Strong single-fiber sensory inputs to olfactory cortex: implications for olfactory coding.
Olfactory information is first encoded in a combinatorial fashion by olfactory bulb glomeruli, which individually represent distinct chemical features of odors. This information is then transmitted to piriform (olfactory) cortex, via axons of olfactory bulb mitral and tufted (M/T) cells, where it is presumed to form the odor percept. However, mechanisms governing the integration of sensory information in mammalian olfactory cortex are unclear. Here we show that single M/T cells can make powerful connections with cortical pyramidal cells, and coincident input from few M/T cells is sufficient to elicit spike output. These findings suggest that odor coding is broad and distributed in olfactory cortex.
Franks
Kevin M
KM
Department of Neuroscience, University of California, San Diego, School of Medicine, La Jolla, California 92093, USA. kf2189@columbia.edu
Isaacson
Jeffry S
JS
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D002540:Cerebral Cortex / Q000166:cytology*; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D018756:GABA Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D009412:Nerve Fibers / Q000502:physiology* / Q000528:radiation effects; D009812:Odorants; D009831:Olfactory Mucosa / Q000166:cytology / Q000502:physiology; D009833:Olfactory Pathways / Q000187:drug effects / Q000502:physiology*; D018034:Olfactory Receptor Neurons / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques / Q000379:methods; D010852:Picrotoxin / Q000494:pharmacology; D017966:Pyramidal Cells / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D013324:Strontium / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
D000779:Anesthetics, Local; D018756:GABA Antagonists; D010852:Picrotoxin; D013324:Strontium; D013779:Tetrodotoxin