Figure 9.

Ambulation score (the number of times fish moved from one imaginary segment to another on a 3×3 grid) is significantly affected by all stimuli except the presentation of the single zebrafish image. Mean ± S.E.M. are shown. Sample sizes (n) are indicated in the text. White bars represent performance during the pre-stimulus (habituation) period, black bars represent the stimulus period performance and grey bars the post-stimulus period performance. The stimulus type employed is indicated above the bar graphs. Note that among the stimuli that had significant effect on the ambulation score the needle fish was the only one that increased the response while the others all decreased it.