From Synchrotrons to Microwires – a broad view on sensory processing
Group of Neurophysiology of Behaviour at the Francis Crick Institute (London)
In this talk I will present our approach to dissecting information processing in the mammalian brain using the mouse olfactory system as a model.
Odours are transported in turbulent plumes resulting locally in highly fluctuating odour concentration. Yet, whether mammals can make use of the ensuing temporal structure to extract information about the olfactory environment remains unknown. Here, I will show that using a variety of engineering approaches including an automated operant conditioning system we demonstrate that mice can reliably discriminate the correlation structure of odours at frequencies of up to 40 Hz. Consistent with this finding, output neurons in the olfactory bulb show segregated responses depending on the correlation of odour stimuli with populations of 10s of neurons sufficient to reach behavioural performance. This work thus demonstrates that mammals can perceive temporal structure in odour stimuli at surprisingly fast timescales. This in turn might be useful for key behavioural challenges such as odour source separation, figure-ground separation or odour localisation.
I will then briefly introduce technology that we have developed that combines bundles of microwires with CMOS recording chips to allow for scalable, minimally invasive recordings from large numbers of neurons deep in the brain in vivo from sheets of neurons such as the output layer of the olfactory bulb. Finally, to dissect the mechanistic basis of information processing in the olfactory bulb I will present our approaches combining volume electron microscopy and synchrotron CT imaging with functional 2p imaging in vivo to link function to structure over mm length scales
Host: Mazahir Hasan