Andreas Keller

Throughout life, we learn, experience, and discover. Our brain integrates this wealth of ever-changing information in a model of the world. This challenging task requires long-term changes in neuronal circuits that should not interfere with already stored memories or with ongoing processing. To minimize interference, it has long been speculated that the coordination of the integration of new memories involves global brain-state changes as they occur e.g. during sleep.
Whether this gating of plasticity is implemented through global brain-state changes and, if so, what the underlying mechanisms are remains largely unclear. One brain structure which continuously processes sensory information, but is fundamentally reshaped by experience, even in adult animals, is sensory cortex. It is increasingly clear that activity in sensory cortex is driven both by feedforward input as well as context-dependent feedback signals. Both these pathways are shaped by experience without overtly interfering with cortex-dependent visual-guided behaviors, preserving a stable representation of the world.

The aim of our research is to uncover the mechanisms that gate plasticity to shape cortical circuits during learning, while maintaining normal brain function. This will involve research on neuronal circuits, the development of novel technologies for the chronic manipulation and recording of neuronal activity, and of strategies for targeted interventions that enhance plasticity.

The focus of our lab can be summarized as follows:

- What changes in cortex when we form a memory?
- What are the mechanisms?
- How can we take advantage of these mechanisms to promote plasticity during learning?

To address these questions we use combinations of techniques that include behavioral tasks, two-photon imaging, wide-field imaging, neural circuit tracing, electrophysiology, EEG, EMG, targeted opto- and chemogenetics.