Di Domenico Stefano I, Rodrigo Achala H, Ayaz Hasan, Fournier Marc A, Ruocco Anthony C
Department of Psychology, University of Toronto Scarborough, Toronto, Canada.
Department of Psychology, University of Toronto Scarborough, Toronto, Canada.
Neuroimage. 2015 Apr 1;109:307-17. doi: 10.1016/j.neuroimage.2015.01.039. Epub 2015 Jan 24.
Research on the neural efficiency hypothesis of intelligence (NEH) has revealed that the brains of more intelligent individuals consume less energy when performing easy cognitive tasks but more energy when engaged in difficult mental operations. However, previous studies testing the NEH have relied on cognitive tasks that closely resemble psychometric tests of intelligence, potentially confounding efficiency during intelligence-test performance with neural efficiency per se. The present study sought to provide a novel test of the NEH by examining patterns of prefrontal activity while participants completed an experimental paradigm that is qualitatively distinct from the contents of psychometric tests of intelligence. Specifically, participants completed a personal decision-making task (e.g., which occupation would you prefer, dancer or chemist?) in which they made a series of forced choices according to their subjective preferences. The degree of decisional conflict (i.e., choice difficulty) between the available response options was manipulated on the basis of participants' unique preference ratings for the target stimuli, which were obtained prior to scanning. Evoked oxygenation of the prefrontal cortex was measured using 16-channel continuous-wave functional near-infrared spectroscopy. Consistent with the NEH, intelligence predicted decreased activation of the right inferior frontal gyrus (IFG) during low-conflict situations and increased activation of the right-IFG during high-conflict situations. This pattern of right-IFG activity among more intelligent individuals was complemented by faster reaction times in high-conflict situations. These results provide new support for the NEH and suggest that the neural efficiency of more intelligent individuals generalizes to the performance of cognitive tasks that are distinct from intelligence tests.
对智力的神经效率假说（NEH）的研究表明，更聪明的人的大脑在执行简单认知任务时消耗的能量较少，但在进行困难的心理操作时消耗的能量更多。然而，之前测试NEH的研究依赖于与智力心理测量测试非常相似的认知任务，这可能会将智力测试表现中的效率与神经效率本身混淆。本研究旨在通过检查前额叶活动模式来为NEH提供一种新的测试，同时参与者完成一种实验范式，该范式在质量上与智力心理测量测试的内容不同。具体而言，参与者完成了一项个人决策任务（例如，你更喜欢哪种职业——舞者还是化学家？），在该任务中，他们根据自己的主观偏好做出一系列强制选择。根据参与者在扫描前获得的对目标刺激的独特偏好评级，对可用反应选项之间的决策冲突程度（即选择难度）进行了操纵。使用16通道连续波功能近红外光谱测量前额叶皮层的诱发氧合。与NEH一致，智力预测在低冲突情况下右下额叶回（IFG）的激活减少，而在高冲突情况下右IFG的激活增加。在高冲突情况下，反应速度更快补充了更聪明个体中右IFG的这种活动模式。这些结果为NEH提供了新的支持，并表明更聪明个体的神经效率可以推广到与智力测试不同的认知任务表现中。
