Application of evoked response audiometry for specifying aberrant gamma oscillations in schizophrenia

Masaya Yanagi,Satoshi Ozaki,Aki Tsuchiya,Fumiharu Hosomi,Osamu Shirakawa

doi:10.1038/s41598-021-04278-5

Masaya Yanagi, Satoshi Ozaki + Show 3 more

Open Access

https://doi.org/10.1038/s41598-021-04278-5

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Journal: Scientific Reports	Publication Date: Jan 7, 2022
Citations: 2	License type: open-access

Affiliation: Kindai University, Izumi City General Hospital

Abstract

Gamma oscillations probed using auditory steady-state response (ASSR) are promising clinical biomarkers that may give rise to novel therapeutic interventions for schizophrenia. Optimizing clinical settings for these biomarker-driven interventions will require a quick and easy assessment system for gamma oscillations in psychiatry. ASSR has been used in clinical otolaryngology for evoked response audiometry (ERA) in order to judge hearing loss by focusing on the phase-locked response detectability via an automated analysis system. Herein, a standard ERA system with 40- and 46-Hz ASSRs was applied to evaluate the brain pathophysiology of patients with schizophrenia. Both ASSRs in the ERA system showed excellent detectability regarding the phase-locked response in healthy subjects and sharply captured the deficits of the phase-locked response caused by aberrant gamma oscillations in individuals with schizophrenia. These findings demonstrate the capability of the ERA system to specify patients who have aberrant gamma oscillations. The ERA system may have a potential to serve as a real-world clinical medium for upcoming biomarker-driven therapeutics in psychiatry.

Highlights

Gamma oscillations probed using auditory steady-state response (ASSR) are promising clinical biomarkers that may give rise to novel therapeutic interventions for schizophrenia
The current study proposes an approach that uses an automated evoked response audiometry (ERA) system to specify individual patients with schizophrenia who have severely impaired 40-Hz gamma oscillations
These findings may serve to address the biological variability in schizophrenia patients as it relates to upcoming biomarker-driven therapeutics

Summary

Introduction

Gamma oscillations probed using auditory steady-state response (ASSR) are promising clinical biomarkers that may give rise to novel therapeutic interventions for schizophrenia. Gamma oscillations whose impairments are predominantly shown in the prefrontal cortex are promising clinical biomarkers that may address novel therapeutic interventions for s chizophrenia[1,2,3,4,5,6,7] These are neural, rhythmic fluctuations in the gamma frequency range (30–200 Hz) that are commonly captured by electroencephalogram (EEG) or magnetoencephalography[2,8]. Based on the findings of postmortem brain studies, the cortical parvalbumin-positive GABAergic neurons are impaired in the prefrontal cortex of patients with schizophrenia[1,17], and GABAergic compounds are challenged to compensate for the dysfunction of the GABAergic neurons in schizophrenia p atients[18,19,20]. To utilize the plausible availability of the ERA system, this study examined the detectability of impaired gamma oscillations in patients with schizophrenia using the ERA device with the 46-Hz AM-FM ASSR as well as an ASSR with a basic 40-Hz AM tone stimulation, (i.e., 40-Hz AM ASSR)

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