Brain Auditory Response Altered In Post-traumatic Stress Disorder

A novel neurobiological marker to help recognise patients with post-traumatic stress disorder has been found by scientists at the Universities of Birmingham and Amsterdam.

Using an electroencephalography, researchers studied the brain activity of a group of thirteen patients with post-traumatic stress disorder (PTSD). The group was then compared to a group who had suffered a similar trauma but had not gone on to develop PDST.

PTSD is estimated to affect about one in every ten people who have a traumatic experience. It can develop immediately after someone experiences a disturbing event or it can occur weeks, months or even years later and can affect a person’s memory.

Heightened Sensory Sensitivity

Dr Ali Mazaheri, of the University of Birmingham’s School of Psychology and Centre for Human Brain Health, said:

“We know that a symptom of PTSD can be heightened sensory sensitivity. In this study, we tested the brain’s response to a simple auditory sensory change by playing simple (standard 1000Hz) tones every second, and then intermittently playing a slightly altered tone (1200 Hz), known as a deviant. 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.”

The type of events that can cause PTSD include serious road accidents, violent personal assaults, witnessing violent deaths, military combat, being held hostage, terrorist attacks and natural disasters.

Neurobiological PTSD Marker

Katrin Bangel, of the University of Amsterdam, said:

“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. 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.

We now potentially have a new neurobiological marker for PTSD patients that maps to their own individual symptoms. This marker, if validated, could be used to assess if an individual is getting better with treatment. It can also be potentially used in diagnosing patients.”

The team has now begun further research validating the marker and also plans a clinical trial to test potential treatments on patients with PTSD.

Katrin A. Bangel, Susanne van Buschbach, Dirk J. A. Smit, Ali Mazaheri & Miranda Olff
Aberrant brain response after auditory deviance in PTSD compared to trauma controls: An EEG study
Scientific Reports 7, Article number: 16596 (2017)

Top Image: Katrin A. Bangel et al. CC-BY