Your brain on nature

You reread the same sentence three times. You switch from one tab to another without really making progress. The day isn’t over, but it already feels as though there’s no space left in your head. So you decide to go outside: a few minutes under the trees, a walk in a park, a break by the water. When you return, your to-do list is still there, but you may feel less tense, more present, and able to see things with a little more perspective.

Many of us are familiar with this experience. It also interests researchers, who study how natural environments influence our attention, our mood, and certain physiological responses to stress.

The potential effects extend beyond the brain. Spending time outdoors also changes our exposure to light, our opportunities to move, and sometimes our interactions with others. Several mechanisms can therefore come together during a single walk.

Our environment is one of the factors that shape how our bodies function and recover. Understanding this relationship helps us give nature a more practical place in our everyday lives.

Changing pace to restore attention

Much of our day relies on directed attention: staying focused on a project, following a conversation, selecting useful information, and ignoring distractions. This takes effort, particularly when demands keep coming one after another.

Attention Restoration Theory proposes that certain natural environments offer a different way of engaging our minds. The movement of leaves, reflections on water, or passing clouds draw our attention without asking us to respond or make a decision. Researchers call this “soft fascination”: attention captured with little effort, which may allow directed attention to recover. Studies offer partial support for this theory, with results varying according to the abilities being assessed.

In a study by Berman and colleagues, a walk in a natural environment improved performance on a working memory task more than a walk in a city. Working memory allows us to hold information in mind and manipulate it: following a line of reasoning, organizing several steps, or doing mental arithmetic.

This offers a possible explanation for the sense of clarity we can feel after a break outdoors. By stepping away from screens and unfinished tasks, we also change the kinds of demands we are exposed to.

When thoughts take up less space

Mental fatigue can also come from what keeps going around inside our heads: a conversation we replay, a mistake we keep revisiting, or a worry we examine without moving forward. This repetition of negative thoughts, known as rumination, can occupy a large share of our attention.

In a small study published in 2015, healthy adults took a 90-minute walk in either a natural or an urban environment. After the nature walk, they reported less rumination. The researchers also observed decreased activity in the subgenual prefrontal cortex, a region associated with, among other things, negative self-focused thoughts and rumination. These changes were not observed after the urban walk.

This finding suggests that a change of environment can help us temporarily gain some distance from certain thoughts. Going outside can therefore provide a useful transition when we feel stuck on a question: leaving our desk, walking, looking elsewhere, and then returning to what actually needs our attention.

Mental recovery can also have a physiological dimension. In a trial involving 63 adults, a one-hour walk in nature was followed by decreased activity in the amygdala during certain tasks performed in an MRI scanner. This region is involved in processing emotional and threatening information. Its activity remained stable after the urban walk. The study therefore offers a clue as to how the environment might influence the circuits involved in the stress response. These findings still need to be confirmed in randomized studies.

From the brain to physical recovery

Stress activates a whole range of responses. The autonomic nervous system helps adjust heart rate, blood pressure, and many internal functions. Its sympathetic branch helps prepare us for action, while parasympathetic activity contributes to slowing the heart rate and supporting resting functions, among other things. These mechanisms continually adjust to what we do and perceive.

Research on shinrin-yoku, or “forest bathing,” explores this dimension. This Japanese practice involves spending time in a forest environment and engaging with its atmosphere through the senses.

Experiments conducted in 24 forests across Japan found lower pulse rates and blood pressure in young men in forest settings than in urban settings, along with heart rate variability indicators consistent with greater parasympathetic activity. Participants walked, but also spent time sitting and looking at the scenery.

These observations help explain why a break in nature can feel physically as well as mentally restorative. They also invite us to broaden our definition of time outdoors: sitting in a garden or looking at a landscape has a place alongside walking.

Daylight and our biological rhythms

Going outside exposes us to another essential signal: light.

Light received by the eyes tells our biological clock what time of day it is. This clock helps organize the sleep–wake cycle, along with many physiological rhythms. In a small experiment involving eight participants, a week of camping, with more natural light during the day and less artificial light in the evening, shifted the timing of melatonin secretion earlier and brought the biological clock closer into alignment with the natural day–night cycle.

On a larger scale, a study involving more than 400,000 UK Biobank participants found an association between more time spent in outdoor light during the day and several more favorable indicators of sleep and mood.

Contact with nature and daylight can therefore complement each other. A morning walk in a park combines a natural environment, movement, and a light signal for the biological clock. This also helps explain why going outside during the day can be worthwhile even without access to a large green space.

