Inattention in Bipolar and Unipolar Depression: Event-Related Potentials Associated with Performing a GoNogo Task

Abstract

Background: This study aimed to examine the changes in Nogo N2 and P3 amplitudes in patients with bipolar affective disorder (BD) or major depressive disorder (MDD) and in healthy controls (HCs). The association between attention and Nogo N2 and P3 changes was also investigated. Methods: The study included 30 participants with BD, 30 participants with MDD, and 30 HCs aged 19-60 years. They performed a GoNogo task while their electroencephalograms were recorded. Beck Depression Inventory and State- Trait Anxiety Inventory were used for evaluation. Furthermore, behavioral measures and GoNogo N2 and P3 amplitudes were compared between the three groups. Results: Patients with BD or MDD exhibited a significantly poorer performance in Nogo accuracy than the HCs. Patients with BD or MDD showed significantly lower Nogo N2 amplitudes at the frontal, fronto-central, and central electrodes than the HCs. In patients with BD or MDD, the Nogo N2 amplitudes at the frontal or fronto-central electrode were positively correlated with state of anxiety scores and inattention. Conclusion: These findings suggest that decreased Nogo N2 amplitudes in the frontal or fronto-central areas could be a biological marker for inattention during depressive episodes associated with BD or MDD.