“…In relation to reckless behavior, a study of 18-year-old Swedish draftees found that low-MAO males were higher in SSS scores than high-MAO males, and the low-MAO males were also more likely to report reckless behavior such as drug use and criminality (von Knorring, Oreland, & Winbald, 1983). Low MAO levels are also characteristic of alcoholics (Major & Murphy, 1978) and chronic marijuana users (Stillman et al, 1978). Since MAO is negatively correlated with sensation seeking and sensation seeking is negatively correlated with age, one might reasonably expect to find that MAO levels increase with age; one study (Robinson, Davis, Nies, Ravaris, & Sylvester, 1971) bears this out, although another (Murphy, Wright, Buchsbaum, Nichols, Costa, & Wyatt, 1976) reports no age differences in MAO levels.…”