Objective. This study examined the relationship between neural activity and executive function (EF) by near-infrared spectroscopy (NIRS). In addition, an oral reading span test (RST) was used to explore this association. Methods. Fifteen adults participated in the study. We used the RST and simple reading as the two tasks. Results. The RST score and cortical hemodynamic response in the left inferior frontal gyrus were significantly correlated. Conclusion. Based on the oral RST performance assessment and NIRS examination, the present findings suggest a relationship between EF and cortical activation. 1. Introduction As an executive function (EF), working memory refers to the brain system that stores and manipulates information over brief periods and represents a key process for cognitive functions such as planning, reasoning, and problem solving [1]. The reading span test (RST) was developed and implemented to behaviorally measure individual differences in verbal working memory capacity employed by processing and storage functions during reading [2]. The RST is a dual-task paradigm in which participants are required to read a sentence and simultaneously remember target words. This span correlates with three reading comprehension measures, including the verbal scholastic aptitude test (SAT) and tests involving fact retrieval and pronominal references. These results contrast with those of traditional digit span and word span measures that do not correlate with comprehension [2]. The reader must also store the text theme, representation of the situation to which it refers, major propositions from preceding sentences, and a running, multilevel representation of the sentence that is currently being read. Thus, language comprehension is an excellent example of a task that demands extensive storage of partial and final products during complex information processing [2]. Recent neuroimaging studies have attempted to explore the neural basis of working memory systems based on Baddeley’s theory [3]. It has been proposed that two types of working memory processes, which are executive control processes, are observed in distinct cortical structures located in the prefrontal cortex (PFC) and modality-specific buffers located in more posterior regions [4–6]. Activation of the dorsolateral PFC is observed when two types of tasks are performed together [7], such as during a task performed with a self-monitoring system [8] or during a task requiring executive control [9]. In this view, resource allocation during the span task would be controlled by the central executive
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