A comparative structural and functional cerebral MRI study of first episode schizophrenia and long-term cannabis use.

首发精神分裂症和长期大麻使用的比较结构和功能性脑 MRI 研究。

• 批准号: nhmrc : 300734
• 负责人: A/Pr Patrick Johnston
• 金额: $ 24.88万
• 依托单位国家: 澳大利亚
• 项目类别: NHMRC Project Grants
• 财政年份: 2004
• 资助国家: 澳大利亚
• 起止时间: 2004-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/comparative-structural-functional-cannabis-use/76766
• 关键词: comparative; structural; functional; cerebral; MRI

Cannabis is used for its subjective effects that include euphoria, depersonalisation, somnolence, and altered perceptions of temporal contingency.It is a controlled substance yet one quarter of Australian adolescents and seven percent of adults use cannabis regularly. Chronic use of cannibis can impair frontal brain functioning, affecting the capacities for attention, working memory and concentration.These neurocognitive deficits bear striking similarities to those associated with the negative symptom cluster of schizophrenia,which is related to frontal brain dysfunction. The proposed study will be the first of it's kind to apply sophisticated neuroimaging techniques to investigate how long-term adolescent cannabis use effects the structure and function of the brain and to make comparative analyses with the brain changes associated with first episode schizophrenia. We predict that structural brain abnormalities that are consistent in localisation, if not in degree, will be detected in long-term cannabis using and first episode schizophreniaparticipants and that there will be even more profound abnormalities in the first episode schizophrenia cannabis users. We will use the Tower of London (TOL) task to activate certain areas associated with executive functioning (for instance attention, memory, and strategic planning). Here, we expect lower intensity activation of the prefrontal cortex during TOL performance both in the cannabis and first episode schizophrenia groups and that the activation will be lowest of all for the cannabis using first episode schizophrenia group. The methodology to be applied in this study offers a unique opportunity to enhance our understanding of the structural and functional markers of first episode schizophrenia and cannabis use in the neural substrate.

大麻被用于其主观效应，包括欣快感、人格解体、嗜睡和对时间偶然性的感知改变。它是一种受管制的物质，但四分之一的澳大利亚青少年和7%的成年人经常使用大麻。长期使用大麻会损害大脑额叶功能，影响注意力、工作记忆和注意力。这些神经认知缺陷与精神分裂症的阴性症状群有惊人的相似之处，后者与额叶脑功能障碍有关。这项拟议中的研究将首次应用复杂的神经成像技术来研究青少年长期使用大麻对大脑结构和功能的影响，并与首发精神分裂症相关的大脑变化进行比较分析。我们预测，在长期使用大麻和首次发作的精神分裂症患者中，如果不是在程度上，也会发现与局部一致的大脑结构异常，而在首次发作的精神分裂症大麻使用者中，甚至会有更严重的异常。我们将使用伦敦塔（TOL）任务来激活与执行功能相关的某些区域（例如注意力、记忆力和战略规划）。在这里，我们预计在TOL表现中，大麻和首发精神分裂症组的前额叶皮层的激活强度较低，而在首发精神分裂症组中，使用大麻的激活强度最低。本研究中应用的方法提供了一个独特的机会，以增强我们对首发精神分裂症和大麻使用在神经基质中的结构和功能标记的理解。