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Fig. 6. Low-frequency (LF) electrical stimuli that recruit the ampullary
electroreceptors more and the tuberous electroreceptors less than
high-frequency stimuli (HF) are more efficient in eliciting post-pause
responses. Means + S.E.M. of efficiency,
(100), 100 electric organ
discharges (EODs) after a pause were determined for three different types of
stimulus: the mechanical stimulus (`Mech'; shown in
Fig. 3), a low-frequency
stimulus (a single cycle of a 2 Hz or a 10 Hz sine wave, selected with equal
likelihood) and a high-frequency electrical stimulus (one cycle of a 1 kHz
sine wave). LF and HF electrical stimuli had the same intensity (2.35 mV
cm-1 peak-to-peak). Data were obtained from 171 pauses in two fish
(fish gc1, dark grey columns, 26, 35 and 20 measurements for mechanosensory,
LF and HF stimuli, respectively; fish gc2, light grey columns, 30 measurements
for each stimulus type).