Superior temporal gyrus spectral abnormalities in schizophrenia

Department of Psychology, Beckman Institute Biomedical Imaging Center, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
Psychophysiology (Impact Factor: 2.99). 08/2008; 45(5):812-24. DOI: 10.1111/j.1469-8986.2008.00682.x
Source: PubMed


Considerable evidence indicates early auditory stimulus processing abnormalities in schizophrenia, but the mechanisms are unclear. The present study examined oscillatory phenomena during a paired-click paradigm in the superior temporal gyrus (STG) as a possible core problem. The primary question addressed is whether first click and/or second click group differences in the time-domain evoked response in patients with schizophrenia are due to (1) group differences in the magnitude of poststimulus oscillatory activity, (2) group differences in poststimulus phase-locking, and/or (3) group differences in the magnitude of ongoing background oscillatory activity. Dense-array magnetoencephalography from 45 controls and 45 patients with schizophrenia produced left- and right-hemisphere STG 50- and 100-ms time-frequency evoked, phase-locking, and total power measures. Whereas first click 100-ms evoked theta and alpha abnormalities were observed bilaterally, evoked low beta-band differences were specific to the left hemisphere. Compared to controls, patients with schizophrenia showed more low-frequency phase variability, and the decreased 100-ms S1 evoked response observed in patients was best predicted by the STG phase-locking measure.

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Available from: Jose M Cañive
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    • "Giraud & Poeppel, 2012). Another is that pathological oscillatory patterns in disorders such as autism (Coben, Clarke, Hudspeth, & Barry, 2008; Cornew, Roberts, Blaskey, & Edgar, 2012; Edgar et al., 2013; Gandal et al., 2010; Uhlhaas & Singer, 2007) and schizophrenia (Edgar et al., 2008, Gandal, Edgar, Klook, & Siegel, 2011) have raised interest in characterizing the role of such activity in both non-pathological and pathological language processing. "
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    • "This finding adds to the growing literature demonstrating oscillatory abnormalities in schizophrenia in relation to dysfunctional information processing (e.g. [16]–[19]) and their implications for neuroplasticity [20], [21]. "
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    • "Although N1b activity was localized, given the spatial resolution inherent in MEG (perhaps 3–5mm; Miller et al., 2007), M100 STG sources most likely reflect activity from multiple auditory areas in or near Heschl's gyrus. Finally, an examination of the time-frequency profile of 100 ms STG activity showed that one of the few exceptions to bilateral 100ms findings in the frequency domain was evoked low beta-band differences only in the left hemisphere (Edgar et al., 2008). Future examination of the relationship between low beta activity and STG structural measures is of interest. "
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