MRI STUDIES OF BRAIN FUNCTION AND METABOLISM

CBDB的功能MRI组包括： 具有神经病学、精神病学、 物理学、生物学和MRI技术。这个群体追求各种各样的 涉及大脑功能研究的研究议程， 正常人和神经精神疾病患者的代谢 特别是精神分裂症，阿尔茨海默型老年痴呆， 运动障碍和脑血管疾病。最大的份额 在过去的一年里， 认知激活的全脑研究 在神经精神任务和脑代谢物成像期间（N 乙酰天冬氨酸、胆碱和肌酸）的磁共振成像 在正常个体中， 神经精神障碍和精神分裂症的动物模型。 从这些研究中出现了几个有趣的发现：1） 在假定的关键节点中存在容量约束， 工作记忆网络，2）患者 精神分裂症会更快地达到这种能力，但在他们的能力范围内， 约束显示正常的生理关系，3）氯胺酮，a 非竞争性N-甲基-D-天冬氨酸受体拮抗剂， 导致正常人的工作记忆回路发生变化 类似于精神分裂症患者中所见的，即达到 工作记忆容量比当受试者 安慰剂，4）苯丙胺引起认知特异性信号 增强，5）同侧皮质运动区被招募 在优势和非优势的手运动，但这 在不太熟悉和自动化程度较低的任务中， 不管是哪只手或哪只半球。6)患者 精神分裂症患者及其兄弟姐妹的 海马NAA与对照组比较。的这种图案 神经化学异常可能代表大脑的“表型” 与精神分裂症有关。7)低相对NAA 在背外侧前额叶皮层的浓度预测更高的 脑梗死患者基底节D-2结合电位的变化 精神分裂症，8）精神分裂症患者，NAA措施， 背外侧前额叶皮层与 整个工作记忆网络，包括前额叶，顶叶， 颞叶和扣带皮层9）前额叶神经元的完整性 皮质与工作记忆相关 用IL 2治疗的HIV阳性成人的损伤。的研究 未来几年将继续在临床测试领域， 优化成像协议，改善空间和 时间分辨率，认知激活的大脑研究， 神经精神任务与药物操作，和 绘制脑功能和代谢的家庭成员， 有患精神分裂症等神经精神疾病的风险， 阿尔茨海默病等。可以想象，遗传风险标志物， 可能用于联系研究。

The functional MRI group of CBDB consists of multidisciplinary specialists with expertise in neurology, psychiatry, physics, biology and MRI techniques. This group pursues a variety of research agendas involving study of brain function and metabolism in normals and patients with neuropsychiatric disorders particularly schizophrenia, senile dementia of the Alzheimer's type, movement disorders and cerebrovascular disorders. The lion's share of the effort of this group over the last year has been in the implementation of whole brain studies of cognitive activation during neuropsychiatric tasks and imaging of brain metabolites (N acetyl aspartate, choline and creatine) using magnetic resonance specroscopic imaging (MRSI) in normal individuals, patients with neuropsychiatric disorders and in animal models of schizophrenia. Several interesting findings have emerged from these studies: 1) there is a capacity constraint in the key nodes of the putative network underlying working memory, 2) patients with schizophrenia reach this capacity sooner, but within their capacity constraints show normal physiological relationships, 3) ketamine, a non- competitive N-methyl-D-Aspartate receptor antagonist, induces changes in the working memory circuitry of normal subjects similar to those seen in patients with schizophrenia i.e. reaching the working memory capacity sooner than when the subjects were on placebo, 4) dextroamphetamine causes cognitively specific signal augmentation, 5) ipsilateral cortical motor areas are recruited during both dominant and non- dominant hand movements, but this appears to be more so in less familiar and less automatic tasks regardless of the hand or hemisphere involved. 6) patients with schizophrenia and their siblings had significant reductions in hippocampal NAA as compared with controls. Such a pattern of neurochemical abnormality may represent a brain 'phenotype' associated with schizophrenia. 7) lower relative NAA concentrations in the dorsolateral prefrontal cortex predict a higher D-2 binding potential in the basal ganglia of patients with schizophrenia, 8) in patients with schizophrenia, NAA measures in dorsolateral prefrontal cortex strongly correlate with activation of the entire working memory network, including prefrontal, parietal, temporal, and cingulate cortices 9) neuronal integrity of prefrontal cortex as measured by NAA, correlates with working memory impairment in HIV positive adults treated with IL2. Studies in the upcoming years will continue in the realm of clinical testing and optimization of imaging protocols with improved spatial and temporal resolution, of brain studies of cognitive activation during neuropsychiatric tasks with pharmacological manipulations, and mapping brain function and metabolism in family members who are at risk for neuropsychiatric illnesses such as schizophrenia, Alzheimer's disease, etc. It is conceivable that a genetic risk marker, possibly of use in linkage studies, could be identified.