Keilp J G, Herrera J, Stritzke P, Cornblatt B A
Department of Psychiatry, Mount Sinai School of Medicine and Elmhurst Hospital Center, NY 11373, USA.
Psychiatry Res. 1997 Mar 14;74(1):35-45. doi: 10.1016/s0925-4927(96)02881-8.
The numbers and shapes subtasks of the CPT-IP are difficulty-matched measures of independent aspects of attentional skill that have been used to differentiate the impairments of schizophrenics and major depressives. Previous studies suggest that they tap into lateralized aspects of attentional performance. To investigate this hypothesis, seven subjects free of psychiatric illness were presented with these CPT-IP subtasks during a SPECT procedure. Subtasks--4-digit number strings and nonsense shapes--were administered on successive weeks, in counterbalanced order, simultaneous with administration of 10 mCi 99mTc HMPAO. Scanning took place after 10 min of test performance. Quantitative data were extracted from each scan via a semi-automated region of interest (ROI) analysis which defined eight cortical and four subcortical ROI on each of five transverse slices. Data for each ROI were normalized and compared between task conditions. Results indicate that the two tasks produce different patterns of functioning within two general areas of the brain. First, during Numbers task performance, left-sided activity was increased on multiple transverse slices in an anterior subcortical region that incorporated the anterior cingulate, frontal white matter, and much of the basal ganglia. Left-sided activity was also increased in a posterior subcortical region including the left side of the thalamus. Lateralization of function, defined as relative activity on the left and right sides, changed within these regions across tasks, but primarily as a result of the contribution of increased or decreased activity on the left side alone. Second, relative perfusion to occipital regions, bilaterally, was more extensive during the Shapes task. These results suggest that subtle alterations in stimulus parameters can affect activation patterns in regions that are critically associated with task performance. They also suggest that the Numbers task may provide more robust activation of anterior attention systems, that may better discriminate the functioning of these systems in normal and psychopathological groups.
连续性能测试-注意力集中部分（CPT-IP）中的数字和形状子任务是注意力技能独立方面的难度匹配测量指标，已被用于区分精神分裂症患者和重度抑郁症患者的损伤情况。先前的研究表明，它们涉及注意力表现的偏侧化方面。为了研究这一假设，在单光子发射计算机断层扫描（SPECT）过程中，让7名无精神疾病的受试者完成这些CPT-IP子任务。子任务——4位数字串和无意义形状——在连续几周内以平衡顺序进行，同时注射10毫居里的99mTc六甲基丙二胺肟（HMPAO）。在测试进行10分钟后进行扫描。通过半自动感兴趣区域（ROI）分析从每次扫描中提取定量数据，该分析在五个横向切片的每一个上定义了八个皮质和四个皮质下ROI。对每个ROI的数据进行归一化处理，并在不同任务条件之间进行比较。结果表明，这两项任务在大脑的两个一般区域内产生不同的功能模式。首先，在数字任务执行期间，多个横向切片上左侧活动在前皮质下区域增加，该区域包括前扣带回、额叶白质和大部分基底神经节。左侧丘脑所在的后皮质下区域的左侧活动也增加。功能偏侧化定义为左右两侧的相对活动，在这些区域内随着任务的变化而改变，但主要是由于仅左侧活动增加或减少的影响。其次，在形状任务期间，双侧枕叶区域的相对灌注更为广泛。这些结果表明，刺激参数的细微变化会影响与任务表现密切相关区域的激活模式。它们还表明，数字任务可能会更有力地激活前部注意力系统，这可能更好地区分正常组和精神病理组中这些系统的功能。
