Vocal acoustic features may be objective biomarkers of negative symptoms in schizophrenia: A cross-sectional study

There are currently no objective biomarkers that allow the quantification of negative symptoms of schizophrenia. This study therefore explored the use of acoustic features in identifying the severity of negative symptoms in patients with schizophrenia. We recruited 79 inpatients who were diagnosed with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (the schizophrenia group) at the Huilongguan Hospital in Beijing, China, and 79 healthy controls from the surrounding community (the control group). We assessed the clinical symptoms of the patients with schizophrenia using the Positive and Negative Syndrome Scale (PANSS) and the Brief Negative Symptom Scale (BNSS) and recorded the voice of each participant as they read emotionally positive, neutral, and negative texts. The Praat software was used to analyse and extract acoustic characteristics from the recordings, such as jitter, shimmer, and pitch. The acoustic differences between the two groups of participants and the relationship between acoustic characteristics and clinical symptoms in the patient group were analysed. There were significant differences between the schizophrenia and control groups in pitch, voice breaks, jitter, shimmer, and the mean harmonics-to-noise ratio (p