Impaired mnemonic pattern separation associated with PTSD symptoms paradoxically improves with regular cannabis use
Jacob Ross, Bruna Cuccurazzu, Dylan Delmar, Christian Cortez, Giovanni Castillo, Dean T. Acheson, Dewleen G. Baker, Victoria B Risbrough, Daniel M. Stout
npj Mental Health Research April 24, 2025 DOI: 10.1038/s44184-025-00126-w (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Cross-sectional study Longitudinal Peer reviewed |
|---|---|
| Sample size | 111 |
| Population | Individuals with a range of PTSD symptoms with and without regular cannabis use |
| Topics | Cannabis PTSD |
| Keywords | Mnemonic Cognition Separation statistics Posttraumatic stress Clinical psychology Cognitive psychology |
| Citations | 1 |
| Key findings | Regular cannabis use was associated with greater pattern separation in individuals with high PTSD symptoms but reduced pattern separation in those with low PTSD symptoms. |
Abstract
Posttraumatic stress disorder (PTSD) is associated with poor hippocampal function and disrupted pattern recognition. Cannabis use is highly prevalent in individuals with PTSD, yet the impact on these cognitive functions is poorly understood. Participants (n = 111) with a range of PTSD symptoms with and without regular cannabis use completed the mnemonic similarity task. We hypothesized that regular use would be associated with alterations in pattern separation ability in individuals with PTSD symptoms. High PTSD symptoms were associated with reduced pattern separation performance in minimal users. Regular users with high PTSD symptoms showed greater pattern separation, but reduced pattern separation with low PTSD symptoms. These results suggest that regular cannabis use may disrupt pattern separation and similar hippocampal-dependent processes, while it may improve pattern separation in individuals with high PTSD symptoms. These cross-sectional results require longitudinal follow-up studies to evaluate the causal effects of regular cannabis use on cognitive function in PTSD.
Comparable studies
Other cross-sectional and survey studies on PTSD, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Assessing the quality of publicly available videos on MDMA‐assisted psychotherapy for PTSD Videos on YouTube about MDMA-assisted psychotherapy for PTSD | 2022 | Cross-sectional study | n = 100 |
| Perceptions of psychedelic-assisted therapy among Black Americans. Black and White American adults | 2023 | Cross-sectional survey | n = 294 |
| Coping motives mediate the relationship between PTSD and MDMA use in adolescents with substance use disorders German adolescent SUD patients aged 13–18 years at an outpatient clinic | 2022 | Cross-sectional study | n = 111 |
| Risk factors of sleep paralysis in a population of Polish students. Polish university students under 35 | 2022 | Cross-sectional survey | n = 2,553 |
| Expert opinions on implementation of MDMA-assisted therapy in Europe: critical appraisal towards training, clinical practice, and regulation. Researchers and clinicians involved in MDMA-AT clinical trials and contributors to the... | 2024 | Survey | n = 68 |
Citations in the library
Cites 16
- The short-term impact of 3 smoked cannabis preparations versus placebo on PTSD symptoms: A randomized cross-over clinical trial PLoS One March 17, 2021
- The Relationship Between Cannabis, Cognition, and Schizophrenia: It’s Complicated Current Topics in Behavioral Neurosciences 2022
- Effects of the Acute and Chronic Administration of Cannabidiol on Cognition in Humans and Animals: A Systematic Review. Cannabis and Cannabinoid Research December 2023
- The Long-Term, Prospective, Therapeutic Impact of Cannabis on Post-Traumatic Stress Disorder. Cannabis and Cannabinoid Research April 2022
- An Observational, Longitudinal Study of Cognition in Medical Cannabis Patients over the Course of 12 Months of Treatment: Preliminary Results Journal of the International Neuropsychological Society July 1, 2021
and 11 more in the library