Please use this link to access this publication: https://www.sciencedirect.com/science/article/abs/pii/009130579090028G?via%3Dihub Abstract Three experienced marijuana smokers participated in four 2-day experimental sessions in which they smoked either 0, 1, or 2 marijuana cigarettes containing 2.57% Δ9-tetrahydrocannabinol (THC) at two different times on the first day. A battery of physiological, subjective, and performance measures was repeated throughout day 1 to assess acute effects and on day 2 to measure any residual effects of marijuana. Blood samples were also repeatedly collected to examine the relationship between plasma levels and pharmacological effects of THC. Acutely, marijuana increased heart rate and subjective ratings of drug effects and slightly impaired performance on...