OBJECTIVE: There has been a convergence of models describing schizophrenia as a disconnection syndrome, with a focus on the temporal connectivity of neural activity. Synchronous gamma-band (40-Hz) activity has been implicated as a candidate mechanism for the binding of distributed neural activity. To the authors' knowledge, this is the first study to investigate "gamma synchrony" in first-episode schizophrenia. METHOD: Forty medicated first-episode schizophrenia patients and 40 age- and sex-matched healthy comparison subjects participated in a conventional auditory oddball paradigm. Gamma synchrony, time-locked to target stimuli, was extracted from an ongoing EEG. The magnitude and latency of both early (gamma 1: -150 msec to 150 msec poststimulus) and late (gamma 2: 200 to 550 msec poststimulus) synchrony were analyzed with multiple analysis of variance. RESULTS: First-episode schizophrenia patients showed a decreased magnitude and delayed latency for global gamma 1 synchrony in relation to healthy comparison subjects. By contrast, there were no group differences in gamma 2 synchrony. CONCLUSIONS: These findings suggest that first-episode schizophrenia patients have a global decrease and delay of temporal connectivity of neural activity in early sensory response to task-relevant stimuli. This is consistent with cognitive evidence of perceptual integration deficits in this disorder and raises the possibility that a breakdown in the early synchrony of distributed neural networks is a marker for the onset of schizophrenia.
OBJECTIVE: There has been a convergence of models describing schizophrenia as a disconnection syndrome, with a focus on the temporal connectivity of neural activity. Synchronous gamma-band (40-Hz) activity has been implicated as a candidate mechanism for the binding of distributed neural activity. To the authors' knowledge, this is the first study to investigate "gamma synchrony" in first-episode schizophrenia. METHOD: Forty medicated first-episode schizophreniapatients and 40 age- and sex-matched healthy comparison subjects participated in a conventional auditory oddball paradigm. Gamma synchrony, time-locked to target stimuli, was extracted from an ongoing EEG. The magnitude and latency of both early (gamma 1: -150 msec to 150 msec poststimulus) and late (gamma 2: 200 to 550 msec poststimulus) synchrony were analyzed with multiple analysis of variance. RESULTS: First-episode schizophreniapatients showed a decreased magnitude and delayed latency for global gamma 1 synchrony in relation to healthy comparison subjects. By contrast, there were no group differences in gamma 2 synchrony. CONCLUSIONS: These findings suggest that first-episode schizophreniapatients have a global decrease and delay of temporal connectivity of neural activity in early sensory response to task-relevant stimuli. This is consistent with cognitive evidence of perceptual integration deficits in this disorder and raises the possibility that a breakdown in the early synchrony of distributed neural networks is a marker for the onset of schizophrenia.
Authors: Aaron F Alexander-Bloch; Petra E Vértes; Reva Stidd; François Lalonde; Liv Clasen; Judith Rapoport; Jay Giedd; Edward T Bullmore; Nitin Gogtay Journal: Cereb Cortex Date: 2012-01-23 Impact factor: 5.357
Authors: Tony W Wilson; Olivia O Hernandez; Ryan M Asherin; Peter D Teale; Martin L Reite; Donald C Rojas Journal: Cereb Cortex Date: 2007-06-08 Impact factor: 5.357
Authors: Greg J Siegle; Ruth Condray; Michael E Thase; Matcheri Keshavan; Stuart R Steinhauer Journal: Int J Psychophysiol Date: 2009-12-11 Impact factor: 2.997
Authors: J D Bonita; L C C Ambolode; B M Rosenberg; C J Cellucci; T A A Watanabe; P E Rapp; A M Albano Journal: Cogn Neurodyn Date: 2013-09-04 Impact factor: 5.082