A new study published in Brain Imaging and Behavior searches for the potential relationship between childhood trauma, social anhedonia, and brain gray matter volume. The research found individuals with moderate to severe childhood trauma experienced higher levels of social anhedonia and exhibited differences in gray matter.
The consequences of childhood trauma have been of significant interest to researchers in the last few decades. It has been found to be a risk factor for mental disorders like schizophrenia and depression. These disorders are also related to differences in gray matter compared to healthy individuals.
Social anhedonia is a condition where individuals experience little pleasure in social interactions diminishing contact with friends and family. Social anhedonia has been found to be a symptom of both depression and schizophrenia. Examining all three factors may clarify what predisposes individuals to develop depression or schizophrenia.
The researchers recruited 43 healthy individuals who reported moderate to severe childhood trauma and 68 others with little to no childhood trauma. Levels of childhood trauma were determined using the Childhood Trauma Questionnaire. Subjects also completed the Revised Social Anhedonia Scale and the Beck Depression Inventory. In addition, gray matter was measured using a magnetic resonance scanner.
Analysis of this data collection found that the experimental group (those with high levels of childhood trauma) had much higher levels of social anhedonia than the control group. There was no difference between the groups in levels of depression. The brain scans revealed that those with childhood trauma had specific areas of the parietal, temporal and occipital lobes that were larger than the control group.
Specifically, “results showed that the volume in the left inferior parietal lobule (IPL) and right dorsolateral prefrontal cortex (DLPFC) were significantly correlated with social anhedonia.” This was true across gender, age, and IQ scores. These two areas, the IPL and DLPFC, have previously been implicated in social activities.
The findings are aligned with previous studies finding that those with social anhedonia have abnormalities in those social areas of the brain. The research team states “the results of our mediation model support our proposal that childhood trauma may be linked to social anhedonia via brain structure within regions known to support social cognition.”
Limitations include the self-report model for assessing childhood trauma. In addition, participants must consider their childhood retrospectively, and possible errors could occur. Another limitation includes the use of healthy subjects, subjects with childhood trauma who had also developed schizophrenia or depression may yield different results. Third, the research design was cross-sectional, and there may be confounding differences between the participants that could have skewed the results.
Despite this, the researchers feel they may have made a meaningful contribution to understanding the consequences of childhood trauma and the factors that may make someone vulnerable to social anhedonia and possibly depression or schizophrenia.
The study, “Childhood trauma is associated with social anhedonia and brain gray matter volume differences in healthy subjects”, was authored by Jie Fan, Wanting Liu, Jie Xia, Feng Gao, Chuyi Meng, Yan Han, Huan Zhou Jinyao Yi, Changlian Tan, and Xiongzhao Zhu.
