Exposure to nature reduces negative emotions and boosts brain capital

You probably heard it from your mom a thousand times – fresh air and sunshine; it’s the cure for most anything. Now scientists at the University of Houston concur, measuring the impact of mother’s advice on mother nature to find that exposure to nature is associated with reductions in negative emotions. 

Given that nearly 90% of the U.S. population is projected to reside in urban areas by 2050, researchers say integrating nature into urban design and public health initiatives is an increasingly recognized national public health and economic priority for improving emotional wellbeing. 

Findings from this systematic review support the notion that nature exposure is a critical determinant of brain health and therefore brain capital. Thus, promoting and maintaining healthy environments is critical to promote and grow the world’s brain capital.”

Jose Luis Contreras-Vidal, renowned brain scientist, Hugh Roy and Lillie Cranz Cullen Distinguished Professor of Electrical and Computer Engineering and director, NSF IUCRC BRAIN Center (Building Reliable Advances and Innovation in Neurotechnology)

He led a team of researchers through a systematic review and meta-analysis of the impact of nature on wellness. 

The team examined the results from 2,101 participants in 33 studies combining neuroimaging and psychological assessments during exposure to real, virtual or imagined natural environments. EEG was the most widely used neuroimaging modality across the studies reviewed. 

“Healthy populations showed a more balanced psychological response, with nature exposure being associated with both increases in positive emotions and reductions in negative emotions,” reports Contreras-Vidal in the International Journal of Environmental Research and Public Health. “Growing interest in how nature influences the brain has driven research toward understanding its neurophysiological impact. This interest has recognized that genetics alone cannot account for health risk factors and that environmental exposures play a substantial role in shaping brain health.” 

The team examined brain studies that included several different tasks: 

• Imagery: The most popular task across studies, images of nature consistently demonstrated significant effects of nature on well-being. Eight studies reported increases in positive emotions while seven observed decreases in negative emotions. 

• Virtual Reality: Eight studies implemented VR-based exposure to nature, all of which used EEG as their neuroimaging modality. Six studies reported decreases in negative emotions and five reported increases in positive emotions. 

• Walking Outdoors: Five studies reported an increase in positive emotions and four reported decreases in negative emotions. 

While studies employing psychological and neuroimaging can potentially provide a shift in understanding of the neurophysiological impact of nature on brain health and wellness, there is still much to know, and Contreras-Vidal has suggestions. 

“EEG studies should expand their scope to incorporate neural metrics like functional connectivity, while prioritizing standardization of real-world multimodal data for study comparisons and effective inclusion of AI,” he said. 

“Ultimately, the goal is to design Nature prescriptions (Nature Rx) to promote brain health and treat mental illnesses across the lifespan,” said Contreras-Vidal. 

Based on the findings, the BRAIN Center is working on a study on the neural mechanisms underlying nature’s impact on brain health and wellness in Houston’s Third Ward neighborhood along the green corridor and on the UH campus’ pollinator gardens. 

This article was originally published on news-medical