Abstract
Objective: Disturbances of information selection under high processing load might be a key feature predisposing to psychotic disorders. The N2pc component of the ERP is a specific measure of selective attention. It is unclear whether N2pc is altered under increased demands in patients with psychosis. Methods: Patients with schizophrenia, with bipolar disorder (n= 20 each), and age-matched healthy controls (n= 21) had to identify two targets (" T1" and "T2") in two different simultaneous rapidly presented series of letters. We assessed the target-evoked N2pc and P3 components and the visually evoked potentials (VEPs) evoked by the rapid stream. Results: T1 and T2 identification rates did not substantially differ between groups. However, T1- and T2-evoked N2pc components were reduced in both patient groups. VEPs were enlarged in response to the first stimulus of the fast series in healthy participants but not in patients. T2-evoked P3 was reduced in patients with schizophrenia only. Conclusions: Under high attentional load, neurophysiological mechanisms underlying visual selection are compromised in patients with psychosis. The lacking VEP increase to the first stimulus probably indicates deficient arousal. Significance: These deficiencies of attentional selection and arousal might enhance liability to psychotic symptoms under stressful conditions.
| Original language | English |
|---|---|
| Journal | Clinical Neurophysiology |
| Volume | 124 |
| Issue number | 5 |
| Pages (from-to) | 881-892 |
| Number of pages | 12 |
| ISSN | 1388-2457 |
| DOIs | |
| Publication status | Published - 01.05.2013 |
Funding
The authors are most grateful to Fred Rist, Institute of Psychology, Münster University, Germany, for his many constructive comments on an earlier version of this manuscript. Thanks are due to Kirsten Herold for her help in EEG recordings, to Andreas Sprenger and Peter Trillenberg for stimulating and encouraging discussions, and to Antje Burfeind, Philipp Klein, Dirk Reichel, and Dietmar Steege for help in recruiting patients. This research was funded by a grant in the “neuro-biomedicine” program of the state of Schleswig-Holstein to R.L. and R.V. Thanks are due to Christine Klein for leading the proposal package. K.S. was funded by grant Ve110/15-1 awarded from the Deutsche Forschungsgemeinschaft to R.V. None of the authors reports any biomedical financial interests or potential conflicts of interest. Appendix A
