Nicholas J. Strausfeld
Professor of Neurobiology and Cell Biology and Anatomy
Ph.D., University College, London
E-mail: flybrain@neurobio.arizona.edu
Research Interest:
Analysis of complex neural networks in sensory system
Our research group is focusing on the functional organization of neural networks underlying visual behavior, and underlying multimodal sensory integration in complex motor programs. The insect nervous system provides a "model" of comparable networks in vertebrates. Current research strategies include sophisticated anatomical procedures coupled with intracellular recordings from identified neurons, behavior and microsurgery.
Three projects are currently being pursued in our laboratory. The first is analyzing the organization of sex-specific visual interneurons which in male calliphorids underlie a sex-specific region of high retinal acuity. Behavioral studies suggest that this region is used to detect small high contrast objects which are then intercepted and chased. Neuroanatomical and intracellular studies demonstrate that male-specific visual neurons subtend characteristic frontal areas of the visual space and respond to velocity/motion and small-field positional cures. Chasing flies must ignore panoramic motion which would otherwise provide cues to compensate for turning movements. An important component of current work is investigating how male-specific channels interact with wide-field optomotor neurons to mediate saccadic movement and retinal image stabilization.
The second project focuses on the integration of wide-small-field, and mechanosensory data at premotor channels governing systems that separately control thrust (power) and torque (steering) during flight. Again, a variety of techniques are used to analyze these pathways, including immunocytochemistry of possible inhibitory elements.
The third project investigates long term modulation of premotor pathways, focusing on complex centers (corpora pedunculata) in the brains of social insects. These regions, which receive inputs from olfactory and visual neuropils, share certain structural features in common with mammalian hippocampus. Chronic recordings of trained animals, as well as microsurgical interruptions of axons in the corpora pedunculata, suggest that these centers play an important role in coordinating motor programs, and may possibly be involved in spatial memory.
Selected Publications:
Strausfeld NJ, Weltzien P, Barth FG (1993) 2 visual systems in one brain - neuropils serving the principal eyes of the spider cupiennius-salei. J Comp Neurol 328:63-75.
Strausfeld NJ, Barth FG (1993) 2 visual systems in one brain - neuropils serving the secondary eyes of the spider cupiennius-salei. J Comp Neurol 328:43-62.
Gilbert C and Strausfeld NJ (1992) Small-field neurons associated with oculomotor and optomotor control in muscoid flies:functional organization. J Comp Neurol 316:72-86.
Gronenberg W and Strausfeld NJ (1992) Premotor descending neurons responding selectively to local visual stimuli in flies. J Comp Neurol 316:87-103.
Gilbert C and Strausfeld NJ (1991) The functional organization of male-specific neurons in flies. J Comp Physiol 169:395-412.
Gronenberg W and Strausfeld NJ (1991) Descending pathways connecting the male-specific visual system of flies to the neck and flight motor. J Comp Physiol 169:413-426.
Strausfeld NJ and Lee JK (1991) Neuronal basis for parallel visual processing in the fly. Vis Neurosci 7:13-33.
