A middle-latency auditory-evoked potential in the rat.
Previous studies have established the presence of a middle-latency auditory-evoked potential that is characterized by a) sleep-state dependence, b) low following frequency (i.e., rapid habituation to repetitive stimulation), and c) blockade by the cholinergic antagonist, scopolamine. A vertex-recorded evoked potential having these characteristics was described in humans at a 50-80 ms latency (termed the P1 or.P50 potential) and in the cat at a 20-25 ms latency (termed wave A). These studies were undertaken to determine if a click stimulus-evoked potential having the same characteristics was present in the intact rat. Vertex and auditory cortex recordings in intact rats studied in a sound-attenuating chamber and exposed to free-field click stimuli showed a) the presence of a vertex recorded potential at a 11-15 ms latency, termed P13, and of an auditory cortex recorded potential at a 7-11 ms latency, termed Pa; b) the P13 was present during waking and paradoxical sleep but absent in slow-wave sleep, while Pa was present in all sleep-wake states; c) the P13 habituated markedly at stimulation rates above 1 Hz while Pa did not; and d) the P13 was blocked by low doses of scopolamine while Pa was not. These studies demonstrate the presence of a P1-like potential in the rat at a 13 +/- 2 ms latency.
Miyazato
H
H
Department of Anatomy, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
Skinner
R D
RD
Reese
N B
NB
Boop
F A
FA
Garcia-Rill
E
E
D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology; D002415:Cats; D004569:Electroencephalography / Q000187:drug effects; D004576:Electromyography / Q000187:drug effects; D005072:Evoked Potentials, Auditory / Q000187:drug effects / Q000502:physiology*; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology; D006185:Habituation, Psychophysiologic / Q000187:drug effects / Q000502:physiology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012601:Scopolamine / Q000494:pharmacology; D012895:Sleep, REM / Q000502:physiology; D014851:Wakefulness / Q000502:physiology
D012601:Scopolamine