High-Frequency Oscillations in Schizophrenia

Abstract

Neural oscillations and their synchronization may represent a versatile signal to realize flexible communication within and between cortical areas. There is extensive evidence that cognitive functions depending on coordination of distributed neural responses are associated with synchronized oscillatory activity, suggesting a functional mechanism of neural oscillations in cortical networks. In addition to their role in normal brain functioning, there is increasing evidence that altered oscillatory activity may be associated with certain neuropsychiatric disorders, such as schizophrenia, that involve dysfunctional cognition and behavior. In the present paper, the focus is on the role of high-frequency oscillations for cortical computations through establishing correlations between the modulation of oscillations in the beta/gamma frequency range and specific cognitive processes during normal brain functioning and in schizophrenia. Specifically, it is suggested that in addition to oscillations in the low (30-60 Hz) gamma-band range, gamma-band oscillations > 60 Hz may have a crucial role for the understanding of cognitive dysfunctions in schizophrenia. Perspectives for future research will be discussed in relationship to methodological issues, the utility of neural oscillations as a biomarker and the neurodevelopmental hypothesis of schizophrenia.

GluN2D N-Methyl-D-Aspartate Receptor Subunit Contribution to the Stimulation of Brain Activity and Gamma Oscillations by Ketamine: Implications for Schizophrenia

“…Neuronal oscillations in the gamma frequency band are thought to be integral to cognition and perception, and their impairment has been proposed to underlie the symptoms of schizophrenia (Gonzalez-Burgos and Lewis, 2008;GonzalezBurgos et al, 2010;Uhlhaas and Singer, 2013). Because NMDARs in PV cells are important for the modulation of gamma oscillations (Carlen et al, 2012;Uhlhaas and Singer, 2013), these results are also consistent with a key role of GluN2D subunits in cortical PV cell function. In addition, GluN2D subunits in the thalamus are likely to contribute to ketamine-induced dysrhythmias.…”

“…Schizophrenia and chronic blockade of NMDARs during development (Wang et al, 2001) are associated with an altered excitatory/inhibitory balance, reduced PV expression, and disturbed gamma oscillation modulation (Lisman et al, 2008;Kantrowitz and Javitt, 2010;Uhlhaas and Singer, 2013). If GluN2D-containing NMDARs contribute to the excitatory/inhibitory balance during development, one might expect similar defects in the adult GluN2D-KO mouse as seen in schizophrenia or after chronic NMDAR blockade.…”

“…These effects could also be mediated by PV-containing interneurons in the thalamic reticular nucleus (Frassoni et al, 1991;Llinas et al, 2005). In schizophrenia, NMDAR-hypofunction may thus disturb excitatory/ inhibitory balance, thereby altering neuronal oscillations and disrupting cognitive function (Lisman et al, 2008;Kantrowitz and Javitt, 2010;Uhlhaas and Singer, 2013).…”

Disruption of Neurosynaptic Physiology and Neuron Network Dysfunction in Brain Disorders: An Environmental and Occupational Health Perspective

“…Tasks that involves working memory is associated with increased EEG synchronization especially, in the theta band and possibly also in alpha band. Gamma band synchronization is important neurophysiological mechanism underlying binding, attention and even cociousness [84][85][86][87]. Charecteristic "fragile binding" of dynamic synchronization can be disturbed in two ways.…”

Cellular and Circuit Models of Increased Resting State Network Gamma Activity in Schizophrenia

“…Gamma oscillations are correlated with cognitive processes such as perception, attention, memory, and consciousness (Engel et al, 1997;Howard et al, 2003;Gregoriou et al, 2009;Herrmann et al, 2010;Panagiotaropoulos et al, 2012) In disease states these fast frequency brain oscillations are often perturbed when compared to control subjects (Uhlhaas and Singer, 2013). Furthermore, different aspects of gamma oscillatory activity are thought to be pertinent to abnormal brain activity and perhaps the pathophysiology of various disorders.…”