Habituation of fright and arousal responses in the teleosts Carassius auratus and Rutilus rutilus.

The habituation of fright and arousal responses of goldfish (Carassius auratus) and roach (Rutilus rutilus) to the repeated operation of a plunger in the water was studied. The early response was of fright, which habituated, and the response characteristic of arousal appeared, which then habituated as well. Longer intervals between stimuli required more presentations of the stimulus for habituation to occur in goldfish. Roach required more presentations of the stimulus than goldfish for the responses to habituate, and telencephalic ablation severely impaired habituation of arousal, though not fright responses, in this species. The results are discussed in relation to recent work on arousal, habituation, and telencephalic function in fish.