Klingberg T, Roland P E
Department of Neuroscience, Karolinska Institute, Stockholm, Sweden.
Brain Res Cogn Brain Res. 1997 Jul;6(1):1-8. doi: 10.1016/s0926-6410(97)00010-4.
Interference between two concurrent tasks can be measured as an increased reaction time during simultaneous performance compared to when each task is performed alone. We tested the hypothesis that two tasks interfere because they require activation of overlapping areas of the cerebral cortex. With positron emission tomography we measured cortical activation as fields with significant increase in regional cerebral blood flow during single task performance of an auditory and a visual go/no-go task and an auditory and a visual short-term memory (STM) task. In a separate experiment we measured the degree of interference between the two go/no-go tasks and between the two STM tasks during dual task performance. Both the two go/no-go tasks and the two STM tasks activated overlapping parts of the cortex and interfered significantly during dual task performance. The two STM tasks had a larger volume of overlap and also significantly larger increase in reaction time during dual task performance, compared to the go/no-go tasks. The results thus indicate that two concurrent tasks interfere, with a resulting increase in reaction time, if they require activation of overlapping parts of the cortex.
与每个任务单独执行时相比，两个并发任务之间的干扰可以通过同时执行期间反应时间的增加来衡量。我们检验了这样一个假设，即两个任务产生干扰是因为它们需要激活大脑皮层的重叠区域。通过正电子发射断层扫描，我们在执行听觉和视觉的“是/否”任务以及听觉和视觉短期记忆（STM）任务的单任务过程中，将皮质激活测量为局部脑血流量显著增加的区域。在另一个实验中，我们测量了双任务执行期间两个“是/否”任务之间以及两个STM任务之间的干扰程度。两个“是/否”任务和两个STM任务都激活了皮层的重叠部分，并且在双任务执行期间有显著干扰。与“是/否”任务相比，两个STM任务的重叠区域更大，并且在双任务执行期间反应时间的增加也显著更大。因此，结果表明，如果两个并发任务需要激活皮层的重叠部分，它们就会产生干扰，从而导致反应时间增加。
