Unique Brain Activity and Development Patterns Found in Youths With PTSD
Unique Brain Activity and Development Patterns Found in Youths With PTSD
Researchers have identified unique characteristics of emotional processing in young people with post-traumatic stress disorder (PTSD), showing for the first time how that processing might be disrupted at different ages.
Publishing their findings online August 5th in Neuropsychopharmacology, were 2012 NARSAD Young Investigator grantee Ryan J. Herringa, M.D., Ph.D., of the University of Wisconsin School of Medicine and Public Health and Richard C. Wolf, a Ph.D. candidate at the university. Together they looked at brain activity during an emotion-related task in children aged 8 to 18, both with and without PTSD. The children with PTSD had experienced trauma such as sexual abuse, the death of a loved one, a physical accident, or witnessing violence.
The children viewed emotionally “threatening” and “neutral” pictures. During this task, the researchers used imaging to measure activity in brain regions associated in PTSD with an increased fear response and sense of threat. These regions include the amygdala, important for processing emotions; the dorsal anterior cingulate cortex (dACC), which helps to gauge threat levels; and the medial portion of the prefrontal cortex (PFC), crucial for dialing back fear responses and putting perceived threats in context.
The researchers found higher threat-related dACC activity in youths with PTSD, as well as weaker connections between the amygdala and mPFC. The findings suggest these brain regions contribute to the difficulty young people with PTSD have in assessing perceptions of threat. The study also found that amygdala-PFC connections followed a different developmental path for youths with PTSD. Whereas those connections were stronger at older ages in those without PTSD, the same connections grew weaker for children with PTSD as they aged. This may reflect a progressive weakening in the ability of the PFC to reduce fear.
Future research will need to check for the potential impact of symptoms of depression and anxiety as well as other factors, such as medication, that might influence age-based amygdala-PFC patterns in children with PTSD. Dr. Herringa and colleagues also note that brain activity during threat processing should be measured among youths who have lived through trauma but do not show PTSD symptoms.
