Neurogenetics and the 'fly-stampede' Dissecting neural circuits involved in visual behaviors

摘要

A central goal of systems neuroscience is to understand how neural circuits represent quantitative aspects of the outside world and transform these signals into the motor code for behavior. By contrast to olfactory perception in which odors are encoded by a population of ligand-binding receptors at the input stage, the visual system extracts complex information about color, form and movement from just a few types of photoreceptor inputs. The algorithms for many of these transformations are poorly understood. We designed a high throughput real-time quantitative testing system, the "fly-stampede", to evaluate behavioral responses to light and motion cues in Drosophila. With this system, we identified a neural circuit that does not participate in sensing light but is crucial for computing visual motion. When neurons of this circuit are genetically inactivated, the flies show normal walking phototaxis, but are completely motion blind. Using neurogenetics to study the circuits mediating sophisticated animal behaviors is currently a field of intense study. This extra view attempts to summarize our work within historical background of fly biocybernetics and other recent advances.