COGNITIVE CONSEQUENCES OF LONG-TERM MARIJUANA USE

描述：（申请人摘要） 在长期使用大麻的健康和医疗后果中， 残余神经心理学影响的可能性-例如 注意力、记忆力和其他认知功能-仍然是一个领域， 关心 但这些影响仍然知之甚少，因为 现有研究方法的局限性。 具体来说，许多研究 研究了大麻使用者，他们一生中只接触过少量的 药物，因此，有II型错误的风险-未能检测到 如果一个事实上存在。 在剩下的研究中， 大部分测试用户仅在24-48小时后， 戒断大麻，在许多情况下，戒断期不是 监督。 因此，观察到的任何缺陷可能只是反映了残留物 最近吸食大麻素的大脑，或者， 突然停止吸食大麻的戒断反应。 因此，我们认为， 显然需要进一步研究，以解决是否 长期使用大麻会产生临床上有意义的残留 神经毒性 本申请中提出的研究试图解决方法学问题， 早期调查的问题在几个方面。 一是 调查人员将研究那些吸食大麻至少5000年的人。 （相当于每天吸烟一次，持续13.7年）， 最大限度地减少上述第二类错误的风险。 其次，用户将 在28天内接受一系列神经心理学测试 对大麻和其他毒品的戒断，每天观察 尿液收集。 这项技术将使研究人员能够 区分由于药物残留或 戒断反应和明显的神经毒性造成的长期损害。 研究人员进行的可行性研究表明， 有可能招募大量长期吸食大麻的人 使用者（平均终生吸烟次数= 19，000），年龄30 - 54岁， 性别和一系列种族和社会经济群体，谁将是 愿意参与这项拟议设计的研究。 的电池 神经心理学测试，其中许多已经被用于 在之前一项关于大麻对大学生影响的研究中， 被选择来评估广泛的皮质功能，包括 特别是注意力/执行功能在以前的 对大麻吸食者的研究 额外 研究者自己设计的神经心理学测试和额外的 成瘾研究中心的一系列尿液和血液样本的分析 在巴尔的摩，MD，将提供进一步的数据之间的关系 大麻使用，大麻素水平和各种类型的可能 神经心理学效应 鉴于大麻在当代美国人中的广泛使用， 结果应提供重要的信息，为立法和监管 与这种药物有关的机构。

DESCRIPTION: (Applicant's Abstract) Among the health and medical consequences of long-term marijuana use, the possibility of residual neuropsychological effects - such as impairments of attention, memory and other cognitive functions - remains an area of concern. But these effects are still poorly understood because of the methodological limitations of existing studies. Specifically, many studies have examined marijuana users with only modest total lifetime exposure to the drug, and, thus, are at risk for a type II error - failing to detect an effect if one in fact exists. Of the remaining studies which have examined users with substantial exposure, most tested users after only 24-48 hours of abstinence from marijuana and in many cases the abstinence period was not supervised. Thus, any deficits observed may have simply reflected a residue of recently smoked cannabinoids in the brain, or alternatively, acute withdrawal effects from abrupt discontinuation of marijuana. Therefore, further study is clearly required to resolve the question of whether long-term marijuana use produces clinically meaningful residual neurotoxicity. The study proposed in this application seeks to address the methodological problems of earlier investigations in several ways. First, the investigators will study individuals who have smoked marijuana at least 5000 times (the equivalent of smoking once per day for 13.7 years) in order to minimize the risk of a type II error as described above. Second, users will receive serial neuropsychological tests over the course of a 28-day period of abstinence from marijuana and other drugs, monitored by daily observed urine collections. This technique will allow the investigators to distinguish between temporary impairment due either to a residue of drug or to withdrawal effects, and prolonged impairment due to frank neurotoxicity. A feasibility study, performed by the investigators, has demonstrated that it is possible to recruit substantial numbers of long-term heavy marijuana users (mean lifetime number of episodes of smoking = 19,000), age 30 to 54, of both genders and a range of ethnic and socioeconomic groups, who would be willing to participate in a study of this proposed design. A battery of neuropsychological tests, many of which have already been used by the investigators in a previous study of marijuana effects in college students, has been chosen to assess a wide range of cortical functions, including particularly the attentional/executive functions found impaired in previous studies of marijuana users at this center and others. Additional neuropsychological tests of the investigators' own design and additional analyses of serial urine and blood samples at the Addiction Research Center in Baltimore, MD, will provide further data on the relationship between marijuana use, cannabinoid levels and various types of possible neuropsychological effects. Given the widespread use of marijuana among contemporary Americans, these results should provide important information for legislative and regulatory bodies concerned with this drug.