The brain is steadily engaged in thought. These internal communications are also usually bombarded with external sensory events. Hence, the impact of the two neuronal processes need to be permanently fine-tuned to avoid their imbalance. A team of scientists at the Ruhr-Universität Bochum (RUB) has now revealed the role of the neurotransmitter serotonin in this mechanism. They discovered that distinct serotonergic receptor types control the gain of both streams of information in a separable manner. Their findings may facilitate new concepts of diagnosis and therapies for neuronal disorders related to malfunction of the serotonin system. The study is published online in the open access journal eLife on 7 April 2020.

Impacting on different streams of information in the brain

Dr. Dirk Jancke, head of the Optical Imaging Group at the Institute of Neural Computation, says, “Imagine sitting with your family at dinner, and a heated debate is going on about how to properly organize some internal affairs. Suddenly, the phone starts ringing; you are picking up while family discussion goes on. In order to understand the calling party correctly, the crowd in the back must speak lower or the caller needs to speak up. Thus, the loudness of each internal background conversation and external call need to be properly adjusted to ensure non-interfered, separable information transfer.” As in this anecdote, comparable brain processes involve serotonin.