Distinct prefrontal cortex alterations in confirmed and suspected depression individuals with different perceived stress during an emotional autobiographical memory task: One fNIRS investigation

Background: Previous research showed that perceived stress was strongly linked to depression, little is known about the underlying neurological mechanism of different depression subtypes with different perceived stress, and there is currently no classification of stress-based subtypes of depression. This study aimed at using fNIRS to uncover the neuromechanism of confirmed and suspected depression with different perceived stress, hence providing neurobiological evidence for the classification of stress-based depression subtypes. It is a significant target for effective depression treatment.

Method: The study included 551 young adults: 256 healthy control individuals, 62 confirmed depression patients, and 233 suspected depression participants. A 53-channel fNIRS imaging system was used to gather the average oxyhemoglobin level in the PFC during EAMT.

Results: Compared with HC, confirmed and suspected depression group show significant lower hemodynamic activation in right frontal lobe of frame under high loss of control. Confirmed depression with high sense of tension had higher activation than with high loss of control in right dlPFC, while for suspected depression, the activation with high sense of tension was lower than with high loss of control in left broca's area (BA) and front polar cortex (FPC).

Conclusion: All perceived stresses were not equal in their impacts on different depression types. The confirmed and suspected depression were two different depression subtypes sharing distinct activation pattern under different perceived stress in PFC, which may be an important target for stress-linked psychopathology. Depression can be further classified precisely based on stress. fNIRS can provide neuroimaging evidence for classification of stress-based depression subtypes.