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A diffusion model approach to analyzing performance on the Flanker task: The role of the DLPFC

Published online by Cambridge University Press:  17 September 2018

SERGIO MIGUEL PEREIRA SOARES ,
GABRIEL ONG ,
JUBIN ABUTALEBI Open the ORCID record for JUBIN ABUTALEBI [Opens in a new window] ,
NICOLA DEL MASCHIO ,
DAVID SEWELL  and
BRENDAN WEEKES
SERGIO MIGUEL PEREIRA SOARES
Affiliation:
Laboratory for Communication Science, Faculty of Education, University of Hong Kong
GABRIEL ONG*
Affiliation:
School of Psychological Science, University of Melbourne, Parkville, Australia
JUBIN ABUTALEBI
Affiliation:
Centre for Neurolinguistics and Psycholinguistics (CNPL), University Vita-Salute San Raffaele, Italy Laboratory for Communication Science, Faculty of Education, University of Hong Kong
NICOLA DEL MASCHIO
Affiliation:
Centre for Neurolinguistics and Psycholinguistics (CNPL), University Vita-Salute San Raffaele, Italy
DAVID SEWELL
Affiliation:
University of Queensland, St Lucia, Australia
BRENDAN WEEKES
Affiliation:
School of Psychological Science, University of Melbourne, Parkville, Australia Laboratory for Communication Science, Faculty of Education, University of Hong Kong Primary Investigator State Key Laboratory for Brain and Cognitive Sciences
*
Address for correspondence: Gabriel Ong, School of Psychological Sciences, University of Melbourne, Melbourne, Australiaghong@student.unimelb.edu.au
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Abstract

The anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC) are involved in conflict detection and conflict resolution, respectively. Here, we investigate how lifelong bilingualism induces neuroplasticity to these structures by employing a novel analysis of behavioural performance. We correlated grey matter volume (GMV) in seniors reported by Abutalebi et al. (2015) with behavioral Flanker task performance fitted using the diffusion model (Ratcliff, 1978). As predicted, we observed significant correlations between GMV in the DLPFC and Flanker performance. However, for monolinguals the non-decision time parameter was significantly correlated with GMV in the left DLPFC, whereas for bilinguals the correlation was significant in the right DLPFC. We also found a significant correlation between age and GMV in left DLPFC and the non-decision time parameter for the conflict effect for monolinguals only.

We submit that this is due to cumulative demands on cognitive control over a lifetime of bilingual language processing.

Keywords

agingbilingualismcognitive controlcognitive reserveDLPFCVBM

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Type
Research Article
Information
Bilingualism: Language and Cognition , Volume 22 , Issue 5 , November 2019 , pp. 1194 - 1208
Copyright
Copyright © Cambridge University Press 2018 

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Footnotes

This research was supported by the GRF grant 754412 awarded by the Research Grants Council of Hong Kong and Seed Grants from the University of Hong Kong.

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