Brain Development of Adolescent Marijuana Users

青少年大麻使用者的大脑发育

• 批准号: 6953604
• 负责人: ROBERT I BLOCK
• 金额: $ 54.89万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-30 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6953604
• 关键词: adolescence (12-20); behavioral /social science research tag; cerebral cortex; clinical research; cognition; developmental neurobiology; functional ability; hippocampus; human subject; magnetic resonance imaging; marijuana abuse; neurotoxicology; positron emission tomography; prefrontal lobe /cortex

DESCRIPTION (provided by applicant): The proposed research will examine effects of age of first use of marijuana and duration of use on brain function, brain structure, and cognition. Considering that marijuana is the most widely used illicit drug, if chronic use produces brain dysfunction in some marijuana users and this dysfunction is greater in those who begin use earlier during adolescence and use longer, the potential costs to society could be high. Using positron emission tomography and magnetic resonance imaging, we will examine differences of chronic marijuana users from control subjects in baseline regional cerebral blood flow and cognition-related changes in regional cerebral blood flow (in memory, tapping and gambling tests), as well as whole brain blood flow and brain tissue volume and composition. We hypothesize that chronic marijuana users will differ from control subjects and these differences will be more pronounced in marijuana users with earlier ages of first use and longer durations of use. Hypothesized effects of chronic marijuana use on regional cerebral blood flow in posterior cerebellum, prefrontal cortex, and hippocampus are particular foci of the proposed research. If the hypothesized effects occur, they will provide evidence that chronic marijuana use alters brain functioning and that the pronounced brain development that normally occurs during adolescence increases vulnerability to such alterations. Additional, more extensive cognitive tests will be administered in sessions not involving neuroimaging to test the hypothesis that cognitive effects of marijuana use are also more pronounced in individuals with earlier ages of first use and longer durations of use. Groups of subjects will be matched on premorbid intellectual functioning using records of standardized test scores that are available for children educated in virtually all parts of Iowa. No published studies except ours have demonstrated changes in brain function and cognition in chronic marijuana users relative to control subjects matched on premorbid intellectual functioning. When completed, the proposed research will make important additions to knowledge about effects of chronic marijuana use on human brain function, brain structure, and cognition.

描述（由申请人提供）： 拟议的研究将检查大麻首次使用年龄和使用持续时间对脑功能，大脑结构和认知的影响。考虑到大麻是使用最广泛使用的非法药物，如果长期使用在某些大麻使用者中会产生脑功能障碍，并且这种功能障碍在青春期开始使用并使用更长的人使用的人会更大，那么社会的潜在成本可能很高。使用正电子发射断层扫描和磁共振成像，我们将研究基线区域脑血流中控制受试者的慢性大麻使用者的差异，以及区域脑血流（记忆，攻击和赌博测试中）以及全脑血液流量和大脑血流的体积和组成的区域性脑血流中与认知相关的变化。我们假设慢性大麻使用者将与控制对象有所不同，而这些差异将在早期使用和使用时间更长的大麻使用者中更为明显。慢性大麻使用对拟议研究的特定焦点是慢性大麻使用对脑后，前额叶皮层和海马的区域脑血流的影响。 如果发生了假设的影响，他们将提供证据表明慢性大麻使用会改变大脑的功能，并且通常在青春期发生的明显大脑发育会增加这种改变的脆弱性。 在不涉及神经影像学的会议上，还将进行其他更广泛的认知测试，以检验以下假设：使用大麻使用的认知效应在早期使用初期和使用时间更长的人中也更为明显。使用标准化考试成绩的记录，将在爱荷华州的所有部位受过教育的儿童中使用标准化考试成绩的记录，将受试者组匹配。除了我们的研究表明，相对于在病前智力功能匹配的控制受试者的慢性大麻使用者的大脑功能和认知的变化外，没有发表的研究。完成后，拟议的研究将对有关慢性大麻使用对人脑功能，大脑结构和认知影响的影响的知识进行重要的补充。