History of childhood trauma was linked to functional dysconnectivity in the brains of adults with major depressive disorder, even though brain imaging took place decades after trauma occurrence, according to results of a study with a large, multisite functional MRI dataset.
“Experiences of childhood trauma, including physical, sexual or emotional abuse, as well as physical or emotional neglect, have been found to be associated with the emergence and persistence of depressive and anxiety disorders,” Yvette I. Sheline, MD, director of the Center for Neuromodulation in Depression and Stress at the University of Pennsylvania, and colleagues wrote in Proceedings of the National Academy of Sciences. “However, neurobiological mechanisms underlying the dimensional symptoms of MDD remain unclear.”
Researchers compared network connectivity differences within and between resting-state networks in 189 patients with MDD and 39 controls using functional MRI data. Among patients with MDD, they also examined the connections between brain networks and clinical symptoms, such as depression, anxiety, personality, suicidality and experiences of childhood trauma using a 213 item-level survey.
Analysis indicated that compared with controls, major depressive disorder could be characterized by:
- lower within-network connectivity in three resting-state networks — the frontoparietal network, dorsal attention network and cingulo-opercular network;
- greater within-network connectivity in two intrinsic networks — the default mode network and salience network; and
- greater within-network connectivity in two sensory networks — the sensorimotor network and visual network.
The researchers also found significant abnormalities in connectivity between a number of these networks.
"These results suggest that resting-state network connectivity may point to some of the brain mechanisms underlying the symptoms of major depressive disorder,” Sheline said in a press release. “It may have the potential to serve as an effective biomarker, aiding in the development of depression biotypes and opening up the possibility of targeted diagnosis."
In adult patients with MDD, previous childhood traumatic experiences and current depression symptoms were linked to abnormal brain network connectivity, according to the findings. Furthermore, a network model of MDD described within- and between-network connectivity differences from controls in several key resting-state networks, such as the default mode network, frontoparietal network and attention and sensory systems.
"With estimates of approximately 10% of all children in the United States having been subjected to child abuse, the significance of child maltreatment on brain development and function is an important consideration," Sheline said in the release. "This study not only confirms the important relationship between childhood trauma and major depression, but also links patients' experiences of childhood trauma with specific functional brain network abnormalities. This suggests a possible environmental contributor to neurobiological symptoms." – by Savannah Demko
Disclosure: Sheline reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.