Military recruits who were trained to change their own brain activity through neurofeedback protocol showed reduced alexithymia, a condition marked by a lack of emotional awareness in a clinical trial involving 180 participants published this week in Nature Human Behaviour.

Neurofeedback training, which provides participants with information about brain activity levels and trains them to regulate these activity levels, is regarded as a promising area of development for improving stress resilience and for psychiatric treatment, including for post-traumatic stress disorder. However, most neurofeedback routines rely on expensive, specialized imaging equipment that can detect deep brain activity, such as functional magnetic resonance imaging (fMRI)

Jackob Keynan, Talma Hendler and colleagues report a clinical trial implementing a recent electro-encephalogram (EEG) based neurofeedback routine designed to target brain activity in the amygdala, which is a region known to be involved in emotional processing. The equipment used to monitor EEG in neurofeedback is more scalable, portable and costs less than fMRI.

The authors randomly assigned 180 recruits undergoing stressful military combat training to one of three groups. The experimental group received six EEG-based neurofeedback sessions targeting amygdala activity, while another 45 recruits received EEG-based neurofeedback training that did not target the amygdala and served as a closely matched control. The final 45 recruits received no neurofeedback. The authors found that only the amygdala-targeting neurofeedback training sessions led to reduced alexithymia.

The authors suggest that their findings may pave the way for real-world applications to protect individuals from developing stress-related disturbances.