Intrinsic and circuit properties favor coincidence detection for decoding oscillatory input.
In the insect olfactory system the antennal lobe generates oscillatory synchronization of its output as a framework for coincidence detection by its target, the mushroom body (MB). The intrinsic neurons of the MB (Kenyon cells, KCs) are thus a good model system in which to investigate the functional relevance of oscillations and neural synchronization. We combine electrophysiological and modeling approaches to examine how intrinsic and circuit properties might contribute to the preference of KCs for coincident input and how their decoding of olfactory information is affected by the absence of oscillatory synchronization in their input. We show that voltage-dependent subthreshold properties of KCs bring about a supralinear summation of their inputs, favoring responses to coincident EPSPs. Abolishing oscillatory synchronization weakens the preference of KCs for coincident input and causes a large reduction in their odor specificity. Finally, we find that a decoding strategy that is based on coincidence detection enhances both noise tolerance and input discriminability by KCs.
Perez-Orive
Javier
J
Computation and Neural Systems, Division of Biology, California Institute of Technology, Pasadena, California 91125, USA.
Bazhenov
Maxim
M
Laurent
Gilles
G
D000200:Action Potentials; D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D003712:Dendrites / Q000502:physiology; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D006110:Grasshoppers / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D024521:Mushroom Bodies / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D009812:Odorants; D012679:Sense Organs / Q000502:physiology*; D012903:Smell / Q000502:physiology*; D013997:Time Factors