A synthetic cannabinoid agonist, nabilone, reduces the tactile funneling illusion—a phenomenon where two simultaneous touches on the skin are perceived as a single sensation in between. In a randomized, double-blind, placebo-controlled crossover trial with 32 healthy participants, nabilone decreased the illusion in a delay-dependent manner, particularly when stimuli were delivered simultaneously (0 ms delay). It also reduced errors in localizing touches in a distance-dependent way. The drug increased ratings on two of five psychometric scales but did not change overall scores. Associations between overall psychometric scores and the illusion under the strongest condition depended on the drug. Unlike dexamphetamine, which widens stimulus binding windows, nabilone narrows them, reducing illusory perception.
A single low oral dose of the synthetic cannabinoid nabilone (1-2 mg) impaired both verbal and spatial working memory in healthy adults, with a stronger effect in people who used cannabis less frequently. Spatial working memory was more affected than verbal working memory. The drug did not significantly change psychosis-like experiences (schizotypy scores). However, higher schizotypy scores were linked to worse working memory under placebo, and more frequent cannabis use was associated with better overall working memory across drug conditions, suggesting tolerance to the memory-impairing effects of cannabinoids.
A single-blind, placebo-controlled crossover study tested whether a synthetic THC analogue, Nabilone (1-2 mg), alters the sense of agency and body ownership in 32 healthy volunteers, comparing effects to those previously seen in schizophrenia. The study found that Nabilone had multimodal and bidirectional effects on the projected hand illusion, widening the spatio-temporal binding window in some participants and narrowing it in others, depending on spatial and temporal conditions. Evidence supported a unitary spatio-temporal binding window rather than separate spatial and temporal windows. No significant associations were found between agency and embodiment measures, and a large proportion of participants did not experience the illusion.