Max-Planck-Institute for Medical Research, Heidelberg, Germany
University of Geneva, Switzerland
Indian Institute of Science Education and Research, Pune
I started my research career fascinated by an interesting question, how the brain processes complex sensory information and create a percept of the sensory world that leads to actions? To start addressing this question I joined Prof. Obaid Siddiqi’s lab at NCBS as a predoctoral student. He convinced me about the power of ‘sense of smell’ as a tool to dissect this question. The olfactory conditioning of fruit flies caused the improvement in reaction times towards conditioned odours. This finding made me to think and focus on the psychophysical aspect of the olfactory processing in higher organisms. During my PhD, I focused on the mechanisms of fine odour discriminations using mouse as the model system. We quantified the temporal course of olfactory decision-making by using simple and complex stimuli. Mice discriminated simple odours in ≈200 ms and complex binary mixtures with additional tens of milliseconds. Such olfactory representation can be maintained in the olfactory bulb (OB) plausibly by the inhibitory network. We tested this hypothesis by altering the function of inhibitory interneurons, granule cells (GCs), in the OB. A bidirectional shift in the synaptic inhibition caused a similar effect in the discrimination speed for complex odorants.
Then I moved to University of Geneva where we investigated how the GC inhibition controls the output of OB. We have also investigated the factors controlling odour discrimination efficiency at the sensory input level. Strikingly, olfactory associative learning caused a long-lasting potentiation at the sensory input level that may help improving odour detection thresholds.
Now, with the support from Wellcome-DBT, we will focus on synaptic and molecular mechanisms of sensory perception and decision-making by giving special attention to different inhibitory circuits of mouse OB. Initially our focus would be on basic mechanisms of synaptic inhibition, followed by understanding behavioural neural networks in model organism. Once we achieve this, the next step would be focusing on the dysfunctions of human brain resulting from the imbalance between excitation and inhibition.