Enduring changes in personality/attitudes , depression , spirituality , anxiety , wellbeing , substance misuse , meditative practice s , and mindfulness were documented .
Mystical experiences , connectedness , emotional breakthrough , and increased neural entropy were related to these long-term changes in psychological functioning .
Finally , with proper screening , preparation , supervision , and integration , limited aversive side effects were noted by study participants .
Research into the basic effects and therapeutic applications of  psychedelic drugs  has grown considerably in recent years .
Yet , pressing questions remain regarding the substances ' lasting effects .
Although individual studies have begun monitoring sustained changes , no study to- date has synthesized this information .
Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance
Rationale Although psilocybin has been used for centuries for religious purpose s , little is known scientifically about its acute and persisting effects . Objectives This double-blind study evaluated the acute and longer-term psychological effects of a high dose of psilocybin relative to a comparison compound administered under comfortable , supportive conditions . Material s and methods The participants were hallucinogen-naïve adults reporting regular participation in religious or spiritual activities . Two or three sessions were conducted at 2-month intervals . Thirty volunteers received orally administered psilocybin ( 30 mg/70 kg ) and methylpheni date hydrochloride ( 40 mg/70 kg ) in counterbalanced order . To obscure the study design , six additional volunteers received methylpheni date in the first two sessions and unblinded psilocybin in a third session . The 8-h sessions were conducted individually . Volunteers were encouraged to close their eyes and direct their attention inward . Study monitors rated volunteers ’ behavior during sessions . Volunteers completed question naires assessing drug effects and mystical experience immediately after and 2 months after sessions . Community observers rated changes in the volunteer ’s attitudes and behavior . Results Psilocybin produced a range of acute perceptual changes , subjective experiences , and labile moods including anxiety .  Psilocybin also increased measures of mystical experience . At 2 months , the volunteers rated the psilocybin experience as having substantial personal meaning and spiritual significance and attributed to the experience sustained positive changes in attitudes and behavior consistent with changes rated by community observers . Conclusions When administered under supportive conditions , psilocybin occasioned experiences similar to spontaneously occurring mystical experiences . The ability to occasion such experiences prospect ively will allow rigorous scientific investigations of their causes and consequences
Enduring changes in personality/attitudes , depression , spirituality , anxiety , wellbeing , substance misuse , meditative practice s , and mindfulness were documented .
Mystical experiences , connectedness , emotional breakthrough , and increased neural entropy were related to these long-term changes in psychological functioning .
Finally , with proper screening , preparation , supervision , and integration , limited aversive side effects were noted by study participants .
Research into the basic effects and therapeutic applications of  psychedelic drugs  has grown considerably in recent years .
Yet , pressing questions remain regarding the substances ' lasting effects .
Although individual studies have begun monitoring sustained changes , no study to- date has synthesized this information .