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Completed Not applicable Interventional Accepts healthy volunteers

The Combined Effect of Chronic Cannabis Use and Subconcussive Head Impacts on Brain Health

ClinicalTrials.gov ID: NCT04641832

Public ClinicalTrials.gov record NCT04641832. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 5, 2026, 7:11 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

The Effect of Chronic Cannabis Use on Neural Response to Acute Subconcussive Head Impacts

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

The purpose of this pilot study is to better understand the effects of chronic cannabis (THC) use on the neural responses to subconcussive head impacts, as a form of repetitive soccer headings. The study is designed to identify the physiological changes of cannabis using cohort (THC) and compare it to a nonusing cohort in order to see if the responses to 20 controlled bouts of soccer headings are exacerbated by the chronic cannabis use, diminished to less of a response, or unchanged, through an array of neurologic measures, including cognitive function, ocolar-motor function, autonomic function, and blood biomarkers. The hypothesis is that repetitive subconcussive head impacts will impair cognitive function in worse memory, attention span, and visual and verbal problem solving; this impairment will be greater in the chronic cannabis use groups than non-using group. The blood and salivary biomarkers neurofilament light (NFL) and glial fibrillary acidic protein (GFAP) will be measured in plasma, with the hypothesis that repetitive subconcussive head impacts will significantly increase plasma NFL and GFAP level at 24 hours-post heading and decrease by 72 hours-post heading, while remaining undetectable at 2 hours-post heading; the chronic cannabis use groups will see more severe effects on ocular-motor function than the non-using group. The study aims to determine the differences in acute effects of subconcussive head impacts on eye movement, attention, and language function between chronic cannabis use subjects and non-using subjects by evaluating ocular-motor function with near point of convergence and King-Devick tests. The hypothesis is that repetitive subconcussive head impacts will significantly increase impairments of eye movements, attention, and language function, as well as near point of convergence; the chronic cannabis use groups will see more severe effects on hampered ocular-motor function than the non-using group. Lastly, there is a cold pressor test to assess autonomic nerve function, with the hypothesis that repetitive subconcussive head impacts will decrease autonomic nerve function in chronic cannabis use patients to a greater degree than non-using subjects.

Study identification

NCT ID
NCT04641832
Recruitment status
Completed
Study type
Interventional
Phase
Not applicable
Lead sponsor
Indiana University
Other
Enrollment
70 participants

Conditions and interventions

Interventions

Other

Eligibility (public fields only)

Age range
18 Years to 26 Years
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 29, 2020
Primary completion
Sep 30, 2021
Completion
Nov 30, 2021
Last update posted
Mar 1, 2023

2020 – 2021

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Indiana University School of Public Health Bloomington Indiana 47405

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT04641832, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Mar 1, 2023 · Synced Sep 5, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT04641832 live on ClinicalTrials.gov.

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