DEVELOPMENT OF COGNITIVE ACTIVATION TASKS FOR FUNCTIONAL NEUROIMAGING

在过去的一年里，我们开发了各种认知任务， PET和MRI中的功能性神经成像。 1. 我们开发了一个空间延迟反应任务， 在短时间内保持非语言信息。 PET激活是 在一个物理分布的神经网络中， 皮质、枕叶皮质和辅助运动皮质。 2. 我们已经开发了一种语言流畅性范例， 语音材料的流畅性（即，受试者被要求说， 尽可能多的以给定字母开头的单词， 语义流畅性（受试者被要求陈述尽可能多的语义 尽可能地选择一个类别）。 我们发现PET激活 左侧布罗卡区和韦尼克区的语音流畅 半球 我们发现语义流畅性的激活程度相对较高 在上级颞叶。 这两种流畅性模式也要求 前额叶和扣带回的活动，可能与提取有关。 3. 我们开发了连续工作记忆任务，其中数字 信息必须在短时间内保持， 干扰 在这项任务中，受试者必须对一个数字做出反应， 以前曾出现过，但不再出现在屏幕上， 给出了一组连续的数字。 在这项任务中，有“一个 “一背两背”的条件，以操纵难度。 4. 一个双任务干扰范式，以评估 难度水平的显著增加是否会产生更大的激活 或者在给定区域中较少激活。 初步 结果表明小脑可能参与双重任务， 也许，与“分时”功能有关。 5. 在视频游戏的背景下的快速手指敲击过程将 用于激活多巴胺能神经元， 在基底神经节区域中产生由于多巴胺能 神经元活动

Over the past year, we have developed a variety of cognitive tasks for functional neuroimaging in PET and MRI. 1. We have developed a spatial delayed response task that involves maintaining non-verbal information over short delays. PET activation was noted in a physically distributed neural network that included prefrontal cortex, occipital cortex, and supplementary motor cortex. 2. We have developed a verbal fluency paradigm which involves paced fluency for phonologic materials (i.e., the subject is asked to say as many words beginning with a given letter as possible in comparison to semantic fluency (the subject is requested to state as many semantic exemplars of a given category as possible). We found PET activation for phonologic fluency in Broca's area and Wernicke's area in the left hemisphere. We found relatively greater activation for semantic fluency in the superior temporal lobe. Both fluency paradigms also demanded prefrontal and cingulate activity, perhaps in relationship to retrieval. 3. We have developed continuous working memory task in which numeric information must be maintained over short delays in the face of interference. In this task, the subject must respond to a number that had been previously present, but was no longer present on the screen as a continuous set of numbers is presented. In this task, there are "one back and two back" conditions in order to manipulate difficulty. 4. A dual task interference paradigm was developed in order to assess whether marked increases in difficulty level produce greater activation in a given region or less activation in a given region. Preliminary results indicated that the cerebellum may participate in dual tasks, perhaps, in relationship to a "time-sharing" function. 5. A rapid finger tapping procedure in the context of a video game will be used in order to activate dopaminergic neurons in the hope of producing activation in basal ganglia regions due to dopaminergic neuronal activity.