Nature as Medicine for the Healing Brain: Utilization of a Nature-based Exposure Intervention for Decreasing Concussion Recovery Timeline and Symptom Load

Overview

The overall goal of this research is to provide pilot data that informs and drives a larger scale research project, incorporating multiple contemporary measurement modalities, to understand the utility and pathological mechanisms by which exposure to nature-based settings may aid in recovery time and symptom relief of individuals suffering from concussion, and decrease their risk of developing Persistent Post-Concussion Syndrome (PPCS). We hypothesize that successful adherence to a nature-based exposure therapy intervention program will decrease recovery time and severity of symptom trajectory of concussion, as measured through multimodal assessments of brain structural and functional integrity.

Detailed description

This study will use a resting state combined electrophysiological-imaging measure of brain region activation, a blood-based measure of neuroinflammatory protein circulation, and a brief but comprehensive neuropsychological functional assessment to identify recovery status of the brain pre- and post-intervention. Measures will be taken at two pre-determined time intervals following concussion for each participant (1-3 days, 28-30 days) and frame the start and end point of a 4-week nature-based exposure therapy intervention program. The self-administered nature-based exposure therapy intervention will consist of 4 weeks of 120 minutes per week (spread over 3-7 days) of nature-based exposure coupled with a guided environmental awareness prompt list per week (Harries et al., 2025; Leão et al., 2025; White et al., 2019).

The primary aim of this study will be to assess the utility of a nature-based exposure therapy intervention in decreasing symptom severity and timeline of concussion. The intervention will include a multi-week program during which patients will participate in a specified duration of emersion in "nature-based environments". This intervention will inform a low-risk, holistic method for concussion management and may decrease risk of PPCS onset. A multimodal measurement battery will assess structural, functional, and behavioral concussion recovery factors as they relate to the nature-based intervention. Trends in recovery measures will be recorded at pre- and post-intervention, as well as throughout the intervention time period to assess both the feasibility/adherence and efficacy of nature-based exposure on recovery from concussion.

Interventions

• Behavioral Nature-based Guided Awareness Group
  Participants in the nature-based guided awareness group will be instructed to perform their intervention prompt in a one of the safe, accessible natural settings provided on the study's Nature-Based Location Guide, 3-7 times per week, for a total duration of 120 minutes per week.
• Behavioral Standard Guided Awareness Group
  Participants in the standard guided awareness group will be instructed to perform the prompt in a quiet, controlled indoor environment, 3-7 times per week, for a total duration of 120 minutes per week.

Primary outcome measures

• Concussion Symptoms Scales [Time frame: Daily, for the duration of the 28 day study]

Secondary outcome measures (6)

• Stroop Task [Time frame: On day 1 (visit 1) and day 28 (visit 2) of the 28 day study.]
• Oral Digit Symbol Modalities Task [Time frame: On day 1 (visit 1) and day 28 (visit 2) of the 28 day study.]
• Beck's Depression Inventory [Time frame: On day 1 (visit 1) and day 28 (visit 2) of the 28 day study.]
• Hamilton Anxiety Scale [Time frame: On day 1 (visit 1) and day 28 (visit 2) of the 28 day study.]
• Neuroinflammatory Biomarker Concentration [Time frame: On day 1 (visit 1) and day 28 (visit 2) of the 28 day study.]
• EEG-fNRIS [Time frame: On day 1 (visit 1) and day 28 (visit 2) of the 28 day study.]

Eligibility criteria

Inclusion criteria

• Require that any participant is 14-35 years old
• Required that any participant under 18 years old can be accompanied by a parent or legal guardian for the duration of the study
• Required that participants be English speakers
• Required that persons be able to provide consent for themselves
• Required that the participant must have suffered a clinically diagnoses concussion 5 days or less prior to the first study visit
• Concussion must have been diagnosed by a licensed clinical medicine professional.
• No additional professional treatment modalities outside of normal clinical concussion recovery recommendations may have been received prior to study participation. These include participation in a separate concussion rehabilitation study, cognitive behavioral therapies, vestibule-ocular therapies (balance), in-patient physical therapy, consumption of stimulant medication, and chiropractic manipulation.
• Injury must have been diagnosed as a concussion or mild-traumatic brain injury. Participant must not have been diagnosed with of severe traumatic brain injury, hematoma, fractured skull or facial bones, or comatose.

Exclusion criteria

• Exclude persons under 14 years old or over 35 years old
• Exclude persons taking anti-inflammatory drugs (both prescription and OTC), or those who will have taken them within 24 hours prior to Visit 1
• Exclude smokers and former smokers, as defined by CDC. (Anyone who smokes daily or who has smoked at least 100 cigarettes in their lifetime)
• Those with presence of an active infection (including a dental infection)
• Exclude persons who have migraines
• Exclude persons taking mood stabilizer medications
• Exclude persons who have consumed alcohol within 48 hours prior to study participation, participants will be asked this by one of the study members through the exclusion criteria screening form when they first contact the study
• Exclude persons who are pregnant.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

United States · 1 center

• Recreation Building — University Park

Publications

• Leao ER, Savieto RM, Borba GB, da Silva Victor E, Bomfim SB, Hingst-Zaher E, Lima LM, Longo LGR, de Oliveira LB, Noguchi DT, Oliveira LPG, Moredo RF, Santos CO, Menini A, Bass LM, Patricio KP, Catissi G, Rosa JM, Soldado EBR, Bertini F, de Barros CG, Kiriyama EJ. Efficacy of a multicomponent nature-based intervention on well-being and environmental engagement: A randomized clinical trial. Environ PMID 39874898
• Leao ER, Hingst-Zaher E, Savieto RM, Patricio KP, de Oliveira LB, Catissi G, Lima LM, Borba GB, Bomfim SB, de Abreu FB. A time with e-Natureza (e-Nature): a model of nature-based health interventions as a complex adaptive system. Front Psychol. 2023 Aug 22;14:1226197. doi: 10.3389/fpsyg.2023.1226197. eCollection 2023. PMID 37674757
• Gay M, Ray W, Johnson B, Teel E, Geronimo A, Slobounov S. Feasibility of EEG Measures in Conjunction With Light Exercise for Return-to-Play Evaluation After Sports-Related Concussion. Dev Neuropsychol. 2015;40(4):248-53. doi: 10.1080/87565641.2015.1014486. PMID 26179490
• Corazon SS, Olsen LJ, Kaereby N, Poulsen DV, Sidenius U, Bekke-Hansen S, Marschner L. Nature-Based Therapeutic Intervention for Individuals with Post-Concussion Symptoms. Behav Sci (Basel). 2024 Jul 12;14(7):594. doi: 10.3390/bs14070594. PMID 39062417

Identifiers

NCT: NCT07642739 · Nature Intervention Concussion

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