Effects of telencephalic lesions on the gill cover response of siamese fighting fish

Abstract

Gill cover extension, a component of the fighting pattern of Siamese fighting fish, Betta splendens, was observed in 7 telencephalic-lesioned and 7 sham-operated fish during exposure to mirror image and live Betta stimuli. The conspecific stimulus elicited more frequent and longer duration gill cover (operculum) responses than the mirror stimulus. Lesioning decreased the frequency of gill cover responses to both stimuli. The mean duration of the gill cover response was not affected by lesioning and, unlike response rate, did not decrease (habituate) with repeated stimulus presentation. Lesioning reduced the efficiency of food retrieval and tended to reduce activity level. Behavioral changes may be related to the extent of the lesion. Results are discussed in relation to current hypotheses concerning forebrain function.