A free association semantic task for fNIRS-based perinatal depression assessment.

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Perinatal depression (PD) significantly impacts maternal and infant well-being, yet objective assessment tools remain limited.
• Functional near-infrared spectroscopy (fNIRS) is an emerging non-invasive neuroimaging technique for depression assessment.

Purpose of the Study:

• To introduce and validate a novel Free Association Semantic Task (FAST) paradigm using fNIRS for assessing perinatal depression.
• To investigate the neural correlates of emotional processing in perinatal depression using fNIRS.

Main Methods:

• A 48-channel fNIRS system recorded brain activity over frontal and temporal regions during a FAST involving positive, negative, and neutral seed words.
• Participants generated dynamic concept chains, and brain activity (oxyhemoglobin changes) was analyzed in relation to PD severity.
• Comparison with a classical verbal fluency test (VFT) was performed.

Main Results:

• fNIRS during FAST with positive and negative seed words showed correlations with PD severity in the frontal region, differing from neutral words and VFT.
• Distinct frontal activation patterns correlated with PD severity for positive (right dorsolateral prefrontal cortex) and negative (right inferior frontal gyrus) seed words.
• Regression analyses confirmed that FAST with emotional seed words effectively explained PD severity.

Conclusions:

• The proposed FAST paradigm using fNIRS is a promising, objective tool for assessing perinatal depression severity.
• This method offers insights into the neural mechanisms underlying emotional processing in PD.
• fNIRS-based FAST provides a potential avenue for improved clinical evaluation of perinatal depression.