THE LEVEL – Your heart rate jumps. Your blood pressure soars. Your pupils dilate. This is what researchers say happens when you feel fear and anxiety.
Although the signs of fear and anxiety are easily recognized, the origin of its stimulators have remained relatively unknown – until now.
Scientists at the UNC School of Medicine recently announced they have pinpointed the population of brain cells whose activity drives fear and anxiety responses in mice. That is good news to mental health advocates, who hope the discovery may lead to new advances or, eventually, the prevention of anxiety disorders, depression and other mental health issues in humans.
The scientists, whose study is published in Cell Reports, found that artificially forcing the activity of these brain cells in mice produced an arousal response in the form of dilated pupils and faster heart rate. It also worsened anxiety-like behaviors.
These findings help to illuminate the neural roots of emotions, according to scientists, who hope to replicate the same findings in humans.
Although tens of millions of U.S. adults receive treatment to alleviate the symptoms of anxiety, depression, and other disorders, many have adverse effects.
Scientists believe the combination of activating these BNST (bed nucleus of the stria terminalis) Pnoc neurons and future drugs may provide safer and more effective treatments.
First author Jose Rodríguez-Romaguera, PhD, assistant professor in the UNC Department of Psychiatry and member of the UNC Neuroscience Center, and co-director of the Carolina Stress Initiative at the UNC School of Medicine, and co-first author Randall Ung, PhD, an MD-PhD student and adjunct assistant professor in the Department of Psychiatry, led the study as members of the UNC laboratory of Garret Stuber, PhD, who is now at the University of Washington.
Other co-authors of the study include: Hiroshi Nomura, James Otis, Marcus Basiri, Vijay Namboodiri, Xueqi Zhu, Elliott Robinson, Hanna van den Munkhof, Jenna McHenry, Louisa Eckman, Oksana Kosyk, Thomas Jhou, Thomas Kash and Michael Bruchas.
The research was supported by the National Institute of Mental Health, the National Institute of Neurological Disorders and Stroke, the National Institute on Drug Abuse, the Children’s Tumor Foundation, the Brain and Behavior Research Foundation and the Yang Biomedical Scholars Award.
Editor’s Note: Read the full study in this edition of Science Daily.