Disconnecting from natural environments hinders cognitive function. Spending time outdoors is a critical factor for peak mental performance.
Emerging research in environmental neuroscience underscores the essential role of nature exposure in optimizing brain health.
Studies consistently link green spaces and moving water with stress reduction, improved mood, and decreased anxiety. However, a growing body of evidence reveals a further benefit: enhanced cognitive function. This encompasses all processes involved in knowledge and understanding, including memory, reasoning, problem-solving, and imagination. One study demonstrated that viewing a green roof for just 40 seconds led to fewer mistakes on a cognitive test compared to viewing a concrete roof.
Dr. Marc Berman, director of the Environmental Neuroscience Laboratory at the University of Chicago, investigated this phenomenon. Participants underwent a demanding cognitive test, followed by a 50-minute walk in either an urban setting or a natural park. Upon returning, they repeated the test.
“Performance significantly improved – by about 20% – after the nature walk, but not the urban walk,”
Dr. Marc Berman
Studies by environmental psychologist Prof. Kathryn Williams at the University of Melbourne reveal that the benefits of spending time in nature extend beyond improved test scores.
“Immersion in natural environments consistently enhances creativity.”
Prof. Kathryn Williams
A four-day hike with no technology resulted in a remarkable 50% increase in participants’ creativity as measured by the Remote Associates Test, a widely used tool assessing creative thinking, problem-solving, and insight. (In this test, subjects find a connecting word for three seemingly unrelated words, such as “Big, Cottage, Cake” with the answer being “Cheese”).
The biophilia hypothesis, proposed by American sociobiologist E.O. Wilson, suggests an evolutionary explanation. Human brains and bodies are optimized for functioning within nature, having evolved alongside it. Dr. David Strayer, a cognitive neuroscientist leading the Applied Cognition Laboratory at the University of Utah, acknowledges the logic behind biophilia.
“Our hunter-gatherer ancestors likely thrived due to heightened awareness of their natural surroundings. However, modern life, with its extensive infrastructure, presents a mismatch. We’re attempting to navigate a demanding, stressful world with brains still adapted to a hunter-gatherer lifestyle.”
Dr. David Strayer
While the challenges of the hunter-gatherer era are undeniable, Dr. Strayer highlights the mismatch between our evolved stress response and modern stressors.
“Most contemporary stress doesn’t necessitate a physical response, yet it triggers the same physiological reaction – increased cortisol, heart rate, and alertness. This can negatively impact memory, mood, attention, immune function, and cardiovascular health.”
Dr. David Strayer
Thankfully, exposure to nature activates the parasympathetic nervous system, responsible for our “rest and digest” state. This promotes feelings of calmness and well-being, fostering clearer and more positive thinking, akin to the experience on the tranquil harborside walk described earlier.
A recently proposed theory suggests oxytocin, the “bonding” hormone, might play a role. This hormone exerts powerful anti-stress and restorative effects when we’re surrounded by safe, calming, and familiar natural settings.
However, if the sole benefit of nature were improved mood, it would only impact those who find nature enjoyable. Those who resonate with Woody Allen’s sentiment, “I love nature; I just don’t want to get any of it on me,” wouldn’t experience cognitive enhancement. Fortunately, research by Dr. Berman and others indicates that improved mood isn’t a prerequisite for improved cognitive function.
Dr. Berman’s study involved participants walking in nature during various seasons.
“Even in January, with temperatures nearing zero and participants reporting minimal enjoyment from the walk, they still demonstrated improved performance on cognitive tests. Enjoying the nature exposure wasn’t necessary to reap the benefits.”
Dr. Marc Berman
Another explanation for the cognitive boost lies in Attention Restoration Theory (ART). Psychologists refer to the ability to maintain focus on a specific mental task while ignoring distractions (both external, like phones, and internal, like hunger) as “directed attention.” ART proposes that this ability is a finite resource.
Multitasking and the overstimulation of modern environments deplete brain regions responsible for focused attention, explains environmental psychologist Prof. Kathryn Williams. This results in decreased concentration, increased errors, and difficulty problem-solving.
“Nature, however, engages the brain in an effortless way, granting these areas a chance to rest and recuperate.”
