Spread of excitation along neuron chains of the frog tectum opticum in response to various visual stimuli.

The construction of "chains of excitation" based on latent periods of responses of silent neurons of the frog tectum opticum to repetitive visual stimuli revealed significant differences in the course of excitation of the neuronal structures during the action of simple (flashes) and complex (movement of a visual object) stimuli. Movement of excitation over tectal neurons is shown to be very complex in character, for whereas the excitation wave develops comparatively quickly in response to simple stimuli and narrowing of the pathway of excitation soon arises, in response to a stimulus of definite shape it lasts longer and the pathway of excitation remains comparatively constant in width for much longer.