Global and Parallel Cortical Processing of Auditory Gamma Oscillatory Responses in Humans

Neural network dynamics underlying gamma synchronization deficits in schizophrenia

“…These results are strikingly consistent with a previous ECoG study by Tada et al., 46 which showed cortical surface levels of gamma-band ASSR in humans. They demonstrated prominent increases of gamma oscillations at the right primary auditory cortex (A1), right supramarginal gyrus and right supplementary motor area as well as moderate increases of activity at bilateral prefrontal gyri.…”

“…46 The current study, using novel and non-invasive EEG connectivity analyses may thus fill a gap between this study of patients with schizophrenia and the study of Tada et al using ECoG and potentially may converge with findings from animal models. 46,67 The present study supports the increasing use of temporally distinct ASSR time intervals in studies of patients with psychosis. In this context, early and later time intervals of gamma oscillation appear to reflect dissociable response intervals.…”

“…They demonstrated prominent increases of gamma oscillations at the right primary auditory cortex (A1), right supramarginal gyrus and right supplementary motor area as well as moderate increases of activity at bilateral prefrontal gyri. While the Tada et al 46 findings were from patients undergoing neurosurgical intervention for treatment refractory epilepsy, they nonetheless suggest that these gamma-band locations are critical generators of ASSR in humans, and thus may be loci responsible for abnormalities in schizophrenia or other impaired neuropsychiatric patient populations. 46 The current study, using novel and non-invasive EEG connectivity analyses may thus fill a gap between this study of patients with schizophrenia and the study of Tada et al using ECoG and potentially may converge with findings from animal models.…”

“…While the Tada et al 46 findings were from patients undergoing neurosurgical intervention for treatment refractory epilepsy, they nonetheless suggest that these gamma-band locations are critical generators of ASSR in humans, and thus may be loci responsible for abnormalities in schizophrenia or other impaired neuropsychiatric patient populations. 46 The current study, using novel and non-invasive EEG connectivity analyses may thus fill a gap between this study of patients with schizophrenia and the study of Tada et al using ECoG and potentially may converge with findings from animal models. 46,67 The present study supports the increasing use of temporally distinct ASSR time intervals in studies of patients with psychosis.…”

“…26,35,[37][38][39][40][41][42][43][44] Despite this interest, there is limited information in schizophrenia patients about how different brain regions coordinate, interact and produce ASSR deficits through the stimulus entrainment period. 45,46 Reports suggest the time course of ASSR may reflect distinct aspects of schizophrenia pathophysiology. Specifically, the 40-Hz ASSR is usually measured across a full 500 ms stimulation interval, with an early ~1-200 ms stimulus onset interval, and late ~300-500 ms maintenance interval 27,28 : both firstepisode as well as chronic schizophrenia patients have gamma-band ASSR deficits in early and later time intervals, but individuals at clinical high-risk for psychosis, showed deficits in only the later maintenance time interval.…”