Our team is interested in understanding alterations in the levels of neuromodulators such as dopamine, serotonin or norepinephrine in the brain. Changed levels of neuromodulation are linked not only to many psychiatric disorders, but also influence everyday cognitive performance: Fatigue, excitement and sadness e.g. are all correlated to activity patterns of neurons releasing such neuromodulators. While specific behaviors have been linked to specific neuromodulators, and while activation of certain receptors and their downstream signalling pathways have been associated with these neuromodulators, it still remains largely unknown how neuromodulatory neurons themselves function, how they adapt and how their global projections still allow for area-specificity.
These are complex questions involving numerous different brain structures. We are currently tackling them on various complexity levels: From molecules to neuronal circuits in cell culture all the way up to behaving mice. By combining designer photoreceptors with viral delivery strategies, we can control neuronal activity with light. Our working hypothesis is that these neuromodulatory systems form an overarching structure within local neuronal circuits and concert activity in various brain regions. How these neuromodulatory networks integrate information and how they adapt to environmental stressors or age are key questions of our research.