An overlap of clinical symptoms between major depressive disorder (MDD) and social anxiety disorder (SAD) suggests that the two disorders exhibit similar brain mechanisms. However, few studies have directly compared the brain structures of the two disorders. Dr. Youjin Zhao, from Prof. Dr. Qiyong Gong's research group at the Institute of Huaxi MR Research Center (HMRRC) of West China Hospital of Sichuan University discovered that the MDD and SAD shared a common pattern of gray matter abnormalities in the orbitofrontal-striatal-thalamic circuit, salience network and dorsal attention network. These consistent structural differences in the two patient groups may contribute to the broad spectrum of emotional, cognitive and behavioral disturbances observed in MDD patients and SAD patients. MDD patients showed disorder-specific involvement of the visual processing regions. SAD patients showed disorder-specific involvement of the precentral cortex. These findings provide new evidence regarding the shared and specific neuropathological mechanisms that underlie MDD and SAD. Their results were published in EBioMedicine, whose two leading brands are The Lancet and Cell Press. At the same time, Dr. Andreas Frick, from the Department of Psychology of Uppsala University, has commissioned a Commentary article on this paper. He commented that the paper by Zhao et al. (in press) represents a welcome contribution to the field by investigating two different aspects of brain structure in the same individuals and only including non-comorbid and treatment-naïve patients.
Imaging findings and post-mortem analyses have contributed to the understanding of biological pathophysiology and the underlying neural mechanisms of mental illnesses. Some authors have recently suggested that imaging may change the diagnostic structure in psychiatry. “Psychoradiology is a term that describes a growing intersection between the fields of psychiatry and medical imaging”, explains professor Gong, “In clinical scenario, this term indicates the use of radiologic approaches in psychiatric illnesses, spanning from diagnosis to planning and monitoring treatment. Analogous to the Psychosurgery of surgery for mental disorders, it is an emerging branch of radiology in close association with the neuroradiology for neurology.”
“With the advent of ‘big data’ and the exponential increase in IT processing power and speed, huge quantities of brain structure and function information are able to be collated,” said Su Lui, M.D. Ph.D., lead scientist on the project at the HMRRC. “We plan to integrate multimodal images to investigate correlations and differences between different imaging modalities. It is very likely a multimodal template for research in psychiatry will eventually guide ground level diagnosis and treatment of mental illness in the future.”