Brain Markers of Depression Vulnerability: the Case of Prefrontal Haemodynamic Response

Functional near infrared spectroscopy (fNIRS) offers a cheap and reliable tool to investigate prefrontal brain activation in the healthy and diseased human brain. As such, fNIRS bears great potential as a diagnostic tool for clinical practice. Research indicates that fNIRS, together with a relatively simple task to activate the prefrontal cortex, the so-called verbal fluency task (VFT), elucidates prefrontal dysfunction in major depressive disorder (MDD). This finding can potentially serve as an imaging marker for disease pathology, even when depressive symptoms are absent. Indeed, recent research also suggests prefrontal dysfunction in fully remitted MDD (rMDD). Prefrontal haemodynamic responses may therefore serve as a trait marker for MDD vulnerability.

This study aims to investigate the haemodynamic response in rMDD, healthy participants with increased MDD risk (HCr; having a 1st-degree relative with MDD), and low-risk healthy participants (HCnr; having no 1st-degree relatives with MDD) using fNIRS. The investigators hypothesize lower prefrontal reactivity in HCr compared to HCnr, and lowest prefrontal reactivity in rMDD compared to HCnr.

This study has the potential to elucidate the neuronal underpinnings of depression vulnerability in the absence of symptoms that are sometimes considered a confounding factor when it comes to studying the biological encoding of depression.