The role of interneurons in plasticity of sensory representations during reward learning

• Applicant: Dr. Katharina Anna Wilmes
• Subject Area: Cognitive, Systems and Behavioural Neurobiology
• Term: from 2017 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 398005926

Our brains enable us to quickly learn which behaviours lead to a reward. How do rewards influence learning processes in the brain? Learning happens on the level of synapses between neurons during behaviour. New optogenetic techniques to monitor and control particular neuron types in behaving mice revealed neuronal circuits in sensory areas that are modulated by rewards. These circuits consist of principal neurons and diverse interneuron types. So far, research on learning has primarily focused on principal neurons and the changes in their synaptic connections (synaptic plasticity). Synaptic plasticity is thought to be the correlate of learning. However, interneurons were recently shown to play a role for learning. Indeed, their synapses are highly plastic, and moreover, they receive input from the forebrain, which processes rewards. Our knowledge about interneuron circuits is still very limited; experimental measurements can take only snap shots of the system. Therefore, it is yet unknown how neuronal circuits (including interneurons) change during learning, and how reward signals (top-down signals) guide these changes. The proposed project addresses this knowledge gap by adopting a theoretical approach, as computational modelling of neuronal circuits allows us to study complex interactions between neurons. In this project, I will utilise both abstract network models and more biologically detailed network models to understand how top-down signals modulate (1) changes in connectivity between principal neurons, (2) changes in connectivity in the interneuron network, and (3) how the interneuron network influences principal neuron connectivity. The aim of this project is to uncover cellular and circuit mechanisms by which top-down modulation guides learning in the brain, and thereby advance our understanding of learning and learning-related diseases.

• DFG Programme: Research Fellowships
• International Connection: United Kingdom
• Host: Professorin Dr. Claudia Clopath