bioRxiv : the preprint server for biology
January 24, 2026
Kwang-Hyun Hur, Lisa D Nickerson, Jack Bergman et al.
THC, the psychoactive compound in cannabis, selectively amplifies behavioral and brain responses to cues that predict rewards, without affecting responses to neutral cues or baseline reward consumption. In squirrel monkeys, a low dose of THC (3 μg/kg) increased conditioned approach behavior toward a visual stimulus associated with food delivery. Functional MRI showed that THC enhanced activity in reward-related brain regions—anterior cingulate cortex, striatum, hippocampus, and substantia nigra-ventral tegmental area (SN-VTA)—while leaving visual and motor cortices unaffected. Resting-state connectivity analyses revealed that THC strengthened communication within mesocorticolimbic networks, with the SN-VTA acting as a central hub. These findings indicate that THC boosts incentive salience and motivational drive toward reward-associated stimuli through selective modulation of this circuitry.
BMC Psychology
January 21, 2026
Christina Chwyl, Angelica Spata, Will Lucas et al.
Psychological context, or 'set,' is more strongly linked to the outcomes of psychedelic experiences than the specific substance used, suggesting a 'mindset-over-molecule' pattern. The findings indicate that the mental state and expectations of the user play a more influential role than the chemical properties of the drug alone.
The Cochrane database of systematic reviews
January 19, 2026
Gülay Ateş, Patrick Welsch, Petra Klose et al.
5 citations
Chronic pain with a nerve-damage component affects 6–10% of the population, and current drugs help only a minority. Cannabis is widely promoted as a treatment. This updated Cochrane review analyzed 21 randomized, double-blind trials with 2,187 adults suffering from chronic neuropathic pain. For THC-dominant cannabis, there was no clear evidence of at least 50% pain relief or meaningful improvement on a global scale, though nervous system side effects (e.g., dizziness, drowsiness) were increased. Balanced THC/CBD medicines may slightly increase global improvement ratings and pain relief of at least 30%, but these effects were not clinically meaningful and also raised the risk of side effects.
JAMA Network Open
January 2, 2026
Moshe Berchansky, A Eden Evins, Bryn Evohr et al.
1 citation
A brain-imaging technique called resting-state functional near-infrared spectroscopy (fNIRS) detected THC-induced impairment more accurately and with far fewer false positives than standard behavioral field sobriety tests (FSTs). In a double-blind, randomized crossover trial, 183 regular cannabis users (average age 25, half female) received either a single oral dose of synthetic THC or a placebo. fNIRS scans of the prefrontal cortex, taken at rest and during a working-memory task, were used to train machine-learning models to identify clinically determined intoxication. The fNIRS classifier achieved 90% accuracy and a 5% false-positive rate, compared with 69% accuracy and a 34% false-positive rate for FSTs. The findings suggest that resting-state fNIRS may provide a more reliable, objective method for detecting cannabis-related driving impairment.
Journal of Cannabis Research
January 2, 2026
Sunitha Vemuri, Samantha M. Ayoub, Arpi Minassian et al.
Delta-9-tetrahydrocannabinol (THC), the main psychoactive component of cannabis, reduced pain sensitivity, body temperature, and movement in HIV-1 transgenic rats and their controls, with some differences between males and females. A higher dose (3 mg/kg) also temporarily lowered motivation to work for a reward, but this effect disappeared after 16 days of daily treatment. HIV-1 transgenic rats showed lower motivation than one control strain (Fischer344) but not another (wildtype littermates), highlighting the importance of choosing appropriate control groups in research.
Clinical Neurophysiology Practice
January 1, 2026
William T Creel, Colleen A Brenner, Richard E Hartman
Frequent cannabis use is associated with reduced neural signal complexity in the prefrontal cortex, as measured by multiscale entropy (MSE) of resting-state EEG. In 57 adults—non-users, low-frequency users (≤1x/week), and frequent users (≥2x/week)—MSE increased with coarser temporal scales in all groups, but the slope was significantly flatter in frequent users. From medium to very-coarse scales, their prefrontal entropy slope was 0.12 to 0.16 bits lower than non-users. Across all participants, the prefrontal cortex showed lower MSE than parietal, occipital, and temporal lobes, with larger differences at coarser scales. MSE detects cannabis-related reductions in prefrontal signal complexity at longer temporal scales.
