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Modulation of verbal fluency networks by transcranial direct current stimulation (tDCS) in Parkinson’s disease

  • Joana B. Pereira
    Affiliations
    Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain

    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
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  • Carme Junqué
    Affiliations
    Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain

    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
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  • David Bartrés-Faz
    Correspondence
    Corresponding author. Tel.: +34 93 403 44 46; fax: +34 93 403 52 94.
    Affiliations
    Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain

    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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  • Maria J. Martí
    Affiliations
    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Parkinson’s disease and Movement Disorders Unit, Neurology Service, Institut Clínic de Neurociencies, Hospital Clínic de Barcelona, Spain

    Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
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  • Roser Sala-Llonch
    Affiliations
    Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain

    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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  • Yarko Compta
    Affiliations
    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Parkinson’s disease and Movement Disorders Unit, Neurology Service, Institut Clínic de Neurociencies, Hospital Clínic de Barcelona, Spain

    Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
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  • Carles Falcón
    Affiliations
    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
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  • Pere Vendrell
    Affiliations
    Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain

    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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  • Álvaro Pascual-Leone
    Affiliations
    Berenson-Allen Center for Non-Invasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA

    Institut Universitari de Neurorehabilitacio Guttmann-UAB, Badalona, Spain
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  • Josep Valls-Solé
    Affiliations
    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Laboratori d’Exploracions Neurofuncionals, Hospital Clinic de Barcelona, Spain
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  • Eduardo Tolosa
    Affiliations
    Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain

    Parkinson’s disease and Movement Disorders Unit, Neurology Service, Institut Clínic de Neurociencies, Hospital Clínic de Barcelona, Spain

    Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
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Published:February 23, 2012DOI:https://doi.org/10.1016/j.brs.2012.01.006

      Abstract

      Background

      Verbal fluency relies on the coordinated activity between left frontal and temporal areas. Patients with Parkinson’s disease (PD) present phonemic and semantic fluency deficits. Recent studies suggest that transcranial direct current stimulation (tDCS) enhances adaptative patterns of brain activity between functionally connected areas.

      Objective

      The aim of this study was to assess the differences in the effects induced by tDCS applied to frontal and temporo-parietal areas on phonemic and semantic fluency functional networks in patients with PD.

      Method

      Sixteen patients were randomized to receive tDCS to left dorsolateral prefrontal cortex (DLPFC) and left temporo-parietal cortex (TPC) in a counterbalanced order. Immediately following stimulation, patients underwent a verbal fluency paradigm inside a fMRI scanner. Changes induced by tDCS in activation and deactivation task-related pattern networks were studied using free-model independent component analyses (ICA).

      Results

      Functional connectivity in verbal fluency and deactivation task-related networks was significantly more enhanced by tDCS to DLPFC than to TPC. In addition, DLPFC tDCS increased performance on the phonemic fluency task, after adjusting for baseline phonemic performance.

      Conclusions

      These findings provide evidence that tDCS to specific brain regions induces changes in large scale functional networks that underlay behavioural effects, and suggest that tDCS might be useful to enhance phonemic fluency in PD.

      Keywords

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