EFFECTS OF MONOCULAR VISION AND MIDBRAIN TRANSECTION ON MOVEMENT DETECTION IN TURTLE

Employed the optokinetic response to assess the effects of monocular vision and transection of the tectal commissure on movement detection in 37 turtles. Monocular turtles exhibited normal optokinetic nystagmus when the direction of movement was temporal to nasal past the open eye. Movement which was nasal to temporal elicited little or no optokinetic nystagmus. Tectal transection had little effect on optokinetic nystagmus or the habituation of optokinetic nystagmus; however, it did abolish the supernormal response rates which occurred following sudden reversal of stimulus movement. The results support a proposed tectal integrative mechanism involved in movement detection by the turtle. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.