OVERVIEW

Animals exhibit behavioral repertoires that are often innate and result in stereotyped sexual and social responses to their environment. Innate behaviors do not require learning or experience and are likely to reflect the activation of developmentally programmed neural circuits. We are interested in the nature of defined neural circuits: how activation of circuits elicits specific behaviors.

It has been extremely difficult in complex organisms to study a circuit beyond the early stages of sensory processing. Drosophila melanogaster is an attractive model system to understand a circuit because flies exhibit complex behaviors that are controlled by a nervous system that is numerically five orders of magnitude simpler than that of vertebrates.

We use a combined behavioral, genetic, imaging and electrophysiological approach to determine how defined neural circuits and their activation elicit specific behaviors.

Main Interests

Identification of the neural circuits and mechanisms that control innate, or instinctive, behaviours

Methods

Optogenetics, Imaging, Behaviour and Genetics

Models and Regions

Drosophila melanogaster, Whole brain

STRATEGY

To dig down into the neural circuitry of innate behaviour, the team focuses on two main behaviours – the relatively simple avoidance of a repulsive odour and the more intricate courtship behaviour. Both behaviours are studied in the fruit fly Drosophila melanogaster, a powerful model system that offers a wide range of advanced techniques. These include genetic tools and manipulations to help to identify which neurons are involved in specific behaviours and optogenetic tools to monitor the activity of neurons by using changes in calcium level for instance, a proxy for neural activity.

Together, these tools enable the researchers to pin down the anatomical and functional components of neural circuits. The team uses these tools together with highly detailed video monitoring to establish the most precise relationship between behaviour and neural activity. The team studies different brain areas to understand each of these behaviours. Specifically, to study odour avoidance, the team investigates how two higher-order olfactory centres of the fly’s brain interact to generate escape behaviour. Studying the more complex courtship behaviour, however, may lead to any part of the brain, turning it into a very exciting journey, which began with the lab’s recent discovery of a set of neurons that is required for the female to respond adequately to male courtship.