Language learning in the adult brain: disrupting the dorsolateral prefrontal cortex facilitates word-form learning

Smalle, Eleonore H.M.; Panouilleres, Muriel; Szmalec, Arnaud; M�tt�nen, Riikka

Abstract

Adults do not learn languages as easily as children do. It has been hypothesized that the late-developing prefrontal cortex that supports executive functions competes with procedural learning mechanisms that are important for language learning. To address this hypothesis, we tested whether a temporary neural disruption of the left Dorsolateral Prefrontal Cortex (DLPFC) can improve implicit, procedural learning of word-forms in adults. Young adults were presented with repeating audio-visual sequences of syllables for immediate serial recall in a Hebb repetition learning task that simulates word-form learning. Inhibitory theta-burst Transcranial Magnetic Stimulation was applied to the left DLPFC or to the control site before the Hebb task. The DLPFC-disrupted group showed enhanced learning of the novel phonological sequences relative to the control group. Moreover, learning was negatively correlated with executive functions that rely on the DLPFC in the control group, but not in the DLPFC-disrupted group. The results support the hypothesis that a mature prefrontal cortex competes with implicit learning of word-forms. The findings provide new insight into the competition between brain mechanisms that contribute to language learning in the adult brain.

Citation

Smalle, E. H., Panouilleres, M., Szmalec, A., & Möttönen, R. (in press). Language learning in the adult brain: disrupting the dorsolateral prefrontal cortex facilitates word-form learning. Scientific Reports, 7(1), Article 13966. https://doi.org/10.1038/s41598-017-14547-x

• Journal Article Type: Article
• Acceptance Date: Oct 12, 2017
• Online Publication Date: Oct 25, 2017
• Deposit Date: Dec 5, 2017
• Publicly Available Date: Dec 5, 2017
• Journal: Scientific Reports
• Electronic ISSN: 2045-2322
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Issue: 1
• Article Number: 13966
• DOI: https://doi.org/10.1038/s41598-017-14547-x
• Public URL: https://nottingham-repository.worktribe.com/output/889305
• Publisher URL: https://www.nature.com/articles/s41598-017-14547-x
• Contract Date: Dec 5, 2017