Submillisecond synchronization of fast electrical oscillations in neocortex.
Fast electrical oscillations (FOs; >200 Hz) in the sensory neocortex can be recorded in a variety of species, including humans, and may reflect extremely fast integration of sensory information. This report demonstrates that, in the whisker representation of rat cortex, multivibrissa stimulation produces propagating FO field potential patterns and time-locked unit activity that are sensitive to submillisecond delays in interstimulus intervals. We propose that FOs may be produced by synchronized population spikes and their subthreshold sequelas in cortical pyramidal cells. FOs serve to accurately mark stimulus onset as a phase-encoded excitatory signal, producing phase-sensitive interactions that, in the context of exploratory whisking, may extract features of an object under exploration.
Barth
Daniel S
DS
Department of Psychology, University of Colorado, Boulder, Colorado 80309-0345, USA. dbarth@psych.colorado.edu
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D001931:Brain Mapping; D016000:Cluster Analysis; D003344:Cortical Synchronization; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D008297:Male; D008839:Microelectrodes; D019579:Neocortex / Q000502:physiology*; D010812:Physical Stimulation / Q000295:instrumentation / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology; D014738:Vibrissae / Q000294:innervation / Q000502:physiology