Abstract:
Face identity recognition (FIR) in humans is supported by specialized neural processes whose function is spectacularly impaired when simply turning a face upside-down: the face inversion effect (FIE). While the FIE appears to have a slow developmental course, little is known about the plasticity of the neural processes involved in this effect-and in FIR in general-at adulthood. Here, we investigate whether extensive training (2 weeks, ~16 h) in young human adults discriminating a large set of unfamiliar inverted faces can reduce an implicit neural marker of the FIE for a set of entirely novel faces. In all, 28 adult observers were trained to individuate 30 inverted face identities presented under different depth-rotated views. Following training, we replicate previous behavioral reports of a significant reduction (56% relative accuracy rate) in the behavioral FIE as measured with a challenging four-alternative delayed-match-to-sample task for individual faces across depth-rotated views. Most importantly, using EEG together with a validated frequency tagging approach to isolate a neural index of FIR, we observe the same substantial (56%) reduction in the neural FIE at the expected occipito-temporal channels. The reduction in the neural FIE correlates with the reduction in the behavioral FIE at the individual participant level. Overall, we provide novel evidence suggesting a substantial degree of plasticity in processes that are key for face identity recognition in the adult human brain.
摘要:
人类的面部身份识别(FIR)得到了专门的神经过程的支持,这些过程的功能在简单地将面部上下颠倒时受到了惊人的损害:面部倒置效应(FIE)。虽然FIE似乎发展缓慢,关于这种效应所涉及的神经过程的可塑性,以及在成年后的FIR中,人们知之甚少。这里,我们调查是否进行了广泛的培训(2周,〜16h)在年轻人中,区分大量不熟悉的倒置面孔可以减少一组完全新颖面孔的FIE的隐式神经标记。总之,对28名成年观察者进行了培训,以个性化在不同深度旋转视图下呈现的30个倒置面部身份。培训后,我们复制了以前的行为报告,即行为FIE的显著降低(56%的相对准确率),这是在深度旋转视图中对单个人脸进行具有挑战性的4种替代延迟匹配样本任务所测量的.最重要的是,使用EEG和经过验证的频率标记方法来分离FIR的神经指数,我们观察到预期的枕部-颞部通道的神经FIE也有相同的实质性减少(56%).神经FIE的减少与个体参与者水平的行为FIE的减少相关。总的来说,我们提供了新的证据,表明在成人大脑中面部身份识别的关键过程中具有很大程度的可塑性。