Vergence eye movement signals in the cerebellar dorsal vermis.
We examined simple-spike activity of Purkinje cells (P-cells) that responded during a search task which required both vergence- and frontal-pursuit. Of a total of 100 responding P-cells, 16% discharged only for frontal-pursuit, 43% only for vergence-pursuit, and 41% for both. Thus, the majority of vermal pursuit P-cells modulated their activity during vergence-pursuit. These P-cells also discharged for vergence eye movements induced by step target-motion in-depth. The majority of vergence related P-cells carried convergence signals with both eye velocity and position sensitivities, and they discharged before the onset of convergence eye movements. Muscimol infusion into the sites where convergence P-cells were recorded resulted in a reduction of peak convergence eye velocity, of initial convergence eye acceleration, and of frontal-pursuit eye velocity. These results suggest specific involvement of the dorsal vermis in vergence eye movements.
Nitta
Takuya
T
Department of Physiology, Hokkaido University School of Medicine, Sapporo 060-8638, Japan.
Akao
Teppei
T
Kurkin
Sergei
S
Fukushima
Kikuro
K
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D002531:Cerebellum / Q000033:anatomy & histology* / Q000187:drug effects / Q000502:physiology; D003290:Convergence, Ocular / Q000502:physiology*; D009118:Muscimol / Q000494:pharmacology; D011689:Purkinje Cells / Q000166:cytology / Q000378:metabolism
D009118:Muscimol