Prof. Kathryn Williams
Natural environments, while rich in stimuli, capture attention indirectly and spontaneously. A bird’s movement or the sound of leaves crunching underfoot draws our focus in a gentle, effortless manner known as “soft fascination.” This state allows for the restoration of directed attention, which might explain the frequent bursts of inspiration I experience – recording voice notes or jotting down ideas – after spending time in nature.
Exciting advancements in neuroimaging, like electroencephalograms and functional magnetic resonance imaging (fMRI), offer researchers real-time glimpses into brain activity during nature exposure. fMRI technology utilizes BOLD (blood-oxygen-level-dependent) imaging to identify brain regions most activated by specific stimuli. Similar to muscles, active brain areas require more oxygenated blood. Studies reveal a decreased BOLD signal in the prefrontal cortex (critical for executive function) during nature exposure, suggesting a state of “rest” within this brain region. Conversely, urban scenes activate a wider range of brain regions, indicating greater effort required for processing.
A limitation of fMRI is the requirement for stillness, hindering the study of real-world nature experiences. This is why Dr. Berman is enthusiastic about his new tool, functional near-infrared spectroscopy (fNIRS).
“We have some understanding of the brain during strenuous activity. fNIRS, however, allows us to monitor brain activity through infrared light as participants walk through various environments, revealing whether the brain expends more or less effort.”
Dr. Marc Berman
The connection between nature and brain function is undeniable. However, researchers are now delving deeper to identify the specific elements within natural environments that promote optimal restoration. Studies suggest “higher-quality” environments, brimming with diverse bird and tree life, yield greater reductions in anxiety and improved mood compared to less species-rich areas. This finding might pose a challenge for residents of Britain, a nation facing significant environmental degradation.
Dr. Berman’s research focuses on the role of “perceptual features” within an environment.
“The cognitive benefits observed simply from viewing nature pictures piqued our interest. We wondered if specific aspects like fractals – self-repeating patterns found in snowflakes, ferns, or trees – straight or curved lines, and color saturation contributed to the restorative effect.”
Dr. Marc Berman
Fractals are known to induce “soft fascination.” Curved lines, such as those found in hills, paths, or rivers, offer another example.
“These natural features might be more easily processed by the brain due to our evolutionary history with them.”
Dr. Marc Berman
Urban environments, with their prevalence of hard edges, straight lines, and a scarcity of “softly fascinating” stimuli, are inherently less restorative. The constant barrage of additional stimuli – traffic noise, crowds, advertisements, sirens, social media notifications – further strains the brain’s resources. The potential benefits of incorporating these natural patterns in built environments – fewer hard lines, more curves, and increased fractal structures – are being explored theoretically. However, such a prospect raises concerns about potentially diminishing the importance of experiencing nature itself.
“Our goal isn’t to develop a ‘nature pill,'” Dr. Berman clarifies, referencing research demonstrating that exposure to “real-world” nature yields greater improvements in mood and cognitive performance.
“We’re examining why we design environments the way we do. Currently, efficiency reigns supreme. But we could be considering how to design built environments that promote optimal attention, high well-being, and cooperation – integrating natural elements into streets, offices, schools, and homes. Accessibility remains a concern, as not everyone has easy access to nature.”
Dr. Marc Berman
Regardless of accessibility, most people spend very little time in nature. A recent government survey revealed that a quarter of the population hadn’t visited a green or natural space in the past two weeks. However, a 2021 BMJ report indicated that increased contact with nature is associated with better cognitive function, including working memory, spatial memory, attention (visual and general), reasoning, fluency, intelligence, and even childhood intellectual development.
“This growing body of research is demonstrating a crucial point: for optimal brain health, spending time in nature isn’t a luxury, it’s a necessity.”
Dr. Marc Berman
Summary
- Prioritize at least 30 minutes
Cognitive neuroscientist David Strayer suggests this duration is necessary to observe measurable cognitive improvements. Extended exposure, as in a “three-day effect,” yields even greater benefits. - Disconnect to reconnect
Focusing on devices or wearing headphones hinders engagement with our surroundings. Put down the phone and embrace the natural world. - Timing is key
Studies indicate a cognitive boost lasting 30 minutes after leaving a natural environment. Consider strategically scheduling nature breaks before tackling mentally demanding tasks. - Venue selection matters
Not all nature is created equal. A sense of safety is crucial for positive experiences in nature, including attention restoration, stress reduction, and creative mind wandering. Additionally, a feeling of ‘being away’ – a psychological detachment from burdens – is important.”
