01824nas a2200205   4500008004100000245012200041210006900163300001200232490000800244520115400252653002701406653003001433653001201463653001901475653002701494653001501521100002401536700001701560856004101577       1998                        eng d00aRepresentation of behaviorally relevant sound frequencies by auditory receptors in the cricket teleogryllus oceanicus0 aRepresentation of behaviorally relevant sound frequencies by aud  a155-1630 v2013 a<p>Teleogryllus oceanicus is particularly sensitive to two ranges of sound frequency, one corresponding to intraspecific acoustical signals (4-5 kHz) and the other to the echolocation cries of bats (25-50 kHz). We recorded summed responses of the auditory nerve to stimuli in these two ranges. Nerve responses consist of trains of compound action potentials (CAPs), each produced by the summed activity of a number of receptor neurons. The amplitude of the CAP is up to four times larger for stimuli at 4.5 kHz than for stimuli at 30 kHz, suggesting either that the extracellular spikes produced by receptors that respond to 4.5 kHz are larger than those that respond to 30 kHz, or that receptors fire more synchronously in response to stimulation at 4.5 kHz, or that more receptors respond to stimulation at 4.5 kHz. Neither unit spike amplitude nor conduction velocity (which is expected to vary with spike amplitude) differs for the two frequencies, and the responses to 4.5 kHz are not produced by more tightly synchronized receptor populations, as judged by CAP breadth. We conclude that more receptors respond to 4. 5 kHz than to 30 kHz.</p>
10aacoustic communication10acompound action potential10acricket10asensory coding10aTeleogryllus oceanicus10aultrasound1 aPollack, Gerald, S.1 aFaulkes, Zen  uhttps://bio.acousti.ca/it/node/5761802304nas a2200181   4500008004100000245008200041210006900123520165300192653002701845653001601872653001201888653002401900653002001924100002501944700001401969700001901983856012002002       2011                        eng d00aHigh background noise shapes selective auditory filters in a tropical cricket0 aHigh background noise shapes selective auditory filters in a tro3 a<p>Because of call frequency overlap and masking interference, the airborne sound channel represents a limited resource for communication in a species-rich cricket community like the tropical rainforest. Here we studied the frequency tuning of an auditory neuron mediating phonotaxis in the rainforest cricket Paroecanthus podagrosus, suffering from strong competition, in comparison with the same homologous neuron in two species of European field crickets, where such competition does not exist. As predicted, the rainforest species exhibited a more selective tuning compared with the European counterparts. The filter reduced background nocturnal noise levels by 26 dB, compared with only 16 and 10 dB in the two European species. We also quantified the performance of the sensory filter under the different filter regimes by examining the representation of the species-specific amplitude modulation of the male calling song, when embedded in background noise. Again, the filter of the rainforest cricket performed significantly better in terms of representing this important signal parameter. The neuronal representation of the calling song pattern within receivers was maintained for a wide range of signal-to-noise ratios because of the more sharply tuned sensory system and selective attention mechanisms. Finally, the rainforest cricket also showed an almost perfect match between the filter for sensitivity and the peripheral filter for directional hearing, in contrast to its European counterparts. We discuss the consequences of these adaptations for intraspecific acoustic communication and reproductive isolation between species.</p>
10aacoustic communication10acompetition10acricket10adirectional hearing10aMatched filters1 aSchmidt, Arne, K. D.1 aRiede, K.1 aRömer, Heiner  uhttp://jeb.biologists.org/cgi/doi/10.1242/jeb.053819https://syndication.highwire.org/content/doi/10.1242/jeb.053819