Juran, S., Oknina,L., Oades, R. D., Torres, R., Herwig, K., Weisbrod, M. (a), Chan, E., Chen, E. Y. H. (b), and Röpcke, B., (2004).
Brain sources for change detection: An ERP-study in patients at the outbreak of early onset schizophrenia and 15-years later.Schizophrenia Research, 67, supplement, 129-130.

Biopsychology Group, University Clinic for Child and Adolescent Psychiatry, Essen, Germany: Oades@uni-essen.de. (a) University Psychiatry Clinic, Heidelberg, Germany, (b) Queen Mary Hospital, University of Hong Kong, PRC

.Introduction: Severer illness, poorer prognosis and impaired brain structure are reported for patients with an early-onset of schizophrenia (Ref. 1 & 2). Is this reflected in early stimulus processing?

Methods: . This study compares an electrophysiological measure of automatic, auditory attention-related function and its sources in the brain for 19 patients (17.5 years) at onset, and 17 patients 15 years after an early onset with age-matched healthy subjects.
Mismatch Negativity (MMN), recorded from 32 sites during a simple visual vigilance task, was associated with a rare tone shorter than the standard.

Results:

First: Both patient groups showed a smaller MMN than the controls.

Second: Brain electrical source analysis (BESA) confirmed bilateral frontal and temporal lobe dipoles (Ref. 3).

Third: There were several signs of illness progression in the older patient group:
a) a visual vigilance decrement was only evident in the older patients,

b) the left superior temporal source was weaker,

c) the left cingulate source changed orientation,

d) the right inferior/mid frontal source was active later

Conclusions: This illness-related progression of a cognitive impairment is consistent with a neurodevelopmental hypothesis4, initial structural impairments in young patients (ref 4 & 5) contrasting with more variable or sporadic changes in those with a later onset (ref 6 & 7).

1. Röpcke et al. 2004 Europ Child Adolesc Psychiat in press
2. Collinson et al. 2003 Br J Psychiat 183, 114-120
3. Jemel et al. 2002 Brain Topog 15, 13-27 (Jemel et al., 2002)
4. Weinberger et al. 1997 Neuropsychopharmacol 14, 1-11
5. Jacobsen et al. 1998 Am J Psychiat 155, 678-685
6. DeLisi et al 1997 Psychiat Res (NI) 74, 129-140
7. Cahn et al 2002 Arch Gen Psychiat 59, 1002-1010

Dr. Oknina was supported by the Alfried Krupp von Bohlen und Halbach Stiftung