The heart and metabolism: overlapping effects

Research on green spaces also finds links with physical health. A meta-analysis bringing together 143 studies observed associations with lower diastolic blood pressure and a lower prevalence of type 2 diabetes, among other findings. Much of this evidence is observational, and the included studies vary considerably in their definitions of green space and the populations studied. Living conditions, physical activity, and neighborhood characteristics may contribute to the associations observed.

In everyday life, these connections take practical forms. A nearby park can make it easier to get outside. A pleasant route can encourage more walking. A walk with someone close to you can bring movement and social connection together.

When time outdoors replaces time spent sitting, movement brings benefits of its own. Trials show, for example, that short walking breaks repeated throughout the day can reduce post-meal glucose and insulin responses compared with prolonged sitting. These effects are linked to physical activity and have been observed outside natural environments.

Nature can therefore create a setting that supports several mutually reinforcing habits. Differences found in some studies between a nature walk and an urban walk suggest that the setting itself may also matter, even though researchers cannot always precisely separate the influence of the scenery, noise, light, or personal preferences.

At Lucis, we consider this approach essential: bringing together the environment, sleep, movement, symptoms, and biological test results. Looking at how these factors interact helps us understand how a person feels and recovers.

The impact of water

Aquatic environments are also being studied. The term “blue spaces” includes coastlines, rivers, and lakes.

In a study involving 59 adults, repeated 20-minute walks by the sea improved immediate mood and well-being more than walks in an urban environment or rest in a control setting. However, cardiovascular responses after the walks did not differ significantly between the environments.

These findings broaden the possibilities. Contact with nature can take different forms, depending on where we live and what we enjoy.

How much time should we spend outdoors?

Two reference points often appear in the research: around 20 minutes per outing and two hours per week. They come from different studies, looking at measures such as salivary cortisol or self-reported health and well-being. They offer guidance for building a habit, rather than a duration everyone needs to follow.

In practice, 20 minutes is a simple starting point. If you have ten minutes, start with ten. The aim is to find a realistic place for these moments so you can repeat them.

Making room for nature in your week

Start by identifying a place near your home or workplace, then attach the outing to an existing habit: a walk after lunch, a detour on your usual route, or a break between periods of focused work. You can also move something you already planned outdoors, such as meeting someone close to you or reading a few pages.

If you are looking for a mental break, keep part of this time free from messages and audio content. Let your attention settle on the sounds, movement, and light around you. You can walk at an easy pace, sit for a few minutes, or alternate between the two.

For one week, try three or four outings of 15 to 20 minutes and simply notice how you feel when you return: your level of tension, how much space your thoughts occupy, and how ready you feel for the rest of the day. This approach mainly helps you discover the conditions that suit you and that you will want to return to.

To better understand what influences your energy and recovery, the Lucis health assessment puts your biological test results into context alongside your symptoms, lifestyle habits, and goals. Our doctors interpret your results to help you identify your priorities and build a personalized action plan.

Scientific references

1. Berman MG, Jonides J, Kaplan S. (2008). The cognitive benefits of interacting with nature. Psychological Science.

2. Bratman GN et al. (2015). Nature experience reduces rumination and subgenual prefrontal cortex activation. PNAS.

3. Burns AC et al. (2021). Time spent in outdoor light is associated with mood, sleep, and circadian rhythm-related outcomes. Journal of Affective Disorders.

4. Dunstan DW et al. (2012). Breaking up prolonged sitting reduces postprandial glucose and insulin responses. Diabetes Care.

5. Hunter MR, Gillespie BW, Chen SY-P. (2019). Urban nature experiences reduce stress in the context of daily life based on salivary biomarkers. Frontiers in Psychology.

6. Ohly H et al. (2016). Attention Restoration Theory: A systematic review of the attention restoration potential of exposure to natural environments. Journal of Toxicology and Environmental Health, Part B.

7. Park BJ et al. (2010). The physiological effects of Shinrin-yoku: Evidence from field experiments in 24 forests across Japan. Environmental Health and Preventive Medicine.

8. Sudimac S, Sale V, Kühn S. (2022). How nature nurtures: Amygdala activity decreases as the result of a one-hour walk in nature. Molecular Psychiatry.

9. Twohig-Bennett C, Jones A. (2018). The health benefits of the great outdoors. Environmental Research.

10. Vert C et al. (2020). Physical and mental health effects of repeated short walks in a blue space environment. Environmental Research.

11. White MP et al. (2019). Spending at least 120 minutes a week in nature is associated with good health and wellbeing. Scientific Reports.

12. Wright KP Jr et al. (2013). Entrainment of the human circadian clock to the natural light-dark cycle. Current Biology.

This content is provided for informational and educational purposes. It does not replace a medical consultation, diagnosis, or treatment. The information presented should be adapted to your individual circumstances with the guidance of a healthcare professional.