Prefrontal Cortex Activation During Verbal Fluency Task and Tower of London Task in Schizophrenia and Major Depressive Disorder

Yilei Xiang; Yuan Li; Chang Shu; Zhongchun Liu; Huiling Wang; Gaohua Wang

doi:10.3389/fpsyt.2021.709875

Prefrontal Cortex Activation During Verbal Fluency Task and Tower of London Task in Schizophrenia and Major Depressive Disorder

Front Psychiatry. 2021 Oct 8:12:709875. doi: 10.3389/fpsyt.2021.709875. eCollection 2021.

Authors

Yilei Xiang¹, Yuan Li¹, Chang Shu¹, Zhongchun Liu¹, Huiling Wang^{1

2

3}, Gaohua Wang^{1

4}

Affiliations

¹ Department of Psychiatry, Renmin Hospital of Wuhan University, Wuhan, China.
² Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University, Wuhan, China.
³ Department of Psychiatry, Zhongxiang Hospital of Renmin Hospital of Wuhan University, Zhongxiang, China.
⁴ Hubei Institute of Neurology and Psychiatry Research, Renmin Hospital of Wuhan University, Wuhan, China.

Abstract

Background: Cognitive dysfunction is a common clinical feature of mental disorders. A number of functional near-infrared spectroscopy (fNIRS) studies have shown reduced prefrontal activation during the verbal fluency task (VFT) in schizophrenia (SZ) and major depressive disorder (MDD). However, no studies have examined and compared the brain activation patterns during the Tower of London (TOL), which is another classic, high-sensitivity executive function testing tool, in these two serious mental disorders. This study aimed to assess the characteristics of brain activation during the two different cognitive tasks in SZ and MDD patients. Methods: This study recruited 30 patients with SZ, 30 patients with MDD, and 30 demographically matched healthy controls (HCs). The hemodynamic changes of the prefrontal cortex (PFC) were measured using 32-channel fNIRS during performance of the TOL task and VFT task. Results: SZ patients showed poorer VFT performance than MDD patients and HCs, and the two patient groups showed poorer TOL performance than HCs. Compared to HCs, both of the patient groups exhibited a significant decreased activation in the extensive PFC. Particularly in certain channels in the dorsolateral PFC (DLPFC), SZ patients exhibited significantly decreased hemodynamic changes than the MDD patients. Conclusions: Patients with SZ and MDD have different levels of impairment in different cognitive domains and different patterns of brain activation during the two cognitive tasks. Further research is needed to determine the use of fNIRS for clinical evaluation and diagnosis.

Keywords: MDD; SCH; TOL; VFT; functional NIRS.