Acoustic features of music differentially modulate anxiety through EEG gamma oscillations and prefrontal connectivity

University students may experience high levels of anxiety and depression, which can adversely affect their daily lives and academic performance and represent significant mental health conditions. Music therapy has been proposed as a promising noninvasive approach, but the role of specific acoustic features and their neural underpinnings remain unclear. In this study, we investigated the effects of tonality (major vs. minor) and timbre (piano vs. violin) on state anxiety. Seventy-four students were assigned to one of four intervention groups and passively listened to excerpts from Bach's works. Anxiety was assessed with the State-Trait Anxiety Inventory (STAI-S), and neural responses were recorded with EEG. Analyses included power spectral density of beta and gamma bands, EEG-based brain source localization analyses with standardized low resolution brain electromagnetic tomography (sLORETA), and Granger causality of directional connectivity. Results showed that major-key violin music elicited the strongest anxiety reduction among anxious participants. This effect was accompanied by gamma-band alterations, with Granger causality indicating that enhanced central-to-DLPFC connectivity predicted reductions in STAI-S scores, while dACC activation appeared as a concomitant effect. Beta and gamma oscillations further exhibited complementary properties, with gamma being more sensitive to music intervention and beta reflecting inter-individual stability. These findings will provide preliminary mechanistic insights into how elemental musical features can modulate anxiety.