 17

When the patient actively opposes any passive movement, despite instructions to relax