Abstract:
This fMRI study of 126 youth explored whether the neural mechanisms underlying the N-back task, commonly used to examine executive control over the contents of working memory, are associated with individual differences in academic achievement in reading and math. Moreover, the study explored whether these relationships occur regardless of the nature of the stimulus being manipulated in working memory (letters, numbers, nonsense shapes) or whether these relationships are specific to achievement domain and stimulus type (i.e., letters for reading and numbers for math). The results indicated that higher academic achievement in each of reading and math was associated with greater activation of dorsolateral prefrontal cortex in the N-back task regardless of stimulus type (i.e., did not differ for letters and numbers), suggesting that at least some aspects of the neural mechanisms underlying these academic domains are executive in nature. In addition, regardless of level of academic achievement, prefrontal regions were engaged to a greater degree for letters than numbers than nonsense shapes. In contrast, nonsense shapes yielded greater hippocampal activation than letters and numbers. Potential reasons for this pattern of findings are discussed.
摘要:
这项对126名青年的fMRI研究探讨了N-back任务背后的神经机制,通常用于检查对工作记忆内容的执行控制,与阅读和数学学业成绩的个体差异有关。此外,这项研究探讨了这些关系是否发生,无论在工作记忆中被操纵的刺激的性质如何(字母,数字,无意义形状),或者这些关系是否特定于成就领域和刺激类型(即,用于阅读的字母和用于数学的数字)。结果表明,无论刺激类型如何,阅读和数学方面的较高学业成绩都与N背任务中背外侧前额叶皮层的更大激活有关(即,字母和数字没有差异),这表明这些学术领域的神经机制的至少某些方面在本质上是执行的。此外,无论学术成就水平如何,前额叶区域对字母的参与程度大于数字,而不是无义形状。相比之下,无义形状比字母和数字产生更大的海马激活。讨论了这种发现模式的潜在原因。