@article {57620,
	title = {Mechanisms of frequency-specific responses of ω neuron 1 in crickets (Teleogryllus oceanicus): a polysynaptic pathway for song?},
	year = {2001},
	abstract = {<p>In crickets (Teleogryllus oceanicus), the auditory interneuron \&omega; neuron 1 (ON1) responds to sounds over a wide range of frequencies but is most sensitive to the frequency of conspecific songs (4.5 kHz). Response latency is longest for this same frequency. We investigate the mechanisms that might account for the longer latency of ON1 to cricket-like sounds. Intracellular recordings revealed no evidence for appropriately timed postsynaptic inhibition of ON1 that might increase its latency, nor was latency affected by picrotoxin. The onset of excitatory postsynaptic potentials (EPSPs) was delayed for 4.5 kHz stimuli compared with ultrasound stimuli, pointing to a presynaptic locus for the latency difference. When ON1 is stimulated with high frequencies, discrete, apparently unitary EPSPs can be recorded in its dendrite, and these are latency-locked to spikes recorded simultaneously in the auditory nerve. This suggests that input to ON1 from high-frequency-tuned auditory receptor neurons is monosynaptic. In agreement with this, brief ultrasound stimuli evoke a single, short-latency EPSP in ON1. In contrast, the EPSP evoked by a brief 4.5 kHz stimulus consists of an early component, similar in latency to that evoked by ultrasound and possibly evoked by ultrasound-tuned receptors, and a later, dominant component. We interpret the early peak as arising from a monosynaptic afferent pathway and the late peak from a polysynaptic afferent pathway. Multiple-peak EPSPs, with timing similar to those evoked by sound stimuli, were also evoked by electrical stimulation of the auditory nerve.</p>
},
	keywords = {audition, auditory interneuron, cricket, excitatory postsynaptic potential, Insect, monosynaptic pathway, omega neuron 1 (ON1), polysynaptic pathway, song, Teleogryllus oceanicus},
	author = {Faulkes, Z and Gerald S. Pollack}
}
@article {57618,
	title = {Representation of behaviorally relevant sound frequencies by auditory receptors in the cricket teleogryllus oceanicus},
	journal = {Journal of Experimental Biology 1998 Jan;201 (Pt 1):155-63.},
	volume = {201},
	year = {1998},
	pages = {155-163},
	chapter = {155},
	abstract = {<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>
},
	keywords = {acoustic communication, compound action potential, cricket, sensory coding, Teleogryllus oceanicus, ultrasound},
	author = {Gerald S. Pollack and Zen Faulkes}
}
