I work on the properties of neurons and the circuits they form to understand how they control behaviour. 1. Motor control. How do nonspiking local interneurons organise motor neurons to generate limb movements? How do spiking interneurons process the resulting proprioceptive signals during movement and signalling by other sensory neurons. 2. Phenotypic plasticity. Locusts exist in two distinct forms; a solitary phase in which they live independently and a gregarious swarming phase. How does the nervous system control the transition from one phase to another?. What changes occur in the properties of individual neurons and of neurochemicals in the brain? 3. Fast movements. Jumping is one of the fastest and most powerful movements. The actions of circuits of identified neurons, the kinematics of the movements and the mechanics of joints and muscles reveal the mechanisms required to generate these movements.