ABSTRACT
The purpose of this research was to develop a cognitive factors research laboratory that could measure the subtle, carry-over effects of various drugs such as marijuana and other factors such as aging on psychomotor performance found in complex human-machine interaction. The three experiments reviewed are a chronology of our efforts. The findings reported indicate that marijuana impairs complex psychomotor performance for up to 24 hours after smoking a low to moderate social dose. The results also indicate that marijuana and other factors such as task difficulty and aging act to cumulatively impair performance. These findings suggest that there may be conditions under which real world complex human-machine performance is significantly impaired with out the subjective awareness of the marijuana user.
