Bilingual effects on cognitive shifting and prefrontal activations in young children

Abstract

Aims and objectives: Bilingual children constantly experience spontaneous switching between languages in everyday settings, and some researchers suggest that this experience leads to an advantage in task performance during executive function tasks. Neural processing during executive function tasks remains largely unknown, especially in young bilingual children. Methodology: Using functional near-infrared spectroscopy, this study examined whether young children who attended an immersion second-language program demonstrated enhanced cognitive shifting and lateral prefrontal activation. Data and analysis: We recruited children ( N = 24) who attended an international nursery school, and examined whether their performance on cognitive shifting, and whether the oxygenated hemoglobin changes in the prefrontal regions during the task, were correlated with the children’s second-language verbal age and the length of time the children had been speaking the second language. Findings: Results revealed that the verbal age of the second language and the length of time speaking it were significantly correlated with behavioral performances of cognitive shifting tasks. However, they were not correlated with the activations in the lateral prefrontal regions. Originality: We examined the neural correlates of bilingual effects on cognitive shifting and prefrontal activations in young children. Implications: The results suggest that second-language experience may not be directly related to neural processing in the lateral prefrontal cortex, at least in young children.

A Functional Near-Infrared Spectroscopy Examination of the Neural Correlates of Cognitive Shifting in Dimensional Change Card Sort Task

“…The task arrangement in this study has been developed from the HaND paradigm (Lloyd-Fox et al, 2019). It could be named the "habituation-dishabituation paradigm of DCCS task, " which differs from the task arrangement in the previous study (Moriguchi and Lertladaluck, 2020). First, this arrangement asked children to follow three rule orders during the three sessions to control learning effects.…”

An fNIRS examination of executive function in bilingual young children

“…The EEG study by Barac et al (2016) demonstrated that better differentiation of the N2/ P3 waveform was associated with better discriminability of go and no-go trials of bilingual children. The fNIRS study by Moriguchi and Lertladaluck (2019) have demonstrated that the activation in the right lateral prefrontal regions was correlated with successes during the DCCS task. Still, the correlation between activated regions and the bilingual experience was not significant, calling for more extensive research on how bilingualism affects children's neural processing in the PFC.…”

“…Early bilingual experience and its impact on executive function have been a topical issue in bilingual neuroimaging studies (Moriguchi & Lertladaluck, 2019). The experience of shifting between two languages by inhibiting irrelevant information and attending to relevant information may affect the neural functioning during task switching (Buac & Kaushanskaya, 2014).…”

“…Some existing studies have suggested that early bilingual experience can positively affect the development of executive function (EF) (Tran et al, 2019;Weber et al, 2016). However, a recent study examining Japanese preschooler's performance during the Dimensional Change Card Sort (DCCS) task using functional near-infrared spectroscopy (fNIRS) found that early bilingual ability was not significantly correlated with the activation of lateral prefrontal regions (Moriguchi & Lertladaluck, 2019). Due to inconsistency in the literature, this study aimed to replicate the previous study (Moriguchi & Lertladaluck, 2019) and crosscheck this finding by examining the activation of prefrontal cortex in Chinese-English bilinguals during the DCCS task using fNIRS.…”

Effect of Picture-Book Reading With Additive Audio on Bilingual Preschoolers’ Prefrontal Activation: A Naturalistic Functional Near-Infrared Spectroscopy Study

“…For example, Arredondo et al (2017) found that early bilingualism could yield significant changes to the functional organization of schoolchildren's PFC for non-verbal attentional control, especially within the left hemisphere, associated with normative language processing and bilingual language switching. While Moriguchi and Lertladaluck (2019) failed to find an association between L2 immersion time and brain function for cognitive shifting among 3-to 5-year-old bilinguals, suggesting insufficient L2 exposure may fail to influence neurocognitive plasticity, on the other hand, long-term early life bilingual exposure would influence children's cortical organization for language processing. For instance, by mid-childhood, bilingual children show greater activation in posterior temporo-parietal regions that support more automated lexical recognition, while monolinguals rely on greater activity in the left frontal regions (Arredondo et al, 2019a).…”