Feeling tense or anxious in social situations is natural. While some anxiety symptoms are mild and manageable, others can be bothersome and distressing to others. Various anxiety treatment medications are already available; however, most of them are ineffective and have undesirable side effects, according to a report by Boldsky citing the scientific journal eLife.
**Mechanisms of Fear and Anxiety in the Brain**
In a recent study, researchers at the University of Bristol identified a new target in the brain that supports the triggering of anxiety and fear behaviors. The researchers state that their discovery of brain pathways could lead to a new pharmacological target for treating anxiety and mental disorders, which affect over 264 million people worldwide.
**Cerebellum and the PAG Region**
The Faculty of Physiology, Pharmacology, and Neuroscience at the University of Bristol studied how the cerebellum, linked to several brain regions associated with survival networks, influences activity in the gray area around the PAG (periaqueductal gray) region. The PAG is situated at the center of a network coordinating survival mechanisms, including responses that trigger fear symptoms and limb immobility.
Dr. Charlotte Laurenson and Dr. Elena Pasi, the study's principal researchers, stated, “So far, little has been understood about how the cerebellum modulates neural activity in other brain areas, especially those related to fear and anxiety. Importantly, the study's findings illustrate that the cerebellum is part of the brain's survival network, regulating fear memory processes across multiple time scales and in various ways, increasing the likelihood that dysfunctional interactions in the cerebellum's survival network may underlie fear-related disorders and accompanying illnesses.”
**Better Treatments**
Anxiolytic medications do not yield effective results for all patients and often have undesirable side effects. Therefore, studying the brain networks and mechanisms underlying fear and anxiety may lead to the development of better treatments for stress and anxiety disorders.
The researchers recorded activity in the PAG region of animal models' brains using electrodes. The models received an auditory tone paired with a small foot shock as part of a conditioning task, which in turn triggered a "fear memory." During the encoding of the fear memory, researchers found that a subset of brain cells in the PAG showed heightened responsiveness to the conditioned tones.
**Encoding Fear Memory**
The study provides new insights into how the PAG encodes fear memories and also indicates that the cerebellum is another key brain structure in the fear and stress network, offering new hope for treating psychological conditions such as post-traumatic stress disorder.
