Processing demands upon cognitive, linguistic, and articulatory functions promote grey matter plasticity in the adult multilingual brain: Insights from simultaneous interpreters

• Published in: Cortex Vol. 54; no. May; pp. 179 - 189
• Main Authors: Elmer, Stefan, Hänggi, Jürgen, Jäncke, Lutz
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2014; Elsevier
• Subjects: Adult; Anatomical correlates of behavior; Anatomy; Articulation; Behavioral psychophysiology; Biological and medical sciences; Brain - physiology; Brain Mapping; Cognition - physiology; Cognitive control; Female; Fundamental and applied biological sciences. Psychology; Gray Matter - physiology; Grey matter volume; Humans; Image Processing, Computer-Assisted; Language; Linguistic functions; Magnetic Resonance Imaging; Male; Middle Aged; Multilingual speech processing; Multilingualism; Neuronal Plasticity - physiology; Plasticity; Problem Solving - physiology; Production and perception of spoken language; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Simultaneous interpreters; Speech - physiology; Voxel-based morphometry; Articulation; Multilingual speech processing; Simultaneous interpreters; Voxel-based morphometry; Grey matter volume; Plasticity; Linguistic functions; Anatomy; Cognitive control; Human; Volumetric analysis; Multilingualism; Speech articulation; Interpreter; Grey matter; Central nervous system; Cognition; Mental load; Encephalon; Language; Information processing; Adult; Speech; Morphometry
• ISSN: 0010-9452; 1973-8102
• DOI: 10.1016/j.cortex.2014.02.014

Until now, considerable effort has been made to determine structural brain characteristics related to exceptional multilingual skills. However, at least one important question has not yet been satisfactorily addressed in the previous literature, namely whether and to which extent the processing demands upon cognitive, linguistic, and articulatory functions may promote grey matter plasticity in the adult multilingual brain. Based on the premise that simultaneous interpretation is a highly demanding linguistic task that places strong demands on executive and articulatory functions, here we compared grey matter volumes between professional simultaneous interpreters (SI) and multilingual control subjects. Thereby, we focused on a specific set of a-priori defined bilateral brain regions that have previously been shown to support neurocognitional aspects of language control and linguistic functions in the multilingual brain. These regions are the cingulate gyrus, caudate nucleus, frontal operculum (pars triangularis and opercularis), inferior parietal lobe (IPL) (supramarginal and angular gyrus), and the insula. As a main result, we found reduced grey matter volumes in professional SI, compared to multilingual controls, in the left middle-anterior cingulate gyrus, bilateral pars triangularis, left pars opercularis, bilateral middle part of the insula, and in the left supramarginal gyrus (SMG). Interestingly, grey matter volume in left pars triangularis, right pars opercularis, middle-anterior cingulate gyrus, and in the bilateral caudate nucleus was negatively correlated with the cumulative number of interpreting hours. Hence, we provide first evidence for an expertise-related grey matter architecture that may reflect a composite of brain characteristics that were still present before interpreting training and training-related changes.