Book Description
The report covers results of studies of neural information processing in the compound-eye visual systems of insects subject to a restricted class of visual object stimuli. In the first phase of the research, the behavior of single visual units in the optic lobes of Romalea were described and categorized. Eight types of operation on visual objects were defined. Similar operations were observed in single visual units in the optic lobes of Locusta and Schistocerca. In the second phase of the study, spatial resolution was examined for a variety of classes of visual unit in the locust. The anomalous 0.3 degree resolution of the VNC giant fiber was verified for spot checkerboard stimuli, as well as a radial grating. The 'edge effect' for the radial grating was seen to give enhanced response with the mask when max. stripe period was above a certain limit, and to be spoiled by the mask when below the limit. The resolution of vector units in the 3rd cervical nerve was tested, and found to follow Nyquist theory. Results suggested that a 2-mode-system may exist in insect vision: one to measure, without regard to form, local changes in light intensity over the eye; the other responding to object form-in-motion. The latter system is subject to the constraints of spatial sampling theory. (Author).