ELECTROPHYSIOLOGICAL STUDY OF LATERAL DISCRIMINATION IN OLFACTION

Twenty seven rabbits were submitted in acute experiments to bilateral olfactory stimulation. E.O.G. on both side and glomerular layer response on one side were simultaneously recorded. When both stimuli were presented at different onset times and equal concentrations, the glomerular response fell to 50 per cent of its normal amplitude when the contralateral stimulation was given 3 msec before the homolateral one. When both stimuli were adjusted for maximum temporal inhibition, the inhibition of the homolateral glomerular response increased proportionally to the concentration of the heterolateral stimulus provided it be lower than the homolateral one. For equal or superior heterolateral concentration, the inhibition reached a plateau at 50 per cent. This interbulbar inhibition was suppressed by section of the anterior commissure. It was unaffected by a retrocommissural bilateral transection of the forebrain. Some discrepancies among available data about olfactory localization are discussed and tentatively elucidated. © 1969.