In modern society, increasing attention has been devoted to mental health problems among adolescents, with anxiety and depressive disorders being particularly prevalent in this population. Evidence indicates that anxiety not only affects emotional states and daily quality of life but also has significant impacts on physiological health, including blood pressure and heart rate. At present, clinical treatment relies primarily on pharmacological interventions and cognitive behavioral therapy; however, these approaches are associated with limitations such as pronounced side effects and delayed onset of efficacy, which restrict their applicability in adolescents. Music and other structured sounds have been used since ancient times to alleviate negative emotional states such as tension and anxiety. Research has shown that listening to soothing music can reduce sympathetic nervous system activity while enhancing parasympathetic tone, thereby leading to a decrease in heart rate and an increase in heart rate variability (HRV). Owing to its gentle characteristics, low-intensity soothing music is considered effective in relieving stress, regulating emotional states, and exerting beneficial effects on physiological indicators.

In modern society, adolescent mental health problems have attracted increasing attention. Anxiety disorders, as one of the most representative manifestations, not only impair daily functioning and academic performance but may also exert profound effects on physiological health. In recent years, music therapy, as a non-pharmacological intervention, has demonstrated considerable potential in alleviating anxiety. The present study aims to investigate the effects of low-intensity soothing music on physiological indicators, including cerebral blood flow and heart rate, in adolescents experiencing anxiety episodes, using functional near-infrared spectroscopy (fNIRS). This research not only contributes to a deeper understanding of the mechanisms underlying music therapy but also provides a scientific basis for the development of more effective interventions for adolescent anxiety.

Using fNIRS, we will continuously monitor changes in cortical cerebral blood flow, as alterations in hemodynamic patterns can directly reflect the effects of music-based interventions. Heart rate, as another key physiological indicator, will be continuously recorded and analyzed throughout the experiment. By means of a wearable smart band, we will capture heart rate variability (HRV) as well as temporal trends in heart rate. These data will enable us to determine whether low-intensity soothing music can reduce heart rate levels and enhance autonomic nervous system balance in adolescents with anxiety. In addition, immediate changes in heart rate before and after music exposure will be evaluated to assess the short-term effects of the intervention.

Inclusion Criteria:

• Participants experiencing anxiety episodes were adolescents aged 18-25 years with a Generalized Anxiety Disorder-7 (GAD-7) score ≥ 5;
• Participants completed self-report symptom assessments via a digital mental health screening platform, alongside the collection of acoustic voice features, heart rate, and functional near-infrared spectroscopy (fNIRS) data;
• All participants were required to provide written informed consent;

Exclusion Criteria:

• History of major somatic illnesses, particularly those potentially associated with brain tissue alterations, such as hypertension, diabetes, or metastatic tumors; unstable physical conditions, including severe asthma; and a history of neurological abnormalities, including significant head trauma (loss of consciousness lasting more than five minutes), epilepsy, cerebrovascular disease, brain tumors, and neurodegenerative disorders;
• Somatic conditions that may induce mood disorder symptoms, such as multiple sclerosis or thyroid disorders;
• IQ below 70;
• Autism spectrum disorder (ASD) or pervasive developmental disorder (PDD);
• Participants with significant substance abuse or dependence within the three months preceding enrollment were excluded;
• Participants at high risk for suicide or with a prior history of suicide attempts were excluded;