Pursuing a multi-level understanding of memory and motivation.

The ability to appropriately direct behaviour using our memories is something we take for granted. However, in certain disease-states, such as affective disorders and addiction, our motivational control goes awry and behaviour runs amok. My goal is to understand detailed neural mechanisms of memory and motivation. We will use state-of-the-art genetics, physiology and behaviour to interrogate the relatively simple nervous system of the fruit fly Drosophila at the molecular, cellular and neural ne twork level. We will identify and characterize neural circuits that are modified by experience, and that are required for memory formation, consolidation and retrieval. We will profile gene expression in the relevant neurons before and after training using microarrays and will use neuron-specific transgenic RNA-interference with behavioural assays to find conserved memory-relevant genes. Appetitive memory is only efficiently retrieved in hungry flies and we have discovered the neurons that are c ritical for this motivational control. We will use a combination of genetics, behaviour and physiology to understand the detailed mechanisms that the motivational states of hunger and satiety utilize to conditionally alter neural circuit properties and expression of adaptive behaviour.