The outcome of the research is the establishment of a relationship between a sizable neighborhood green space and a higher mental capacity. This was shown after researchers from the Barcelona Institute for Global Health studied 6,500 people based in the U.K. over the course of a ten year period.
Previous studies had established a connection between access green spaces and a beneficial effect on mental health. The new study goes further, drawing connection between green spaces and a positive role in reducing cognitive decline in the elderly. This is in relation to the type of reduction in cognitive function that forms part of the aging process.
Green spaces
Green space is an umbrella term, and one that does not have a common definition. The term describes either a maintained (like a park) or unmaintained (such as a nature reserve) environmental areas. The purpose of an open space reserve can extend to the preservation or conservation of a rural character.
Mental health
With mental well-being, research suggests that individuals who move home from a less green to a more green area show significantly better mental health, as measured across the three post-move years. Such study infers a sustained improvement in mental health. A related study has found that the size of the green space is a factor. Here local-area proportions of green space are associated with different degrees of mental well-being, as measured using the Warwick-Edinburgh Mental Well-Being Scale.
Cognitive function
Age-associated cognitive decline differs in extent between individuals and the determinants of the differences in age-related cognitive decline are not fully understood. As people get older, their cognitive abilities gradually deteriorate. A level of cognitive decline is a normal part of ageing. Some experience a severe deterioration in cognitive skills, leading to dementia. The focus of the recent study is on the age related decline in cognitive capacity that everyone is, or will, experience.
New research
With the new study, scientists studied 6,500 people, aged 45 to 68, over the course of ten years. The subjects were drawn from the Whitehall II cohort (a study into social inequalities and chronic disease with new clinical measures of cognitive function, mental disorders and physical functioning in relating to aging) in the U.K. Across three different time-points, during the course of the study, each subject completed a range of cognitive tests designed to assess their verbal and mathematical reasoning, together with verbal fluency and short-term memory. Any decline in these functions was assessed.
The study also took into account the access to neighborhood green space for each participant, based on satellite images. According to lead researcher Carmen de Keijzer: “Our data show that the decline in the cognitive score after the 10-years follow up was 4.6 percent smaller in participants living in greener neighbourhoods. Interestingly enough, the observed associations were stronger among women, which makes us think that these relations might be modified by gender.”
Given that the proportion of people over 60 years old in the world is expected to nearly double between 2015 and 2050, the scientists think their is merit in further study in order to address the factors associated with cognitive decline. The new research is published in the journal Environmental Health Protection, with the research paper called “Residential Surrounding Greenness and Cognitive Decline: A 10-Year Follow-up of the Whitehall II Cohort.”
Essential Science
This article is part of Digital Journal’s regular Essential Science columns. Each week Tim Sandle explores a topical and important scientific issue. Last week we considered just how big the periodic table could potentially become. This was in relation to most recent four elements incorporated: nihonium, moscovium, tennessine, and oganesson.
The week before we looked at a new compound called ‘f-sand’, which has a botanical component. The material has the potential to be used a means to provide clean water to low income countries.
