Focal attention in the frog: behavioral and physiological correlates.

The prey-catching response of frogs toward small moving objects can be facilitated by small movements of the same stimulus a few seconds earlier, even though initial movements seldom trigger the feeding response. This focal attention phenomenon may be related to the observation that one class of tectal unit continues to discharge for a few seconds following a brief stimulus motion. Together with anatomical data of other investigators, results of the present study suggest that self-exciting neural loops within the tectum mediate this type of selective attention.