Trauma experienced early in life has been linked to anxiety, depression, obesity, and substance abuse later on. Researchers examining the brain scans of 64 teenagers now say that these and other psychiatric disorders or risky behaviors may be the result of altered neural responses to both stressful and relaxing cues.
Previous neuroimaging studies have associated childhood maltreatment with abnormalities in certain brain regions, but these studies have been both too generic and limited. So, Yale’s Marc Potenza and colleagues examined functional magnetic resonance imaging (fMRI) data for 40 boys and 24 girls between 14 and 18 years old with varying exposure to maltreatment-related trauma. This ranged from prenatal cocaine exposure to abuse and neglect. In particular, the team wanted to see which brain regions were activated in response to individually tailored stimuli: personally relevant stress, favorite foods, and neutral and relaxing scenarios (like sitting in the park or unwinding in your own room).
The team found that, compared to the low-trauma group, participants in the high-trauma group showed greater activation in several cortical regions in response to stress (pictured above). These areas showing “hyper-responsivity” to stress cues have important roles in emotional regulation. As for the neutral or relaxing cues, the high-trauma group showed a significantly decreased activation in the cerebellar vermis and right cerebellum. With their roles in processes like regulating arousal, this decreased activation might reflect diminished self-control. The two groups didn’t show significant differences in their responses to favorite-food cues.
The work indicates that “youth exposed to higher levels of trauma may experience different brain responses to similar stressors,” Potenza tells Reuters. “These findings suggest the possibility that there might exist different sensitivities to the relative allocation of brain resources to stressful stimuli in the environment and may hold multiple implications for prevention and treatment efforts.”
The findings were published in Neuropsychopharmacology last month.