40-Hz Audiovisual Stimulation in Schizophrenia Spectrum Disorders

N/ACompletedNCT07782034

National Cheng Kung University55 enrolled

Overview

This randomized, sham-controlled trial evaluated the effects of 40-Hz binaural beat music (BBM) combined with 40-Hz rhythmic photic stimulation (RPS) in adults with schizophrenia spectrum disorders. A total of 55 participants with schizophrenia or schizoaffective disorder were randomly assigned to either the BBM plus RPS group or a sham control group. Participants received 20-minute sessions three times per week for 12 consecutive weeks, for a total of 36 sessions. The primary outcome was anxiety measured using the Beck Anxiety Inventory (BAI). Secondary outcomes included psychological distress measured using the Five-item Brief Symptom Rating Scale (BSRS-5) and global cognitive function measured using the Mini-Mental State Examination (MMSE). Electroencephalographic (EEG) relative power across delta, theta, alpha, beta, and gamma frequency bands was also assessed as an exploratory physiological outcome.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

SUPPORTIVE_CARE

Masking

SINGLE

Enrollment

Conditions

Anxiety

Interventions

Participants received simultaneous 40-Hz binaural beat music (BBM) and 40-Hz rhythmic photic stimulation (RPS). The BBM was generated using 200-Hz and 240-Hz carrier tones to produce a 40-Hz binaural beat and was embedded in relaxing music delivered through circumaural stereo headphones at 60-65 dB SPL. The RPS was delivered through glasses equipped with bilateral white LEDs producing a 40-Hz square-wave flicker with a 50% duty cycle and an illuminance of 400 lx. Participants received the combined auditory and visual stimulation for 20 minutes per session with their eyes closed, three times per week for 12 consecutive weeks, for a total of 36 sessions.

Sham groupOTHER

Participants in the sham group underwent the same session procedures as the intervention group but did not receive 40-Hz binaural beat stimulation or rhythmic photic stimulation. Participants wore circumaural stereo headphones and RPS glasses and listened to the same relaxing music for 20 minutes; however, the music contained no binaural beats, and the light-output module of the RPS glasses remained switched off so that no flickering light was delivered. The glasses were powered on with the power indicator illuminated to maintain a similar device appearance. Music tracks, sound volume, session duration, and environmental conditions were identical to those of the intervention group. Sessions were administered three times per week for 12 consecutive weeks, for a total of 36 sessions.

Eligibility

Sex: ALLMin age: 20 YearsMax age: 65 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: 1. Diagnosis of schizophrenia or schizoaffective disorder according to DSM-5 criteria, made by a board-certified psychiatrist at least 1 year prior to enrollment. 2. Age 20 to 60 years. 3. Stable psychiatric symptoms, with no adjustment of major psychotropic medications for at least 2 consecutive months. 4. No severe hearing impairment. 4\. Current participation in a day-care program, community rehabilitation center, or rehabilitation ward. Exclusion Criteria: 1. Acute illness episode or unstable physical condition. 2. History of epilepsy or risk of seizures. 3. Substance abuse. 4. Impaired or disturbed consciousness.

Outcomes

Primary Outcomes

Change in Anxiety Severity as Measured by the Beck Anxiety Inventory (BAI)

The Beck Anxiety Inventory (BAI) is a 21-item self-report measure used to assess the severity of anxiety symptoms. Each item is rated from 0 to 3, yielding a total score ranging from 0 to 63, with higher scores indicating greater anxiety severity. The primary outcome was the change in total BAI score from baseline to post-intervention.

Time frame: Baseline and within 2 days after completion of the 12-week intervention