Brief nature walks to see effects on brain function and stress reactivity.

YONDER Study (Effects of Brief Nature Exposure on Brain Functioning and Stress Reactivity)

Observational San Francisco Veterans Affairs Medical Center · NCT07508800

We will try short nature walks (compared with urban walks) to see if they lower stress and change brain and heart activity in people with high perceived stress, depression, or anxiety.

Quick facts

Study typeObservational
Enrollment20 (estimated)
Ages18 Years to 25 Years
SexAll
SponsorSan Francisco Veterans Affairs Medical Center Federal
Locations1 site (San Francisco, California)
Trial IDNCT07508800 on ClinicalTrials.gov

What this trial studies

Adults with high perceived stress will be assigned to brief outdoor nature or urban walks and undergo EEG and cardiac measurements before and after the walk. EEG tasks will probe attention and reward-processing networks while cardiac measures capture stress reactivity. Participants may include those with current or past depression or anxiety if they meet the stress cutoff and have stable medications. The goal is to link brief nature exposure with neural and physiological markers that could guide nature-based recommendations and clinical programs.

Who should consider this trial

Good fit: Ideal candidates are adults scoring above 27 on the PSS-10 with normal or corrected vision and stable psychotropic medication regimens of more than one month, including those with current or past depression or anxiety.

Not a fit: People with severe mental illnesses (bipolar or schizophrenia spectrum), current or past substance use disorders, major neurological disorders, significant uncontrolled medical conditions, or estimated IQ below 75 are unlikely to qualify or benefit from this protocol.

Why it matters

Potential benefit: If successful, this work could support simple, low-cost nature-based recommendations to help reduce stress and improve brain and heart functioning for people with high stress.

How similar studies have performed: Prior observational research has repeatedly linked nature exposure to reduced stress and improved mood, but well-controlled studies measuring EEG and cardiac responses are limited, so this approach builds on promising but not definitive evidence.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Meets cut-off for high level of perceived stress on PSS-10 during screening (\>27 total score); Current or past depressive and anxiety disorders, if present on SCID-5 assessment, will be ncluded due to their high prevalence and overlap with perceived stress
* Normal, or corrected to normal, vision (due to the visual nature of the EEG tasks)
* If on psychotropic medication, stable regime for \> 1 month

Exclusion Criteria:

* Major medical conditions with CNS sequelae (e.g., seizure disorders, multiple sclerosis, significant, uncontrolled cardiovascular pathology) Past or present neurological problems (including seizures and head trauma resulting in neurological or cognitive sequelae)
* IQ estimate \<75 on the Test of Premorbid Functioning
* Current or past history of severe mental illness (e.g., bipolar schizophrenia spectrum disorder, or current or past history of substance use disorders

Where this trial is running

San Francisco, California

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Stressnatureeegreward processingattention functioningstress
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.