MRI-related anxiety is prevalent among cancer patients and frequently undermines imaging quality by inducing motion artifacts or causing premature examination termination. Safe, non-pharmacological supportive interventions have the potential to alleviate procedural anxiety, yet the underlying neurobiological mechanisms remain unclear. This study aimed to investigate the anxiolytic effect of a combined multisensory intervention integrating music therapy and aromatherapy during MRI procedures, and to further explore its potential neurophysiological mechanisms via autonomic nervous system monitoring and resting-state functional magnetic resonance imaging (rs-fMRI).

This study adopted a prospective, single-center, parallel-group randomized controlled trial design and was conducted at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, between April 2025 and April 2026. Eligible participants were randomly allocated to four groups in equal proportions to receive routine care, music therapy alone, aromatherapy alone, or combined music and aromatherapy interventions. All study interventions were delivered consistently throughout the pre-MRI waiting period and the formal MRI scanning procedure, while participants in the control group received only standard clinical care without additional supportive intervention.

Cancer patients frequently experience significant anxiety during MRI examinations. The confined scanning environment, persistent acoustic noise, and mandatory prolonged immobilization inherent to MRI protocols collectively induce intense procedural stress. Such anxiety commonly causes motion artifacts, impairs diagnostic image quality, and may lead to premature scan termination. Beyond compromising imaging efficiency and accuracy, MRI-triggered psychological distress aggravates the overall psychological burden of cancer patients and may perturb systemic neuroendocrine and immune homeostasis, potentially affecting long-term disease prognosis.

Procedural anxiety arises from dynamic crosstalk between central neural circuits and peripheral autonomic regulatory systems. Chronic stress in oncological populations hyperactivates sympathetic tone and the hypothalamic-pituitary-adrenal axis, driving neuroendocrine dysfunction and immunosuppression. Multiple core brain networks, including the default mode, salience, and executive control networks, govern anxiety processing, with disrupted functional connectivity closely linked to anxiety severity. Concurrent HRV and neuroimaging research further confirms that acute MRI stress distorts bidirectional communication between cortical emotional regulatory regions and subcortical autonomic control centers.

Complementary interventions have emerged as safe, scalable strategies for mitigating cancer-related psychological distress. The 2023 joint clinical guidelines from the Society for Integrative Oncology and the American Society of Clinical Oncology endorse music therapy and aromatherapy for relieving cancer-associated anxiety. Each modality exerts independent anxiolytic effects via distinct neural and physiological pathways. Preliminary clinical evidence suggests that combined auditory and olfactory multisensory interventions may yield superior anxiolytic outcomes compared with single-modality approaches during stressful medical procedures.

Current literature lacks systematic evidence regarding the synergistic neurobiological mechanisms of combined music and aromatherapy for MRI-specific anxiety in cancer patients. Existing studies predominantly rely on subjective psychological assessments without synchronized objective autonomic and brain network profiling. This prospective randomized controlled trial addresses these research gaps by adopting a multi-dimensional evaluation system to characterize the behavioral, physiological, and neural effects of integrated multisensory intervention, aiming to provide mechanistic evidence for standardized supportive care protocols in oncological imaging practice.

This prospective, single-center, four-arm parallel-group randomized controlled trial was conducted at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, from April 2025 to April 2026. The study protocol was ethically approved (SKSY-2024-480-03), implemented in strict accordance with the Declaration of Helsinki and CONSORT 2025 guidelines, and pre-registered in the National Medical Research Registration and Information System of China (MR-44-25-034307). All participants provided written informed consent prior to enrollment.

This study enrolled eligible adult oncology patients requiring routine clinical MRI examinations, with unified enrollment specifications formulated to ensure homogeneous study populations.

Standardized exclusion criteria were established to exclude populations that might compromise intervention safety, data authenticity and research credibility.

Eligible participants were equally randomized into four parallel groups (1:1:1:1 allocation): routine care control, single music therapy, single aromatherapy, and combined multisensory intervention. Randomization was performed via computer-generated random numbers with sealed opaque envelopes by an independent researcher blinded to recruitment, intervention delivery, and outcome evaluation.

Due to the sensory nature of the interventions, participant blinding was not achievable. However, all data analysts, neuroimaging processors, and clinical radiologists remained fully blinded to group allocation throughout the trial to minimize detection bias.

All intervention protocols were initiated during the pre-scan waiting phase and sustained continuously throughout the entire MRI scanning procedure.

Control Group: Participants received standard clinical MRI care and routine pre-scan guidance without additional supportive interventions, with continuous vital sign monitoring throughout the procedure.

Music Therapy Group: Based on standard care, participants received standardized pre-scan autonomic monitoring followed by continuous exposure to a validated soothing traditional Chinese pentatonic guzheng musical stimulus via MRI-compatible headphones throughout scanning.

Aromatherapy Group: With consistent pre-scan autonomic monitoring, participants received standardized lavender olfactory stimulation via a fixed collar absorbent pad during the entire MRI procedure, with natural breathing maintained throughout.

Combined MT + AT Group: Participants received synchronized music and aromatherapy multisensory stimulation, with both interventions initiated after baseline physiological stabilization and sustained across the full scanning process.

The selected musical stimulus features high melodic consonance and smooth pentatonic structure to avoid triggering physiological alert responses. Lavender essential oil was selected based on robust meta-analytic evidence for reliable anxiolytic efficacy, with its core volatile components modulating central nervous system activity via olfactory transduction pathways.

Inclusion Criteria:

• Aged 18 to 60 years
• Pathologically confirmed malignant tumor
• Require clinically indicated MRI examination
• Baseline HADS anxiety subscale score ≥ 8
• Able to understand study procedures and provide written informed consent

Exclusion Criteria:

• Severe cognitive impairment or preexisting neurological disorders that compromise neuroimaging data quality
• Confirmed olfactory or auditory dysfunction
• Known hypersensitivity to aromatic essential oils
• MRI contraindications (implanted metallic devices, severe claustrophobia) or unstable cardiovascular conditions
• Concurrent enrollment in other interventional clinical trials

Individual participant data (IPD) will not be shared externally to protect participants' privacy and comply with institutional ethical review board requirements. Raw MRI, HRV and questionnaire records contain identifiable sensitive clinical information, and relevant local privacy regulations prohibit the public release of individual-level raw data.