Researcher in Spotlight – Nathalie Rochefort

Nathalie Rochefort is a Chancellor’s fellow and a Sir Henry Dale fellow at the University of Edinburgh. She is a sensory neuroscientist whose goal is to understand how neural activity in the visual cortex underlies our perception of a visual scene. As an undergraduate, she studied Biology and Epistemology in Paris. She then obtained a European PhD in Neuroscience from the University Paris-VI and the Ruhr-Universität-Bochum and did her post-doctoral training at the Technical University in Munich. Her work during her PhD and post-doctoral training has contributed to a new understanding of how neurons acquire their functional properties in the visual cortex and to the development of a powerful technique, in vivo two-photon calcium imaging, to investigate neuronal functions in the living brain.

The aim of her research group is to reveal how neuronal networks integrate visual information to guide perceptions and actions.

Can you tell us a bit about your research?

We use the mouse primary visual cortex as a model system of cortical integration of sensory and non-sensory information. Neurons in the primary visual cortex respond to specific features of visual stimuli such as their location, their orientation and their direction of movement.

These visual responses do not only depend on the characteristics of the stimuli but are also strongly modulated by the context in which they are perceived, such as the animal’s behavioural state and its previous experience associated with these stimuli. Locomotion, for example, increases the gain of visual responses in the primary visual cortex. Past experience can also durably modify visual cortical responses, for example through the association of a given stimulus with a positive or negative outcome.

By using two-photon calcium imaging combined with electrophysiological recordings in awake behaving mice, our current projects investigate:

  • How visually-guided behaviour modulates neuronal activity in the visual cortex
  • How individual pyramidal neurons integrate feed-forward visual inputs with contextual inputs
  • How cortical information processing is impacted by metabolic state

Using such information, we apply the same combination of methods to study how this network activity is disrupted in the brain of mouse models for autistic spectrum disorders and intellectual disabilities. It is known that atypical selection of sensory features is associated with autistic spectrum disorders. We are probing differences in sensory processing in rodent models of autistic spectrum disorders, with the ultimate goal of identifying drug targets that could be of therapeutic value.

Excitation and inhibition in the visual cortex. Confocal image of a cross-section of the mouse primary visual cortex where all neurons are labeled in blue and subpopulations of excitatory and inhibitory neurons (VIP+) are shown in red and green, respectively.