Abstract

In order to grasp the difference between “the cat on the mat” and “the mat on the cat,” understanding the words and the grammar is not enough. Rather it is essential to visualize the cat and the mat together to appreciate their relations. This type of imagination, which involves juxtaposition of mental objects is conducted by the prefrontal cortex and is therefore called Prefrontal Synthesis (PFS). PFS acquisition has a strong experience-dependent critical period putting children with language delay in danger of never acquiring PFS and, consequently, not mastering complex language comprehension. In typical children, the timeline of PFS acquisition correlates with vocabulary expansion. Conversely, atypically developing children may learn many words but never acquire PFS. In these individuals, intelligence tests based on vocabulary assessment may miss the profound deficit in PFS. Accordingly, we developed a test specific for PFS — Linguistic Evaluation of Prefrontal Synthesis or LEPS — and administered it to 50 neurotypical children, age 4.1 ± 1.3 years and to 23 individuals with impairments, age 16.4 ± 3.0 years. All neurotypical children older than 4 years received the LEPS score 7/10 or greater indicating good PFS ability. Among individuals with impairments only 39% received the LEPS score 7/10 or greater. LEPS was 90% correct in predicting high-functioning vs. low-functioning class assignment in individuals with impairments.

摘要

为了掌握“the cat on the mat”和“the mat on the cat”之间的区别，仅仅理解单词和语法是不够的。相反，必须将猫和垫子一起想象以欣赏它们的关系。这种涉及心理对象并置的想象是由前额叶皮层进行的，因此被称为前额叶综合（PFS）。PFS 习得具有强烈的经验依赖性关键期，使语言迟缓的儿童面临永远不会获得 PFS 的危险，因此无法掌握复杂的语言理解。在典型的儿童中，PFS 习得的时间线与词汇扩展相关。相反，非典型发育的儿童可能会学习很多单词，但永远不会获得 PFS。在这些人中，基于词汇评估的智力测试可能会错过 PFS 的严重缺陷。因此，我们开发了一种专门针对 PFS 的测试——前额叶合成或 LEPS 的语言评估——并将其应用于 50 名年龄为 4.1 ± 1.3 岁的神经型儿童和 23 名年龄为 16.4 ± 3.0 岁的有障碍的个体。所有 4 岁以上的神经型儿童均获得 7/10 或更高的 LEPS 评分，表明 PFS 能力良好。在有损伤的个体中，只有 39% 的 LEPS 得分为 7/10 或更高。LEPS 在预测有缺陷的个体的高功能与低功能类别分配方面的正确率为 90%。3 岁和 23 名有障碍的人，年龄 16.4 ± 3.0 岁。所有 4 岁以上的神经型儿童均获得 7/10 或更高的 LEPS 评分，表明 PFS 能力良好。在有损伤的个体中，只有 39% 的 LEPS 得分为 7/10 或更高。LEPS 在预测有缺陷的个体的高功能与低功能类别分配方面的正确率为 90%。3 岁和 23 名有障碍的人，年龄 16.4 ± 3.0 岁。所有 4 岁以上的神经型儿童均获得 7/10 或更高的 LEPS 评分，表明 PFS 能力良好。在有损伤的个体中，只有 39% 的 LEPS 得分为 7/10 或更高。LEPS 在预测有缺陷的个体的高功能与低功能类别分配方面的正确率为 90%。