A quantitative correlation of contour sensitivity with dendritic density in an identified visual neuron.
Crayfish sustaining fibers are visual interneurons that are tonically excited by increases in illumination within their receptive fields. The receptive fields of sustaining fibers (SFs) are correlated with the two-dimensional position of their dendritic fields within the central neuropil. Dendritic branching patterns and contour sensitivity maps were obtained for SF 019 in several preparations. The contour sensitivity along the dorsal-ventral visual arc (which intersects 019's receptive field) is positively correlated with the variations in the spatial frequency of 019's dendritic arbor along the dorsal ventral midline of the neuropil. We conclude that an SF's receptive field is determined by the position and extent of its dendritic field and that sensitivity variations within the receptive field are principally determined by changes in its dendritic density.
D000818:Animals; D003400:Astacoidea / Q000502:physiology*; D003712:Dendrites; D005260:Female; D005556:Form Perception / Q000502:physiology*; D007395:Interneurons / Q000648:ultrastructure; D008297:Male; D014795:Visual Pathways / Q000166:cytology*