Effects of Brief Nature Exposure on Brain Functioning and Stress Reactivity

National Institutes of Health (NIH)20 enrolled

Overview

This study is focused on understanding the impact of time spent in nature (relative to an urban control) on stress, neural, and cardiac functioning in people experiencing high levels of stress, depression, and anxiety.

Associations between urbanization and mental illness have long been recognized, but the mechanistic pathways underlying this association are not well understood and likely multifactorial. Reduced contact with nature may contribute to the increased psychopathology observed in urban environments. Theories implicating attention restoration and stress reduction functions via cognitive control and reward brain networks have been proposed to explain how natural environments may decrease stress and promote mental health, particularly in individuals with high-stress loads who are at-risk for developing mental illness. However, most research examining nature's effects on mental health have been observational in design, leaving open questions about nature's effects on neural functioning. Well-controlled studies of brain responses to natural environments will inform stakeholders about potential cognitive and health benefits of nature, as well as guide development of clinical applications like parks prescriptions and nature-based behavioral interventions for individuals who may benefit. This team science grant will enable pilot data collection and a novel collaboration combining faculty expertise in pediatric nature-basedinterventions, clinical neuroscience of reward and motivation, electrophysiological biomarkers of psychiatric vulnerability and integrative healthcare. Further, our team will tap the policy and stewardship expertise of parks system leadership. This project's goal is to conduct a pilot clinical neuroscience study to establish a novel academic-community collaboration and support a larger project proposal to examine neurophysiological mechanisms underlying nature-based clinical interventions to improve mental health in individuals experiencing stress-based symptoms.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Stress (Psychology)

Interventions

Nature vs. Urban walksOTHER

We will evaluate the impact of spending time in nature vs. an urban control on EEG-based measures of reward and attention and resting heart rate variability

Eligibility

Sex: ALLMin age: 18 YearsMax age: 25 Years

Medical Language ↔ Plain English

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

Locations (1)

University of San Francisco California OR San Francisco VA Medical Center

San Francisco, California, United States

RECRUITING

Outcomes

Primary Outcomes

Brain functioning

EEG (neural) measures of attention and reward processing ; resting EEG (including frequency-based analyses of canonical frequency bands, e.g., gamma, beta, alpha, delta, theta) and event-related potential measures (reflecting attention, e.g, P300 and reward/affective processing, e.g., reward positivity, late positive potential).

Time frame: ~1 hour after walking condition

Heart Rate Variability

This measure reflect the variation in heart beat rate, over time. Specifically we will measure heart rate during the EEG recordings and calculate the RMSSD (Root Mean Square of Successive Differences) of heartbeat R-R intervals.

Time frame: ~ 1 hour after walking manipulaation

Data from ClinicalTrials.gov

This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.