Neurochemical alterations in adolescent chronic marijuana smokers: a proton MRS study.
Andrew P Prescot, Allison E Locatelli, Perry F Renshaw, Deborah A Yurgelun-Todd
Neuroimage July 1, 2011 DOI: 10.1016/j.neuroimage.2011.02.044 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Cross-sectional observational study Peer reviewed |
|---|---|
| Sample size | 34 |
| Population | Adolescent marijuana users and healthy non-using controls |
| Measures | proton magnetic resonance spectroscopy (1H MRS) |
| Topics | Cannabis |
| Key findings | Adolescent marijuana users had significantly lower anterior cingulate cortex levels of glutamate (-15%), N-acetyl aspartate (-13%), total creatine (-10%), and myo-inositol (-10%) compared with non-using controls. The authors interpret these reductions as possibly reflecting altered glutamatergic neurotransmission and neuronal integrity, and changes in energetic status and glial metabolism. |
Abstract
Converging evidence from neuroimaging and neuropsychological studies indicates that heavy marijuana use is associated with cingulate dysfunction. However, there has been limited human data documenting in vivo biochemical brain changes after chronic marijuana exposure. Previous proton magnetic resonance spectroscopy studies have demonstrated reduced basal ganglia glutamate and dorsolateral prefrontal cortex N-acetyl aspartate levels in adult chronic marijuana users. Similar studies have not been reported in adolescent populations. The present study used proton magnetic resonance spectroscopy to determine whether reductions in glutamate, N-acetyl aspartate and/or other proton metabolite concentrations would be found in the anterior cingulate cortex (ACC) of adolescent marijuana users compared with non-using controls. Adolescent marijuana users (N=17; average age 17.8 years) and similarly aged healthy control subjects (N=17; average age 16.2 years) were scanned using a Siemens 3T Trio MRI system. Proton magnetic resonance spectroscopy data were acquired from a 22.5 mL voxel positioned bilaterally within the ACC. Spectra were fitted using commercial software and all metabolite integrals were normalized to the scaled unsuppressed water integral. Analysis of variance and analysis of covariance were performed to compare between-group metabolite levels. The marijuana-using cohort showed statistically significant reductions in anterior cingulate glutamate (-15%, p<0.01), N-acetyl aspartate (-13%, p=0.02), total creatine (-10%, p<0.01) and myo-inositol (-10%, p=0.03). Within-voxel tissue-type segmentation did not reveal any significant differences in gray/white matter or cerebrospinal fluid content between the two groups. The reduced glutamate and N-acetyl aspartate levels in the adolescent marijuana-using cohort are consistent with precedent human (1)H MRS data, and likely reflect an alteration of anterior cingulate glutamatergic neurotransmission and neuronal integrity within these individuals. The reduced total creatine and myo-inositol levels observed in these subjects might infer altered ACC energetic status and glial metabolism, respectively. These results expand on previous functional MRI data reporting altered cingulate function in individuals with marijuana-abuse.
Comparable studies
Other cross-sectional and survey studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Cannabis use before age 15 and subsequent executive functioning 104 chronic cannabis users (49 early-onset before age 15, 55 late-onset after age 15)... | 2011 | Observational cross-sectional study | n = 148 |
| Patterns of simultaneous polysubstance use in drug using university students Drug-using university students | 2006 | Cross-sectional survey | n = 149 |
| Persisting Reductions in Cannabis, Opioid, and Stimulant Misuse After Naturalistic Psychedelic Use: An Online Survey Online survey respondents | 2020 | Cross-sectional survey | |
| User perceptions of the benefits and harms of hallucinogenic drug use: A web-based questionnaire study Users of hallucinogenic drugs who completed a web-based questionnaire | 2010 | Cross-sectional survey | n = 600 |
| Illicit Use of LSD or Psilocybin, but not MDMA or Nonpsychedelic Drugs, is Associated with Mystical Experiences in a Dose-Dependent Manner Adults recruited from the MAPS website and newsletter, most reporting use of various... | 2012 | Cross-sectional survey | n = 337 |
Citations in the library
Cited by 14
- The neuropsychopharmacology of cannabis: A review of human imaging studies Pharmacology & Therapeutics October 20, 2018
- Reduced responsiveness of the reward system is associated with tolerance to cannabis impairment in chronic users Addiction Biology December 22, 2019
- Evidence That Cannabis Exposure, Abuse, and Dependence Are Related to Glutamate Metabolism and Glial Function in the Anterior Cingulate Cortex: A 1H-Magnetic Resonance Spectroscopy Study Frontiers in Psychiatry August 20, 2020
- Cannabis Use and Neuroadaptation: A Call for Δ9-Tetrahydrocannabinol Challenge Studies Frontiers in Psychiatry April 14, 2022
- Impact of cannabis use on brain metabolism using 31P and 1H magnetic resonance spectroscopy Neuroradiology September 22, 2023
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Cites 6
- Chronic cannabis users show altered neurophysiological functioning on Stroop task conflict resolution. Psychopharmacology December 2010
- Altered affective response in marijuana smokers: an FMRI study. Drug and Alcohol Dependence November 1, 2009
- Dorsolateral prefrontal cortex N-acetylaspartate/total creatine (NAA/tCr) loss in male recreational cannabis users. Biological Psychiatry June 1, 2007
- Neuroimaging of marijuana smokers during inhibitory processing: a pilot investigation. Brain research. Cognitive brain research April 2005
- Cannabis as a risk factor for psychosis: systematic review Journal of Psychopharmacology March 1, 2005
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