Precise endogenous control of involvement of right and left visual structures in assessment by zebrafish.

Birds and fish use monocular viewing to bring to bear appropriate lateralised specialisations. In larval zebrafish, persistent left eye (LE) viewing of their own reflection is interrupted by a series of brief 'events', in which the right eye has equal use. These recur with precise 160 s periodicity, with the first beginning after 40s, and allow right and left mechanisms to assess the reflection.