Neuronal ensembles encoding distinct modalities in the mouse somatosensory cortex

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How does the brain allow you to tell the difference between warmth and cold?

Cortical circuits which represent and encode distinct somatosensory modalities, such as heat, cold and pressure, and delineate them from each other are not well understood. Modality-specificity could come about via distinct hard-wired cortical circuits or via distinct spatiotemporal patterns of activity generated within common set of cortical neurons.

By performing multiphoton imaging of neuronal activity in the somatosensory cortex in vivo, we aim to identify cortical ensembles encoding distinct sensory modalities using genetically-encoded calcium indicators and to study underlying principles. We will also address how intensity-coding is generated. Importantly, we plan to study the nature of sensory-encoding ensembles across the distinct cortical layers, and we will study its relation to intracolumnar connectivity.
We further aim to address the role of cortical inhibition in generating and modulating these ensembles via background suppression. Do all interneurons sculpt the respective spatiotemporal activity patterns in the same way, or are distinct modalities related to distinct classes of interneurons which form the respective sensory codes?
These integrative approaches are expected to provide insights into neuronal ensembles mediating specific modalities of perceptions, which in turn guide specific behaviors. In a broader perspective, we use our model system to ask how functional specificity is generated in cortical circuits.
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*Principal investigators of other projects within the CRC