TitleElectrophysiological evidence of synaptic interactions within chemosensory sensilla of scorpion pectines
Publication TypeJournal Article
Year of Publication1997
AuthorsGaffin, DD, Brownell, P
JournalJournal of Comparative Physiology a-Sensory Neural and Behavioral Physiology
Type of ArticleJournal Article

The pectines of scorpions are ventral bilateral appendages supporting 10(4)-10(5) chemosensory sensilla called pegs. Each peg contains 10-18 sensory neurons, some of which show ultrastructural evidence of axoaxonic synapses with other sensory neurons in the same sensillum. In extracellular recordings from single-peg sensilla, individual sensory units can be distinguished by impulse waveform and firing frequency. Cross-correlation analysis of impulse activity showed that at least two of these units, types 'A1' and 'A2', are inhibited during the 100-ms period immediately following activity of a third unit, type 'B'. This interaction between sensory units in a single sensillum also occurs in surgically isolated pectines, indicating that it does not involve efferent feedback from the central nervous system. Other sensillar neurons appear to have excitatory interactions. Thus, in scorpion pectine, chemosensory information undergoes some form of processing within individual sensilla prior to its relay to the CNS, making this an unusually accessible preparation for study of first-order chemosensory processing events.

URL<Go to ISI>://WOS:A1997XU87300012