Bottom-Up Virtual Nature Versus Top-Down Guided Imagery in Hospitalized Older Adults: A Randomized Parallel-Group Clinical Trial
Long hospital stays can be difficult for older adults. Being confined to a ward, with limited mobility and little access to the outdoors, may contribute to anxiety, low mood, and reduced well-being. Contact with nature is known to support relaxation and emotional recovery, but hospitalized patients often cannot go outside. This study compares two ways of bringing a nature experience to patients who are staying in hospital. In the first approach, participants wear a virtual reality headset and watch 360-degree videos filmed in real natural settings near Budapest: a meadow, a stream, and a mountain. The nature scene reaches them through their eyes and ears. In the second approach, participants listen to a short recorded audio guide and picture the same three nature scenes in their own minds, with their eyes closed. Here the nature scene is created by their own imagination. Both approaches use exactly the same nature themes. The only difference is how the experience reaches the person: from the outside through the senses, or from the inside through imagination. The study asks whether these two routes have different effects, and whether they can be told apart by measuring heart rate variability, which reflects how the body's automatic nervous system responds. Participants are adults aged 65 or older who have been in hospital for at least two weeks. After joining the study, each participant is first observed for two weeks while receiving only their usual hospital care. This period serves as their own comparison. They are then assigned by chance to one of the two approaches and take part in three sessions over two weeks. Questionnaires and brief cognitive tests are completed at three points: when joining, before the sessions begin, and after the sessions end. The main question is whether anxiety symptoms decrease more during the session period than during the preceding period of usual care. The study also looks at mood, attention and memory, well-being, and resilience.
This is a prospective, two-arm, parallel-group randomized controlled trial conducted at two clinical sites of Semmelweis University: the Department of Geriatrics and Nursing Science, and the Department of Rehabilitation Medicine. A distinctive feature of the design is that all participants undergo an observation period of equal length under treatment as usual before randomization, so that each participant serves as their own control for the pre-intervention period. This allows the change observed during the intervention period to be distinguished from time-dependent processes occurring during hospitalization itself. This design was chosen because neither a waiting-list control nor a no-treatment condition was considered ethically acceptable in this population. Participants are enrolled after approximately two weeks of hospitalization (T0). A two-week observation period under usual care follows, during which a single resting heart rate variability recording is obtained. The T1 assessment is conducted at the end of this period, followed by randomization and three intervention sessions delivered over two weeks. The T2 assessment follows the intervention period. No follow-up assessment is conducted. The two arms differ only in the processing route. The virtual reality arm delivers the natural environment as bottom-up perceptual input via a head-mounted display, using proprietary 360-degree videos recorded from a fixed tripod perspective at three locations near Budapest. The videos contain no narration or added music, only the natural soundscape of the location. The guided imagery arm delivers the same content as an internally generated, top-down process, using a standardized audio recording that begins with a brief breathing relaxation followed by the motif text. Both arms use identical standardized symbolic nature motifs (meadow, stream, mountain) drawn from the motif repertoire of Katathym Imaginative Psychotherapy. The design therefore does not compare an active intervention with a passive control, but two content-equivalent interventions that differ in their processing pathway. Two primary outcomes are specified. The primary clinical outcome is the change in anxiety symptoms between T1 and T2. The primary mechanistic outcome is RMSSD recorded during the intervention sessions, computed from a five-minute artifact-free window in both arms. Heart rate variability is recorded in three contexts: once at rest during the observation period, during each intervention session, and during neuropsychological testing at each assessment point. Because hospitalized older adults frequently present with multimorbidity and complex medication regimens, clinical background variables that may affect autonomic regulation and cognitive performance are systematically recorded, including pacemaker status, sympatholytic and psychotropic medication, endocrine conditions, and clinically relevant laboratory abnormalities. The protocol was prepared in accordance with the SPIRIT 2025 Statement. Registration was performed retrospectively, after enrollment of the first participant. The trial design, including all primary and secondary outcome measures and the statistical analysis plan, was finalized and approved by the research ethics committee before enrollment began, and registration preceded any analysis of outcome data.
Inclusion Criteria: * Aged 65 years or older * Receiving inpatient hospital care, with at least two weeks of hospitalisation at the time of enrolment * Montreal Cognitive Assessment (Hungarian version) score of 18 or above, with education correction * Physically able to safely wear a head-mounted virtual reality display * Adequate corrected or uncorrected vision and hearing * Able to communicate in Hungarian * Stable psychiatric and cardiovascular condition, as determined from medical history and in consultation with the treating physician * Able to provide independent written informed consent
Exclusion Criteria: * Epilepsy with recurrent seizures, or photosensitivity * Neurological condition associated with increased risk during virtual reality use, including Meniere's disease and significant carotid stenosis * Active psychosis, hallucinations, or severe depression with psychotic features * Open wound or skin lesion on the face, chronic neck pain, or spinal condition preventing safe use of the head-mounted display * Severe uncorrectable sensory impairment * Unstable psychotropic medication during the preceding eight weeks * Regular use of analgesic or psychotropic medication that may substantially affect perception of the experience * Active alcohol or substance use disorder within the past year * Refusal or inability to provide informed consent Enrolment is deferred, rather than excluded, in the presence of active delirium or infectious illness, until the condition resolves.
[{"measure":"Change in anxiety symptoms (HADS-A)","timeFrame":"Baseline, Week 2, and Week 4"},{"measure":"Heart rate variability during intervention sessions (RMSSD)","timeFrame":"Week 2 through Week 4"}]