Figure 4.
Responsiveness to Electric Shocks
(A) Schematic of a fish's orientation in the electric field. The orientation angle is calculated between arm direction and fish heading direction. White arrows show the direction of the electric field. Black lines indicate the positions of the electrodes.
(B) A radial histogram of the probabilities of shock-triggered swim bouts (i.e., responses to shocks) plotted against the fish's orientation in the electric field (bin size 9°).
(C) Comparison of the bout amplitudes between different orientations in the electric field (2-sample t test). Bout amplitude is calculated as speed integrated over the duration of a bout. “Aligned” bouts include anode- and cathode-facing orientations; “misaligned” bouts include into-arm- and out-of-arm-facing orientations.
(D) Variety of amplitudes and onsets of individual shock-triggered swim bouts. Each curve shows the speed during an individual bout (N = 4,091 bouts).
(E) Response types identified by hierarchical cluster analysis: low amplitude with early onset (LAearly, N = 1,968 bouts), low amplitude with late onset (LAlate, N = 1,995 bouts), and high-amplitude responses (HA, N = 128 bouts). Left: radial histogram of how many bouts of a certain type occur plotted against the fish's orientation in the electric field (bin size 9°). Right: speed over time after the shock onset. Y axes are the same as in (D).
(F) Comparison of OC (left) and EF (right) scores in a 5-min time window after a shock-triggered bout between different response types (Mann-Whitney test). Each dot represents an OC or EF score after an individual shock-triggered bout. Horizontal lines indicate sample means. Bouts were obtained from the experiments with 27 fish.