Reacquisition deficits in prism adaptation after muscimol microinjection into the ventral premotor cortex of monkeys

Citation
K. Kurata et E. Hoshi, Reacquisition deficits in prism adaptation after muscimol microinjection into the ventral premotor cortex of monkeys, J NEUROPHYS, 81(4), 1999, pp. 1927-1938
Citations number
49
Categorie Soggetti
Neurosciences & Behavoir
Journal title
JOURNAL OF NEUROPHYSIOLOGY
ISSN journal
00223077 → ACNP
Volume
81
Issue
4
Year of publication
1999
Pages
1927 - 1938
Database
ISI
SICI code
0022-3077(199904)81:4<1927:RDIPAA>2.0.ZU;2-L
Abstract
A small amount of muscimol (1 mu l; concentration, 5 mu g/mu l) was injecte d into the ventral and dorsal premotor cortex areas (PMv and PMd, respectiv ely) of monkeys, which then were required to perform a visually guided reac hing task. For the task, the monkeys were required to reach for a target so on after it was presented on a screen. While performing the task, the monke ys' eyes were covered with left 10 degrees, right 10 degrees, or no wedge p risms, for a block of 50-100 trials. Without the prisms, the monkeys reache d the targets accurately. When the prisms were placed, the monkeys initiall y misreached the targets because the prisms displaced the Visual held. Befo re the muscimol injection, the monkeys adapted to the prisms in 10-20 trial s, judging from the horizontal distance between the target location and the point where the monkey touched the screen. After muscimol injection into t he PMv, the monkeys lost the ability to readapt and touched the screen clos er to the location of the targets as seen through the prisms. This deficit was observed at selective target locations, only when the targets were shif ted contralaterally to the injected hemisphere. When muscimol was injected into the PMd, no such deficits were observed. There were no changes in the reaction and movement times induced by muscimol injections in either area. The results suggest that the PMv plays an important role in motor learning, specifically in recalibrating Visual and motor coordinates.