Patterns of Cortical Activity in a Silent Single-Word Reading Task Depend on Word Frequency and Age-Related...

This study investigates how word frequency and age modulate the amplitude, temporal, and spatial patterns of cortical activation during silent single-word reading, as measured by magnetoencephalography (MEG). We recorded MEG data from 30 neurotypical adults and 30 typically developing children during a silent reading task involving high-frequency words, low-frequency words, and pseudowords, with cortical activation analyzed using event-related fields (ERF) and peak latency (PL). In both adults and children, high-frequency words elicited lower ERF amplitudes and faster processing times compared to low-frequency words and pseudowords. While similar neural regions were activated across stimulus types, children demonstrated significantly higher amplitudes and longer processing times than adults. These results indicate that word frequency significantly modulates the neural dynamics of reading, with high-frequency words processed more efficiently. Furthermore, the data suggest that the reading pathways in children are still maturing, as evidenced by their increased neural activation and delayed processing. This developmental difference, particularly the demonstration of frequency-dependent processing in the superior temporal gyrus of children, offers unique evidence for the maturation of distinct lexical and sublexical reading pathways, consistent with the dual-route cascaded theory.