The objective of the series of experiments proposed here is to assess the visual capacities of goldfish that have undergone lesions and regeneration in the retinotectal connections of the visual system. The results will provide an understanding of the functional capacities of the regenerated visual connections. In addition, some of the experiments will provide information about the function of certain brain structures by the absence or impairment of function following lesions. The psychophysical method will involve the use of discriminative conditioning or respiration.