The Journal of Neuroscience, February 15, 1999, 19(4):1508-1516
Neural Coding of Sound Frequency by Cricket Auditory
Receptors
Kazuo
Imaizumi and
Gerald S.
Pollack
Department of Biology, McGill University, Montréal, Quebec
H3A 1B1, Canada
Crickets provide a useful model to study neural processing of sound
frequency. Sound frequency is one parameter that crickets use to
discriminate between conspecific signals and sounds made by predators,
yet little is known about how frequency is represented at the level of
auditory receptors. In this paper, we study the physiological
properties of auditory receptor fibers (ARFs) by making single-unit
recordings in the cricket Teleogryllus oceanicus. Characteristic frequencies (CFs) of ARFs are distributed
discontinuously throughout the range of frequencies that we
investigated (2-40 kHz) and appear to be clustered around three
frequency ranges (
5.5, 10-12, and 
18 kHz). A striking
characteristic of cricket ARFs is the occurrence of additional
sensitivity peaks at frequencies other than CFs. These additional
sensitivity peaks allow crickets to detect sound over a wide frequency
range, although the CFs of ARFs cover only the frequency bands
mentioned above. To the best of our knowledge, this is the first
example of the extension of an animal's hearing range through multiple
sensitivity peaks of auditory receptors.
Key words:
insect hearing; Teleogryllus oceanicus; frequency sensitivity; sound communication; ultrasound; acoustic
startle response; phonotaxis
Copyright © 1999 Society for Neuroscience 0270-6474/99/1941508-09$05.00/0
Previous Article | Next Article
