QBI visual and sensory neuroscientists have demonstrated that many relatively simple nervous systems nevertheless display a rich behavioural repertoire, and are useful model systems to study mental disorders linked to sensory brain function. Also, an understanding of sensory processing in insects may provide simple, novel solutions to problems in machine vision, flight control, and robot navigation. QBI scientists seek to elucidate principles of vision, olfaction, and memory, and to explore the limits of the 'cognitive' capacities of small brains.