Understanding key components of the brain’s stress circuitry

2018

Challenge

The paraventricular nucleus of the thalamus (PVT) is a brain structure that has been identified as a player in emotional processing, learning, and responses to stress. Although knowledge of this brain structure’s role in stress responses is growing, researchers are still working to understand how the PVT is organized and how it is connected to other parts of the brain.

Advance

NIH researchers led by Mario A. Penzo, Ph.D., investigated the cellular and circuit mechanisms by which stressors affect PVT function. To do this, the researchers examined the contributions of different neurotransmitter systems in the PVT and found that, during stress, the chemical dopamine — a major modulator of brain function — reduced the inhibitory signals sent from certain neurons to the PVT. Moreover, this lower level of inhibition made the PVT more sensitive to aversive outcomes.

Impact

The findings help clarify the structural and functional roles of an important part of the brain’s stress circuity and provide a platform for future research into how the brain responds to, and is affected by, stress.

Publications

Beas S, Wright J, Skirzewski M, Leng Y, Hyun H, Koita O, Ringelberg N, Kwon B, Buonanno A, Penzo M. (2018). The locus coeruleus drives disinhibition in the midline thalamus via a dopaminergic mechanism. Nat Neurosci. 21:963-973.