Marcel Oberlaender

In Silico Brain Sciences
We reconstruct neural networks and elucidate mechanistic principles of how the brain integrates sensory information.

Research focus

The overarching goal of our research is to understand how the interplay between biophysical, synaptic, cellular and network mechanisms in the mammalian brain can encode perception and trigger behavioral responses, such as decision making during a sensory-motor task. To pursue this goal our group employs a multidisciplinary approach, combining network anatomy (reconstruction of synaptically connected local and long-range circuits in the brain using different virus-based and/or in vivo labeling approaches) with cellular physiology (measurement of neuronal activity patterns in the neocortex and thalamus via patch-clamp recordings and/or optogenetic approaches in vivo), and computational modelling (simulations of sensory-evoked signal flow through well-constrained neuronal network models).

Understanding how the brain is able to transform sensory input into behavior is one of the major challenges in systems neuroscience. While recording/imaging during sensory-motor tasks identified neural substrates of sensation and action in various areas of the brain, the crucial questions of 1) how these correlates are implemented within the underlying neural networks and 2) how their output triggers behavior, may only be answered when the individual functional measurements are integrated into a coherent model of all task-related neuronal circuits. Our group uses the whisker system of the rat for building such a model in the context of how a tactile-mediated percept (e.g. object shape via whisker touch) is encoded by the interplay between biophysical, cellular and network mechanisms. Rodents, such as rats and mice, actively move their facial whiskers to explore the environment. Our group has developed approaches for generating a digital (i.e., in silico) representation of the rodent whisker system. We generate anatomically and functionally detailed neuronal network models that allow performing computer simulations that mimic the in vivo stream of whisker-evoked excitation throughout the brain, at subcellular resolution and millisecond precision. These simulations provide unique opportunities to investigate how the interplay between different cellular and network properties can give rise to neural substrates that underlie sensory information processing, and ultimately sensory-guided behaviors.