Around 70% of women who suffer a sexual assault develop PTSD; now scientists have shown that many of these women show a marked reduction in the usual communication between two important brain areas involved in processing and control of emotions, the amygdala and the pre-frontal cortex. In some women, synchronisation between these areas can drop to near zero. This work is presented at the ECNP conference in Amsterdam.
Worldwide, between 17% and 25% of women undergo a sexual assault, with around 70% subsequently developing PTSD (Post-Traumatic Stress Disorder). Previous PTSD studies, after natural disasters, accidents or war, have revealed changes in how the brain communicates. Now a group of Spanish scientists have shown that sexual assault can lead to similar brain changes.
The researchers studied 40 women with PTSD as a result of recent sexual assault trauma (within the past year), recruited from the Hospital Clinic of Barcelona, along with a matched control group. All underwent brain scans (via resting-state functional MRI) to look at brain connectivity, and how they relate to depressive and PTSD symptoms. Resting-state fMRI measures how different brain areas communicate with each other.
Lead researcher, Dr Lydia Fortea (of the Hospital Clinic, Barcelona) said
"PTSD following sexual assault tends to be especially severe and is often accompanied by higher rates of depression, anxiety, and suicidal thoughts. Despite sexual violence being one of the most widespread forms of trauma affecting women, most research on PTSD has focused on other types of trauma, such as war. This is one of the first, and certainly the largest, connectivity study to look at PTSD in sexual assault in teenagers and adult women.
We looked at how key brain regions involved in fear and emotion regulation synchronise with the rest of the brain in women with PTSD following sexual assault. We focussed on the fronto-limbic system, which plays a crucial role in regulating emotions and responding to threats
We found that in 22 of the 40 women with PTSD following a recent sexual assault, communication between the amygdala and the prefrontal cortex was effectively lost, dropping to zero or near zero. The amygdala helps process emotions like fear, and the prefrontal cortex, helps control and regulate those emotions. When this connection weakens, the brain might struggle to manage fear responses or regulate emotions, which could explain why people with PTSD often experience intense fear and mood changes.
However, we didn't find that this brain change was directly linked to how severe their PTSD and depressive symptoms were. This suggests that while this brain difference might be a feature of the disorder itself, it's not necessarily a sign of how bad the symptoms are; this is probably dependent on other factors.
This supports the idea that PTSD after sexual assault is linked to problems in brain circuits that regulate emotion and fear. One of the things we will do now is to see if these connectivity disruptions following a sexual assault could help to predict response to PTSD treatment. If so, we would be able to identify early which patients are at risk of worse outcomes and intensify clinical efforts to help them recover. So far, this is a study of 40 women, but the work is ongoing. We need more studies to confirm the findings".
Commenting, Dr Marin Jukić (from the Karolinska Institute, Stockholm, and the University of Belgrade, Serbia) said:
"This study demonstrates profound fronto-limbic dysconnectivity in women with PTSD following sexual assault, a population historically underrepresented in brain connectivity research. The finding that amygdala–prefrontal communication can drop to near zero underscores the severity of circuit-level disruptions in emotional regulation networks after trauma. Notably, the absence of a direct correlation with symptom severity suggests that these connectivity deficits may serve more as a biological signature of the disorder rather than a state-dependent marker. This raises the possibility that such disruptions could become predictive biomarkers for treatment response, guiding personalized interventions. However, larger longitudinal studies are needed to determine how these neural patterns evolve and whether targeted therapies can ameliorate connectivity".
This is an independent comment, Dr Jukić was not involved in this work.
Notes
What is PTSD? (from the World Health Organisation)
