Neuronal basis for parallel visual processing in the fly

作者：Nicholas James Strausfeld, Jong-Kyoo Lee · 发表于：Visual Neuroscience · 年份：1991 · DOI：10.1017/s0952523800010919 · 被引用次数：162 · 研究领域：Neurobiology and Insect Physiology Research、Visual perception and processing mechanisms、Plant and animal studies

Behavioral and electrophysiological studies of insects demonstrate both spectrally independent and chromatically dependent behaviors and interneurons. This account describes the neuroanatomical identification of two parallel retinotropic subsystems, one supplying descending channels to spectrally independent neck and flight motor circuits, the other supplying polychromatic channels to neuropils associated with leg motor circuits in the thoracic ganglia. In the compound eye, two classes of photoreceptors contribute to each of several thousand sampling units. High-sensitivity, chromatically uniform short-axon photoreceptors (R1-R6) supply the lamina's external plexiform layer and are presynaptic to L1, L2 efferents. These project in parallel with a second system of trichromatic long-axon receptors and the L3 efferent. Both pathways supply columns of the medulla, equal in number to ommatidia. Golgi and cobalt-silver impregnation demonstrates that neurons from the medulla diverge to two deeper regions, the lobula plate and lobula, the former a thin tectum of neuropil dorsal to the more substantial lobula. Layer relationships between medulla neurons and their afferent supply suggest that the lobula plate and lobula are each supplied by one or the other, but not both, of the two parallel subsystems. Independence of the two parallel pathways is suggested by ablation of the photoreceptor layer leading to selective degeneration of the motion-sensitive lobula plate neuropil. In additio...