The brain produces a variety of electrical and chemical changes in response to fear and other emotions. Fear is a complex emotion that is characterized by a feeling of anxiety or threat and is accompanied by physical and behavioral responses such as increased heart rate, rapid breathing, and the release of stress hormones.
Studies using brain imaging techniques such as functional magnetic resonance imaging (fMRI) have found that fear activates a number of specific brain regions, including the amygdala, the insular cortex, and the prefrontal cortex. These areas are involved in the processing of emotions, including fear, and are thought to play a key role in the experience of fear.
It is not clear what specific frequencies the brain produces during fear, as this has not been studied in detail. However, it is known that the brain produces a variety of electrical and chemical changes in response to fear and other emotions that are associated with changes in brain activity and function.