HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 561/1/205    most recent jphysiol.2004.075325v1 Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Staba, R. J Articles by Barth, D. S Search for Related Content PubMed PubMed Citation Articles by Staba, R. J Articles by Barth, D. S

¹ Department of Psychology, University of Colorado, Boulder, CO 80309-0345, USA

Fast electrical oscillations (FOs; > 200 Hz), superimposed on vibrissa-evoked slow potentials, may support rapid sensory integration in neocortex. Yet, while it is well established that the positive/negative (P1/N1) slow wave of the somatosensory evoked potential primarily reflects sequential activation of supragranular and infragranular pyramidal cells mediated chiefly via excitatory chemical synaptic pathways, little is known about the generation of FOs. In this study, laminar current source–density analysis and principal component analysis indicated that FOs are generated by two dipolar current sources situated in the supra- and infragranular layers, similar in laminar location to the two current dipoles associated with the slow wave. However, exogenous GABA application reversibly abolished the N1 slow wave, leaving the P1 intact, while the FO was unaffected by GABA. Furthermore, reductions in both supra- and infragranular cortical unit discharge during application of GABA suggests that FO generation is not dependent on the same intracortical synaptic circuits that are associated with the N1 slow wave. These data suggest a marked functional dissociation between neural mechanisms underlying the slow and fast components of the vibrissa-evoked response.

(Received 7 September 2004; accepted after revision 1 October 2004; first published online 1 October 2004)
Corresponding author R. J. Staba: Department of Psychology, University of Colorado, Boulder, CO 80309-0345, USA. Email: staba{at}psych.colorado.edu

This article has been cited by other articles:

				K. M. Rodgers, A. M. Benison, and D. S. Barth Two-Dimensional Coincidence Detection in the Vibrissa/Barrel Field J Neurophysiol, October 1, 2006; 96(4): 1981 - 1990. [Abstract] [Full Text] [PDF]