Fear is one of the most natural and primitive of all human emotions. It helped our ancestors avoid certain deaths throughout our evolutionary history, and today it continues to keep modern man safe, as he constantly adapts to the world’s ever-changing dangers. It’s when fear interferes with our lives that it becomes a topic of concern. A recent study has delved deeper into our understanding of fear, and its findings may help to develop ways to deal with unhealthy fear, such as post-traumatic stress disorder.

When fear becomes uncontrollable, it can leave a person unable to properly function in society. Post-traumatic stress disorder is a mental health condition triggered by a terrifying event. It’s estimated to affect around eight percent of the population at some point in their lives, and in many cases can leave an individual unable to carry on with his daily routine.

There are a number of psychotherapy treatments as a well as drugs offered to individuals suffering from this disorder, but often even these approaches fail to yield positive results. A recent study from the University of Texas, Dallas, has helped scientists to further understand the inner workings of fear comprehension in the brain, and researchers are hoping this knowledge can serve as the foundation for future work involving alternative treatments for PTSD patients.

When embarking on this journey into the human mind, the researchers had one clear goal: to understand how fear arises in the brain when individuals are exposed to threatening images. “We are trying to find where thought exists in the mind,” explained Dr. John Hart Jr., one of the researchers involved in the study, in a press release. The researchers used a device called an electroencephalography (EEG) to observe human brains when exposed to both threatening and non-threatening stimuli.

Results showed that there was no difference in reaction time for threatening versus non-threatening images, but this did not mean the brain responded to both in quite the same way. Thanks to the EEG technology, the researchers were able to observe that threatening images evoked an early increase in theta activity in the occipital lobe, where visual information is processed, followed by a later increase in the theta power in the frontal lobe, where higher mental functions such as thinking and planning occur. The area of the brain associated with motor behavior, such as the impulse to run, also seemed to be stimulated by the threatening images.

Although now these findings are little more than words on a paper, their future applications are immense. "We have known for a long time that the brain prioritizes threatening information over other cognitive processes," explained study lead author Bambi DeLaRosa. "These findings show us how this happens.” Knowing how this happens may prove essential in treating abnormal fear associated with an object for a wide variety of individuals, including those living with PTSD.

Source: DeLaRose BL, Hart J, Spence JS, et al. Electrophysiological spatiotemporal dynamics during implicit visual threat processing. Brain and Cognition. 2014.