Clinical studies on event-related potentials (ERPs) N400 and the related factors in patients with poststroke depression (PSD).

Objective: To evaluate event-related potentials (ERPs), N400, and the related factors in patients with poststroke depression (PSD).

Methods: Eighty-five stroke patients with depression, conforming to the diagnoses standard of Chinese Classification of Mental Diseases (3rd edition) (CCMD-3), were treated with fluoxetine hydrochloride for 3 months and another 85 stroke patients without depression were selected as the control group. The traits about N400 and blood platelet 5-HT concentrations of all patients were measured.

Results: There were significant differences between the incubation periods and average amplitudes of N400 in patients with PSD and those in patients without PSD (p < 0.01), while the blood platelet 5-HT concentrations of PSD patients were much lower than those of the patients without PSD (p < 0.01). For PSD patients, the N400 incubation periods were significantly shortened, averaged amplitudes were significantly increased (p < 0.01), and the blood platelet 5-HT concentrations were significantly raised after 3 months' treatment.

Conclusions: For ERPs N400 in PSD patients, the incubation period is significantly prolonged and the average amplitude is reduced. Blood platelet 5-HT concentration may influence ERPs N400 in PSD patients.

Significance: N400 detections are helpful to the early diagnostic of PSD, and provide objective electrophysiology indexes for follow-up visits.