In a new study, scientists may have discovered a neurobiological marker that could help identify patients with post-traumatic stress disorder (PTSD). They found that individuals with PTSD show an enhanced brain response to slight changes in tone.

Using an electroencephalogram (EEG) — a test that detects electrical activity in a person’s brain via electrodes attached to their scalp — researchers at the Universities of Birmingham and Amsterdam studied the brain activity of a group of thirteen patients with PTSD. They then compared these results to those of individuals who had experienced a similar trauma but had not gone on to develop PTSD.

“We know that a symptom of PTSD can be heightened sensory sensitivity,” said Dr. Ali Mazaheri of the University of Birmingham’s School of Psychology and Centre for Human Brain Health.

“In this study, we tested the brain’s response to a simple auditory sensory change by playing simple (standard 1000 Hz) tones every second, and then intermittently playing a slightly altered tone (1200 Hz), known as a deviant,” he said.

“What we found was that patients who had developed PTSD showed enhanced brain responses to deviant tones, suggesting their brain over-processed any change in the environment. Importantly we found the more enhanced their response was, the more poorly they performed on cognitive tests looking at memory.”

PTSD can be triggered from numerous traumatic events including serious road accidents, violent personal assaults, witnessing violent deaths, military combat, being held hostage, terrorist attacks, and natural disasters. Symptoms may include severe anxiety, guilt, isolation insomnia, nightmares, depression, agitation, flashbacks, and declines in memory and concentration.

“These symptoms are often severe and persistent enough to have a significant impact on the person’s day-to-day life. Therefore it is vital that we find new ways to treat the condition and also assess treatment outcomes,” said Professor Miranda Olff of the University of Amsterdam and Arq Psychotrauma Expert Group.

Approximately one in every ten people who suffer a traumatic experience will go on to develop PTSD. The disorder can develop immediately after the traumatic event or it can begin weeks, months or even years after the event.

“This is the first research study of its kind. The neurobiological evidence we now have shows how altered brain activity of a patient with PTSD is closely related to the way it processes the world,” said Katrin Bangel of the University of Amsterdam.

“What’s more, this study is very unique in that it compared PTSD patients with a control group of those that also suffered similar trauma but didn’t develop PTSD, rather than a control group who had no trauma or PTSD — this really allows us to look at what triggers PTSD following significant trauma.”

The research team is conducting more studies to confirm the marker and is planning a clinical trial to test potential treatments on patients with PTSD. If confirmed, the marker could be used to help diagnose PTSD as well as assess if a patient is getting better with treatment.

Source: University of Birmingham

PTSD Patients Show Heightened Sensitivity to Deviant Sounds