Alzheimer's Disease, Measures of Neuropsychiatric Symptoms, and Nature Based Interventions
An article published in Healthcare (Basel) brought awareness to the the role of environmental modifications and design in mitigating behavioral symptoms by implementing nature based interventions to address the psychosocial needs of individuals with dementia. This study investigates various nature-based interventions for reducing agitation, anxiety, depression, and apathy in people with dementia in long-term residential care environments (Lee, 2025).
→ Behavioral symptoms can manifest in the incongruence between individuals’ needs or excessive stressors and the environment.
→ Modifying the environment to accommodate the needs of patients could be an effective strategy to counteract behavioral symptoms and reduce stressors.
→ Sensory gardens and outdoor natural environments were found to provide support towards positive emotions, an understanding of self and identity, reduced agitation and restlessness, increased social engagement, enhanced cognitive functions, and an improvement in depressive symptoms and quality of life.
→ The authors indicate a need for more research within the field of Neuroscience to understand the experience of nature based interventions impact on neuropsychiatric symptoms; to better understand how NBI intervention settings (indoor vs. outdoor), the presence of social interaction, the types of experiences with nature (indirect vs. direct), and the duration of interventions contribute to the variability in the effects on individuals quality of life and health.
Major national research centers
The U.S. National Institute on Aging (NIA) and the Alzheimer's Association provide major funding and infrastructure for Alzheimer's research, including on environmental and lifestyle factors.
NIA-funded Alzheimer's Disease Research Centers (ADRCs): This network of centers across the United States investigates a wide range of dementia-related topics. Their projects may include research into how residential environments, such as green spaces, affect cognitive function.
National Exposome Research: NIA-funded researchers are exploring how environmental factors, including green space exposure, affect dementia risk. For example, some studies found that living near green spaces correlates with better cognitive function in older adults.
Universities and academic institutions
Harvard University: Research fellow Jochem Klompmaker led a major study examining the link between living in areas with more green and blue spaces and the slowed progression of neurodegenerative diseases, including Alzheimer's.
Stanford University: Research led by Katrin Andreasson is studying how environmental factors, specifically the exposome, influence brain health and may offer pathways to improve brain function.
University of Southern California: Researchers from this and other universities are using large-scale databases, like the UK Biobank, to study links between outdoor activity, residential green space, and dementia risk. Their findings indicate outdoor physical activity, especially in green spaces, is linked to a lower dementia risk.
Changi General Hospital (Singapore): In collaboration with academia, the hospital is conducting a pilot study on personalized, guided Nature-Based Therapy for elderly inpatients with dementia and their caregivers.
Specific research focus areas
Horticultural therapy and garden spaces: Numerous studies have investigated the impact of gardens and horticultural activities.
Researchers Gonzalez and Kirkevold reviewed 16 studies that found gardening and sensory garden visits reduced agitation and restlessness while improving social engagement and well-being for people with dementia. A recent meta-analysis of 29 studies confirmed that nature-based interventions can significantly alleviate agitation in dementia patients in long-term residential care facilities.
Exposure duration and mood: A 2018 observational study from the UK found that exposure to nature gardens was associated with improved mood in patients with mid-to-late-stage dementia. The study suggested that even relatively short exposures of up to 90 minutes were beneficial.
Social interaction in nature: Research shows that nature-based interventions that include social interaction are more effective at reducing agitation. However, the ideal level of social interaction can vary among individuals and requires further study.
Aromatherapy: Some studies have looked at specific natural-based therapies. Clinical trials have explored the use of essential oils to improve neuropsychiatric symptoms in people with dementia.
Reference
Choe, E. Y., Lee, J. Y., & Montayre, J. (2025). Effectiveness of Nature-Based Interventions in Reducing Agitation Among Older Adults with Dementia: A Systematic Review and Meta-Analysis. Healthcare (Basel, Switzerland), 13(14), 1727. https://doi.org/10.3390/healthcare13141727
