Abstract
Visualizing a target in visual clutter is a complicated task that has been successfully solved in flying insects, despite being equipped with low-resolution eyes and small brains. Their high-speed, highly acrobatic aerial interactions with conspecifics and prey are evidence of this. While many insects pursue small targets, some show even more exquisite control, e.g. males of the highly territorial hoverflies, and both sexes of the efficient predatory dragonflies. We recently described neurons in the insect lobula complex (third optic ganglion), which are sharply tuned to the motion of small targets and respond robustly to these even when displayed against complex moving backgrounds. These small target motion detector (STMD) neurons are thus likely to underlie pursuit behaviors. While we have been able to start to investigate the neurophysiology of STMDs, the mechanisms that underlie the amazing ability to extract targets from a cluttered background are still poorly understood. Higher-order visual neurons tuned to motion cues are relatively easy to record from in insects (as compared with the vertebrate visual cortex) making this an excellent model system for understanding the mechanisms underlying sensory selectivity. In this talk I will particularly emphasize the mechanisms by which insect STMDs extract salient features from a noisy surround, and how this could provide unifying principles underlying the generation of sensory selectivity.