Bidirectional processing in the olfactory-limbic axis during olfactory behavior.
Field potentials were recorded simultaneously from the olfactory bulb (OB), prepyriform cortex (PPC), entorhinal cortex (EC), and dentate gyrus (DG) of rats trained to respond to appetitively reinforced odors. Preafferent anticipatory events in the beta band (12-35 Hz) suggest transmission from EC to OB before the odorant stimulus. Gamma band (35-120 Hz) power in olfactory regions is significantly reduced during stimulus presentation as compared with high values during preafferent expectation. High coherence of OB and PPC gamma activity during the preodorant control period is interrupted before the stimulus and is followed by increased gamma coherence among OB, EC, and DG. These results suggest that olfactory perceptual processing is bidirectional and covers a wide frequency range.
Graduate Group in Biophysics, University of California, Berkeley, USA. lkay@cns.caltech.edu
L M
LM
Kay
W J
WJ
Freeman
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D001070:Appetitive Behavior / Q000502:physiology; D001143:Arousal / Q000502:physiology; D003216:Conditioning, Operant / Q000502:physiology*; D003344:Cortical Synchronization; D003463:Cues; D018891:Dentate Gyrus / Q000502:physiology; D004525:Efferent Pathways / Q000502:physiology; D018728:Entorhinal Cortex / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology; D008032:Limbic System / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D009812:Odorants; D009833:Olfactory Pathways / Q000502:physiology; D009991:Oscillometry; D051381:Rats; D017207:Rats, Sprague-Dawley; D012201:Reward; D012903:Smell / Q000502:physiology*; D013997:Time Factors