Lecture 22

Question 1

cerebellar disorders

Answer 1

• cerebellum is the area of brain that sits behind brainstem
• aids in providing smooth, coordinated body movements (critical for controlling fine and voluntary movements)
• see disruption and degeneration due to anomalies, alcohol abuse, nutritional deficiencies etc.
• see changes in movement

Question 2

Key features of cerebellar disorders

Answer 2

• balance deficits
• increased amplitude of sway
• increased frequency of sway
• greatest differences with eyes closed
• larger instability in cerebellar lesions involving the anterior lobe

Question 3

individuals with cerebellar ataxia are seen to have ____ when conducting a standing task on 2 legs, eyes closed on foam support

Answer 3

increased trunk angle and trunk velocity
patients also have shorter stance durations as well

Question 4

dynamic control of balance in CD

Answer 4

much larger amplitudes of responses
lack of a single robust response
oscillatory responses with undershooting and overshooting
instability persists for long periods of time after initial perturbation

Question 5

individuals with CD require _____

Answer 5

corrective responses in antagonist muscles due to overshooting

Question 6

Cerebellar patients are unable to ____ to

Answer 6

scale muscle responses and torques, expected perturbation amplitude
Horak and Diener 1994

Question 7

APAs to voluntary movements in those with CD are ____

Answer 7

frequently absent or delayed in their timing
seen during rise to toes task conducted by Dichgans et. al. in 1992