Fig. 3. Analysis of the shunted electric organ discharge (EOD) current. (A) Example illustrating the two effects that contribute to the current measured in the external circuit during maintained switch closure: (i) A slowly decaying current (`offset') that continues even during the silent phases (in the absence of EODs). This component never elicited behavioral responses in the arrangement used in the present study. (ii) The second contribution is from the current that is shunted during the EOD. (B) The two components added linearly within the current range used in the present study. This is illustrated by two recordings of the current in the external circuit, taken at two stages after a maintained switch closure. The first (blue) was taken immediately after the switch was closed and thus when the `offset' was maximal. The second was taken long after the start of switch closure, when the offset had decayed to zero (red). Traces are aligned with respect to the simultaneous recordings of the head—tail EODs, one of which is shown below the two traces (C). Note that the EOD-induced modulation in the absence of the offset is approximately the same as that recorded in the presence of an offset.

Return to article