Effects of Immersive Natural Sound Stimulation With the Spherison Device on Anxiety Symptoms: A Case Series

Anxiety disorders are highly prevalent and often associated with incomplete response, poor tolerability, or refusal of pharmacological treatments. Nonpharmacological interventions targeting stress-regulatory systems are therefore increasingly explored. We describe herein the clinical effects of immersive natural sound stimulation delivered via the Spherison device, based on Sound 6D technology, in patients with generalized anxiety disorder (GAD). We report a case series of three adults meeting DSM-5-TR criteria for GAD who refused or discontinued psychotropic medication. All participants underwent three weekly 30-min sessions of passive listening to immersive natural soundscapes using the Spherison device. Anxiety severity was assessed at baseline and during treatment using the Beck Anxiety Inventory (BAI), Hamilton Anxiety Rating Scale (HAM-A), and Clinical Global Impression (CGI). All patients showed a progressive and clinically meaningful reduction in anxiety symptoms across sessions. Improvements were observed on both self-reported and clinician-rated measures, with no adverse effects reported. Two patients remained clinically stable at 6-month follow-up. Immersive natural sound stimulation delivered through the Spherison device may represent a feasible and well-tolerated nonpharmacological intervention for anxiety symptoms. Although limited by the small sample size and uncontrolled design, these findings support further controlled studies to evaluate efficacy and underlying mechanisms.