Contemporary Clinical Trials
January 1, 2026
Christine A Rabinak, Paul E Kilgore, Mark A Lumley et al.
Prolonged exposure (PE) therapy is effective for PTSD, but dropout and partial response remain problems. This trial tests whether synthetic THC (dronabinol) can improve PE outcomes. Adults with PTSD are randomly assigned to receive 7.5 mg THC or placebo before PE sessions 3 through 6, when extinction learning occurs. The study measures PTSD symptom severity, brain activation during fear extinction, and physiological responses. If THC enhances extinction learning, this FDA-approved drug could be quickly added to PE therapy to boost its effectiveness.
Frontiers in sports and active living
January 1, 2026
Brandon A Ally, Paul A Mentele, Scott A Wylie
Chronic THC use slows game-speed cognition in NCAA football players. Eighteen Division I athletes who tested positive for THC completed the S2 Cognition Football Battery at baseline and after 12 months of verified abstinence. At baseline, users showed approximately 20% slower reaction speed compared to their own post-abstinence values, consistent with an 80-100 ms delay in decision execution. Significant improvements after abstinence occurred in Decision Complexity, Distraction Control, Impulse Control, Multiple-Object Tracking, Speeded Target Detection, Improvisation, and the overall S2 Composite. Effects persisted after controlling for reaction speed, indicating domain-specific recovery beyond global speeding. The findings suggest that chronic THC use imposes a measurable performance cost that is partially reversible with abstinence.
Psychopharmakotherapie
January 1, 2026
Antonia Bendau, Felix Betzler, Twyla Michnevich et al.
1 citation
Party drugs are a diverse group of legal and illegal psychoactive substances used in social settings like clubs and festivals to alter mood, perception, and social interaction. Alcohol and cannabis are most common, followed by amphetamine, MDMA, cocaine, and ketamine. These drugs act through various pharmacological mechanisms: alcohol affects GABAergic, glutamatergic, and dopaminergic systems; cannabis acts on the endocannabinoid system; stimulants increase monoaminergic neurotransmitters; MDMA has a strong serotonergic component; ketamine produces dissociative effects via glutamatergic mechanisms; and psychedelics alter sensory processing through serotonergic modulation. Polydrug use is frequent. Acute risks include cardiovascular strain, hyperthermia, and anxiety, while long-term consequences can involve cognitive impairments, dependence, and social complications.
Global advances in integrative medicine and health
January 1, 2026
Haley D M Schuman, Raèf Mina, Sofia Barkova et al.
Healthcare providers in Canada hold cautious to supportive views on psychedelic-assisted therapy, with ketamine pragmatically accepted for its rapid effects but raising concerns about commercialization, psilocybin seen as promising for end-of-life existential distress yet viewed with mixed feelings, and MDMA considered useful for trauma but constrained by neurotoxicity worries and regulatory barriers. An ethical tension emerged between access to medical assistance in dying and restrictions on psychedelic-assisted therapy in end-of-life care, highlighting policy inconsistencies. Providers emphasized the need for substance-specific guidelines, interdisciplinary education, and evidence-informed regulatory reform.
The Journal of law, medicine & ethics : a journal of the American Society of Law, Medicine & Ethics
January 1, 2026
Holly Fernandez Lynch, Xinping Hu, Alison Bateman-House
2 citations
Psychedelic medicines show potential for treating serious mental health conditions, creating demand before FDA approval. Policymakers should balance evidence, patient safety, and speed by increasing research support, avoiding barriers to research, improving FDA's pre-approval access, and preventing politically driven approvals.
Substance Abuse and Rehabilitation
January 1, 2026
Ethan Murphy, Chao Suo, Govinda Poudel et al.
Acute intoxication with delta-9-tetrahydrocannabinol (THC) is consistently associated with greater brain activity in fronto-striatal pathways. Regular cannabis users, compared to non-users, show lower hippocampal volume, reduced white matter microstructure in the superior longitudinal fasciculus, and altered fronto-striatal activity and connectivity during cue-reactivity tasks and at rest. Emerging evidence from Positron Emission Tomography studies indicates lower N-acetyl aspartate, reduced glucose metabolism in the frontal cortex, and lower density of cannabinoid receptors in fronto-striatal pathways, which may reverse with abstinence. Longitudinal multimodal neuroimaging studies are needed to determine whether these brain differences precede or follow cannabis use and whether they dissipate with abstinence.