APB selectively reduces visual responses in goldfish to high spatiotemporal frequencies.

Visual responses of goldfish to rotating square-wave gratings were recorded before and after intraocular injection of 2-amino-4-phosphonobutyric acid (APB). High doses of APB reduced the rate of optokinetic nystagmus (OKN) to a relatively high spatial frequency grating moving at a high temporal frequency. Responses to a low spatial frequency grating were not altered, nor were responses to the higher spatial frequency when it rotated slowly. The effects of APB were transient and lasted no longer than 3 d. We conclude that APB reduces OKN to high spatiotemporal frequencies in goldfish.