Multisensory simultaneity-judgment training and speech comprehension in patients with schizophrenia

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Multisensory integration, aligning auditory and visual signals, is crucial for perception.
• Schizophrenia (SZ) patients exhibit abnormal temporal processing, with a wider temporal binding window (TBW), impacting speech comprehension.
• Audiovisual simultaneity-judgment training (SJT) shows promise for recalibrating temporal perception in healthy adults, but its efficacy in SZ is unproven.

Purpose of the Study:

• To investigate the efficacy of feedback-based audiovisual SJT in clinically stable schizophrenia patients.
• To assess SJT's impact on temporal perception (TBW), multisensory illusion susceptibility (SIFI), and speech-in-noise comprehension.
• To determine if SJT-induced changes in temporal processing persist over time.

Main Methods:

• Thirty clinically stable schizophrenia patients participated in three SJT sessions.
• Evaluated changes in simultaneity judgments, sound-induced flash illusion (SIFI) susceptibility, and word recognition in noise.
• Utilized mixed-effects models to analyze training-induced changes in temporal perception and speech comprehension.

Main Results:

• SJT significantly narrowed the temporal binding window (TBW) in SZ patients, a change sustained for two weeks.
• Improved simultaneity judgments correlated with enhanced word recognition in noisy conditions (audiovisual and auditory-only).
• No significant training effects were observed for the sound-induced flash illusion (SIFI).

Conclusions:

• Audiovisual SJT effectively recalibrates temporal perception in schizophrenia patients, narrowing their TBW.
• SJT demonstrates potential for improving speech comprehension in challenging auditory environments for individuals with SZ.
• This study provides initial evidence for SJT as a therapeutic intervention for audiovisual temporal processing deficits in schizophrenia.