CHRONIC MARIJUANA USE--BRAIN AND COGNITION

描述：(申请人摘要) 这项提案的目标是检查长期使用大麻对 人类大脑结构、脑功能和认知的最新技术 将神经成像技术与认知评估相结合的方法。 如果一些大麻使用者出现长期的大脑功能障碍， 潜在的社会成本在医疗成本的增加和减少中 生产率可能会很高。大麻是使用最广泛的非法药物。 在美国，在经历了十多年的普遍下降后，其 在过去的3-4年里，年轻人的受欢迎程度显著上升，促使 人们再次担心其可能对健康造成的后果。 药物滥用和神经成像研究人员将联手提出 重病患者认知功能障碍的研究 大麻使用者和研究大麻对大脑结构和 应用磁共振成像检测局部脑血流量(RCBF) 正电子发射断层扫描(PET)。认知激活 在PET成像期间进行的测试将根据我们之前的 宠物工作和长期使用大麻的研究，并将强调测试 记忆和注意力。我们假设长期吸食大麻的人会表现出 这些认知功能的损害和脑区rCBF的减少 我们之前发现在执行这些测试期间处于活动状态 在正常对照组中。这些类型的更广泛的测试将是 在单独的疗程中进行，不涉及神经成像。大麻 用户和非用户在智能功能上将在 开始使用药物，使用标准化测试的分数记录 可供爱荷华州几乎所有地区的受教育儿童使用。类似 将对受试者进行适合成年人的测试，以评估他们的 当前的能力。 之前只有几项研究考察了慢性前列腺癌的影响 通过神经成像技术使用大麻，除了一项外，所有人都进行了 几年前。神经成像技术检测脑内细微变化的能力 近年来，大脑的结构和功能有了很大的改善。不是 之前对长期吸食大麻的研究评估了大脑的变化 与特定认知活动相关的功能。最新版本 关于大麻对认知的慢性影响的研究一直在进行 方法薄弱，除了我们之前的研究外，没有人观察到 与对照组相比，吸食大麻者的认知障碍 疾病前的智力能力。因此，在完成后，拟议的 研究将对现有的关于以下方面的知识进行重要补充 长期吸食大麻对人脑结构、脑功能的影响 和认知力。

DESCRIPTION: (Applicant's Abstract) The goal of this proposal is to examine effects of chronic marijuana use on human brain structure, brain function, and cognition using state-of-the-art methods for combining neuroimaging techniques with cognitive assessments. If some marijuana users develop long term cerebral dysfunction, the potential costs to society in increased health care costs and decreased productivity could be high. Marijuana is the most widely used illicit drug in the U.S.A. Following well over a decade of generally declining use, its popularity has increased markedly among youth in the last 3-4 yr, prompting renewed concerns about its possible health consequences. Drug abuse and neuroimaging researchers will join forces in the proposed research to replicate our earlier findings of cognitive impairments in heavy marijuana users and study marijuana's effects on brain structure and regional cerebral blood flow (rCBF) using magnetic resonance imaging and positron emission tomography (PET), respectively. Cognitive activation tests administered during PET imaging will be selected based on our previous PET work and research on chronic marijuana use, and will emphasize tests of memory and attention. We hypothesize that chronic marijuana users will show impairments in these cognitive functions and reduced rCBF in brain regions that we have previously found to be active during performance of these tests in normal controls. More extensive tests of these types will be administered in a separate session not involving neuroimaging. Marijuana users and non-users will be matched on intellectual function before the onset of drug use, using records of scores on standardized tests that are available for children educated in virtually all parts of Iowa. Similar tests suitable for adults will be administered to subjects to assess their current capabilities. Only a handful of previous studies have examined effects of chronic marijuana use with neuroimaging techniques, and all but one were conducted years ago. Abilities of neuroimaging techniques to detect subtle changes in brain structure and function have improved enormously in recent years. No previous studies of chronic marijuana use have assessed changes in brain function associated with specific cognitive activities. Most previous studies of marijuana's chronic effects on cognition have been methodologically weak, and none except our own previous study observed cognitive impairments in marijuana users relative to controls matched on premorbid intellectual abilities. Thus, when completed, the proposed research will make important additions to existing knowledge concerning effects of chronic marijuana use on human brain structure, brain function, and cognition.