Kramer, Bernd and Weymann, Dieter (1987) A microprocessor system for the digital synthesis of pulsed and continuous discharges of electric fish (or animal vocalization S). Behavioural Brain Research 23 (8), pp. 167-174.
Traditionally, the sensitivity of electric fish to electric stimuli has been investigated using a variety of electronically generated signal functions, for example sine, square, and sawtooth waves (both continuous and pulsed). None of these resemble the speciesor sex-specific electric organ discharges (EODs) of fish. Therefore, EODs recorded on magnetic tape were used in open-loop playback experiments. However, as shown in the present paper, the waveforms of EODs reproduced from magnetic tape are distorted, and cannot be manipulated with speed and accuracy as to frequency or pulse repetition rate by feedback from the experiment. Good EOD imitations are generated by our microprocessor-based system for the digital synthesis of EODs which is controlled by a small 'personal computer'. Digitized EOD samples edited by computer are output by the fast digital-to-analogue converter of the microprocessor system. This system was devised for the synthesis of pulse-type (discontinuous) and wave type (continuous) EODs with continuous, on-line frequency and amplitude control. The rate of digital synthesis is 500 kHz in pulse-type EODs, and 250-500 kHz in wave type EODs at 0.06-0.24 Hz frequency resolution, depending on the repetition frequency ofthe synthesized wave EOD. The present paper describes the steps in EOD synthesis, and indicates some applications which benefit from the playback of high-fidelity imitations of natural EODs at amplitudes and frequencies selected by the experimenter, or automatically controlled by feedback from the experiment in closed-loop applications.
|Institutions:||Biology, Preclinical Medicine > Institut für Zoologie > Verhaltensbiologie und Verhaltensphysiologie (Prof. Dr. Bernd Kramer)|
|Keywords:||Animal communication signal; Animal orientation signal; Electric organ discharge; Microprocessor; Digital synthesis; Analogue-to-digital conversion; Digital-to-analogue conversion; Signal waveform|
|Subjects:||600 Technology > 600 Technology (Applied sciences)|
500 Science > 570 Life sciences
500 Science > 590 Zoological sciences
|Refereed:||Yes, this version has been refereed|
|Created at the University of Regensburg:||Yes|
|Deposited On:||03 Jul 2008 12:19|
|Last Modified:||09 Jan 2013 07:33|