Forest Therapy and Mindfulness for Highly Sensitive Persons

This is a multicenter, randomized, parallel-group interventional study in adults with high sensory-processing sensitivity confirmed using a validated instrument. Participants are randomized 1:1 to one of two study arms at study entry and remain in their assigned group for the duration of the study. Intervention delivery is standardized across participating sites through facilitator training and a predefined session manual. The experimental arm consists of structured sessions conducted in forest environments and includes guided walking, mindfulness-based practices, and structured sensory awareness activities, with facilitated group reflection. The active comparator arm consists of structured indoor group activities designed to match the experimental arm in duration, group interaction, and facilitator contact, without exposure to forest or outdoor natural environments. Study procedures and assessment schedules are predefined in the protocol and implemented in accordance with applicable ethical requirements and Good Clinical Practice guidelines.