Modulation of neuronal activities by iontophoretically applied catecholamines and acetylcholine in the primate motor cortex during a visual reaction-time task.
Single neuronal activities in the primate motor cortex were modulated by iontophoretically applied acetylcholine (ACh), noradrenaline (NA) or dopamine (DA) while monkeys were performing a visual reaction-time. task. ACh caused general increases of the discharge activities of both the background baseline and the task-related activity peaks, whereas NA caused decreases mainly of the baseline. DA caused activity increases in half of the tested neurons, and decreases in 25% of the neurons. NA modulated the firing rate to enhance the signal-to-noise ratio of the related activities. ACh and DA, by contrast, subserved to enhance the synaptic transmission in the motor cortex.
Matsumura
M
M
Department of Neurophysiology, Primate Research Institute, Kyoto University, Aichi, Japan.
Sawaguchi
T
T
Kubota
K
K
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002395:Catecholamines / Q000494:pharmacology*; D004567:Electrodes, Implanted; D007478:Iontophoresis; D008251:Macaca; D009044:Motor Cortex / Q000033:anatomy & histology / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects*; D010775:Photic Stimulation; D011930:Reaction Time / Q000187:drug effects*
D002395:Catecholamines; D000109:Acetylcholine