Science Topics – 134
The brain has the “emotion” circuits that process signals of psychological stress and other emotions. The stress and emotion signals elicit a variety of body’s responses by affecting the circuits controlling the “body” conditions. For example, psychological stress increases body temperature, heart rate and blood pressure in many mammals including humans. However, the brain circuit mechanism by which stress and emotion signals act on the vital circuit systems, such as the autonomic nervous system, has long been unknown.
We discovered a central psychosomatic neural pathway that transmits stress signals from the dorsal peduncular cortex and dorsal tenia tecta (DP/DTT), an unexplored medial prefrontal cortical area, to the dorsomedial hypothalamus (DMH), a hypothalamic center controlling the sympathetic nervous system. Optogenetic stimulation of the DP/DTT→DMH pathway elicited increases in metabolic heat production, heart rate and blood pressure, mimicking sympathetic responses to psychological stress. On the other hand, genetic lesion or optogenetic inhibition of this pathway eliminated psychological stress-induced increases in heat production, body temperature, heart rate and blood pressure, and also suppressed avoidance behavior from stressors.
These findings demonstrate that the discovered DP/DTT→DMH pathway drives a variety of autonomic and behavioral stress responses by connecting the corticolimbic emotion circuits to the hypothalamic motor control circuits. This discovery of the “mind–body” connection potentially contributes to future development of novel strategies for treating stress-related disorders.
Kataoka N, Shima Y, Nakajima K, and Nakamura K. A central master driver of psychosocial stress responses in the rat. Science 367(6482): 1105-1112, 2020.
https://doi.org/10.1126/science.aaz4639
＜Figure Legends＞
Psychosomatic neural circuit. Signals of psychological stress and emotions are processed in the corticolimbic “emotion” circuits and integrated in the DP/DTT. The integrated signals are transmitted to the DMH to drive a variety of sympathetic and behavioral responses through the circuits controlling the “body”. The discovered "mind–body" connection constitutes a key part of the psychosomatic brain circuit.
Department of Integrative Physiology, Nagoya University Graduate School of Medicine, Japan