BACKGROUND: Cognitive correlates of long-term cannabis use have been elusive. We tested the hypothesis that long-term cannabis use is associated with deficits in short term memory, working memory, and attention in a literate, westernized culture (Costa Rica) in which the effects of cannabis use can be isolated. METHODS: Two cohorts of long-term cannabis users and nonusers were studied. Within each cohort, users and nonusers were comparable in age and socioeconomic status. Polydrug users and users who tested positive for the use of cannabis at the time of cognitive assessment after a 72-hour abstention period were excluded. The older cohort (whose age was approximately 45 years) had consumed cannabis for an average of 34 years, and comprised 17 users and 30 nonusers, who had been recruited in San José, Costa Rica, and had been observed since 1973. The younger cohort (whose age was approximately 28 years) had consumed cannabis for an average of 8 years, and comprised 37 users and 49 nonusers. Short-term memory, working memory, and attentional skills were measured in each subject. RESULTS: Older long-term users performed worse than older nonusers on 2 short-term memory tests involving learning lists of words. In addition, older long-term users performed worse than older nonusers on selective and divided attention tasks associated with working memory. No notable differences were apparent between younger users and nonusers. CONCLUSION: Long-term cannabis use was associated with disruption of short-term memory, working memory, and attentional skills in older long-term cannabis users.
BACKGROUND: Cognitive correlates of long-term cannabis use have been elusive. We tested the hypothesis that long-term cannabis use is associated with deficits in short term memory, working memory, and attention in a literate, westernized culture (Costa Rica) in which the effects of cannabis use can be isolated. METHODS: Two cohorts of long-term cannabis users and nonusers were studied. Within each cohort, users and nonusers were comparable in age and socioeconomic status. Polydrug users and users who tested positive for the use of cannabis at the time of cognitive assessment after a 72-hour abstention period were excluded. The older cohort (whose age was approximately 45 years) had consumed cannabis for an average of 34 years, and comprised 17 users and 30 nonusers, who had been recruited in San José, Costa Rica, and had been observed since 1973. The younger cohort (whose age was approximately 28 years) had consumed cannabis for an average of 8 years, and comprised 37 users and 49 nonusers. Short-term memory, working memory, and attentional skills were measured in each subject. RESULTS: Older long-term users performed worse than older nonusers on 2 short-term memory tests involving learning lists of words. In addition, older long-term users performed worse than older nonusers on selective and divided attention tasks associated with working memory. No notable differences were apparent between younger users and nonusers. CONCLUSION: Long-term cannabis use was associated with disruption of short-term memory, working memory, and attentional skills in older long-term cannabis users.
Authors: Gen Kanayama; Jadwiga Rogowska; Harrison G Pope; Staci A Gruber; Deborah A Yurgelun-Todd Journal: Psychopharmacology (Berl) Date: 2004-06-16 Impact factor: 4.530
Authors: Jiansong Xu; Adrianna Mendrek; Mark S Cohen; John Monterosso; Paul Rodriguez; Sara L Simon; Arthur Brody; Murray Jarvik; Catherine P Domier; Richard Olmstead; Monique Ernst; Edythe D London Journal: Biol Psychiatry Date: 2005-07-15 Impact factor: 13.382
Authors: Gerry Jager; Rene S Kahn; Wim Van Den Brink; Jan M Van Ree; Nick F Ramsey Journal: Psychopharmacology (Berl) Date: 2006-03-07 Impact factor: 4.530
Authors: Madeline H Meier; Avshalom Caspi; Antony Ambler; HonaLee Harrington; Renate Houts; Richard S E Keefe; Kay McDonald; Aimee Ward; Richie Poulton; Terrie E Moffitt Journal: Proc Natl Acad Sci U S A Date: 2012-08-27 Impact factor: 11.205