RT Journal Article
SR Electronic
T1 Saccadic Dysmetria and Adaptation after Lesions of the Cerebellar Cortex
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 10931
OP 10939
DO 10.1523/JNEUROSCI.19-24-10931.1999
VO 19
IS 24
A1 Barash, Shabtai
A1 Melikyan, Armenuhi
A1 Sivakov, Alexey
A1 Zhang, Mingsha
A1 Glickstein, Mitchell
A1 Thier, Peter
YR 1999
UL http://www.jneurosci.org/content/19/24/10931.abstract
AB We studied the effects of small lesions of the oculomotor vermis of the cerebellar cortex on the ability of monkeys to execute and adapt saccadic eye movements. For saccades in one horizontal direction, the lesions led to an initial gross hypometria and a permanent abolition of the capacity for rapid adaptation. Mean saccade amplitude recovered from the initial hypometria, although variability remained high. A series of hundreds of repetitive saccades in the same direction resulted in gradual decrement of amplitude. Saccades in other directions were less strongly affected by the lesions. We suggest the following. (1) The cerebellar cortex is constantly recalibrating the saccadic system, thus compensating for rapid biomechanical changes such as might be caused by muscle fatigue. (2) A mechanism capable of slow recovery from dysmetria is revealed despite the permanent absence of rapid adaptation.