“…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.…”