Markowitsch H J, Tulving E
University of Bielefeld, Germany.
Proc Natl Acad Sci U S A. 1994 Oct 25;91(22):10507-11. doi: 10.1073/pnas.91.22.10507.
Positron-emission tomography (PET) studies of regional cerebral blood flow have provided evidence relevant to localization of cognitive functions. The critical loci identified in these studies are typically described in terms of macroanatomically labeled cortical and subcortical regions. We report the results of a meta-analysis of localization of changes in blood flow, based on nearly 1000 cerebral cortical peaks of activity obtained from groups of subjects in 30 PET studies. The results showed that, on average, 47% of these peaks were localized within the fundus regions of cortical sulci. This is an unexpectedly high proportion because fundal regions compose < 8% of the cortical mantle. Further analysis suggested a coarse correlation between the extent of fundal activation observed in different studies and the estimated cognitive complexity of the tasks used in the studies. These findings are potentially interesting because (i) the preponderance of fundal activation has implications for the interpretation of the PET data, (ii) they suggest that cortical sulcal and fundal regions may play a distinctive role in higher cognitive processing, or (iii) both of the above.
正电子发射断层扫描（PET）对局部脑血流量的研究为认知功能定位提供了相关证据。这些研究中确定的关键位点通常根据宏观解剖学标记的皮质和皮质下区域来描述。我们报告了一项基于30项PET研究中受试者群体获得的近1000个大脑皮质活动峰值的血流变化定位的荟萃分析结果。结果表明，平均而言，这些峰值中有47%位于皮质沟的底部区域。这一比例出乎意料地高，因为底部区域占皮质层的比例不到8%。进一步分析表明，不同研究中观察到的底部激活程度与研究中使用的任务的估计认知复杂性之间存在粗略的相关性。这些发现可能很有趣，因为（i）底部激活占优势对PET数据的解释有影响，（ii）它们表明皮质沟和底部区域可能在高级认知处理中发挥独特作用，或者（iii）以上两者皆有。
