Mapping the neural patterns of verbal repetition: an activation likelihood estimation meta-analysis
摘要
Verbal repetition involves transforming heard speech into articulatory motor output and constitutes a core language function integrating receptive and expressive processes within tight temporal constraints. This integrative nature underlies its importance for language acquisition and learning and accounts for its diagnostic relevance in acquired and developmental language disorders. Despite extensive investigation, the consistent neural architecture supporting verbal repetition has remained insufficiently established due to methodological heterogeneity across studies. Here, we conducted a coordinate-based meta-analysis using Activation Likelihood Estimation (ALE) on 27 neuroimaging experiments (380 participants; 440 activation foci) to identify brain regions consistently engaged during verbal repetition in healthy adults, to compare word and pseudoword repetition, and to assess hemispheric lateralization. Across all conditions, verbal repetition consistently engaged a robust, bilaterally distributed fronto-temporo-parietal network encompassing auditory-phonological regions of the superior temporal cortex, sensorimotor cortices of the precentral and postcentral gyri, and medial frontal motor regions including the SMA and the preSMA. Lateralization analyses revealed a predominant left-hemispheric contribution across conditions, with a stronger leftward bias for pseudoword than for word repetition, despite largely bilateral engagement. Direct contrasts indicated stimulus-dependent modulation within this partially shared dorsal network: pseudoword repetition showed greater involvement of auditory associative, premotor, and subcortical regions, whereas word repetition preferentially engaged primary auditory and medial frontal motor regions. Together, these findings provide a comprehensive overview of the neural systems supporting verbal repetition, highlighting a shared dorsal auditory-motor network that is flexibly modulated as a function of stimulus familiarity.