Effect of rTMS of the Dorsolateral Prefrontal Cortex on Language Production in Healthy Participants

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) on language production.

Detailed Description
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Background: Several studies investigating healthy or clinical populations have shown that (r)TMS applied over the dorsolateral prefrontal cortex (DLPFC) has an effect on language-related processes such as verbal working memory (Osaka et al., 2007), sentence comprehension (Cotelli et al., 2011) and language switching (Holtzheimer et al., 2005, Nardone et al., 2011). Clinical observations and neuroimaging studies seem to confirm the role of executive functions and frontal structures in language processing in monolingual and bilingual subjects (e.g. Fabbro et al., 2000, Abutalebi & Green 2007). However, only few studies investigated the effects of modulation of cognitive control-networks on lexical access. Aim and procedure: The study will investigate the role of the DLPFC and executive functioning in L1 and L2 language processing. The core question is whether rTMS over the DLPFC will influence lexical access and language production. Each participant will take part in two sessions: 1. rTMS session 2. Sham rTMS session. After the application of rTMS/Sham rTMS, the participants will conduct two language tasks (translation, picture naming) and a non-verbal task, while the EEG is recorded.

Official Title
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Role of Executive Function in Language: an Experimental and Clinical Approach With Application to Mother Language and Second Language

Conditions
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Language

Intervention / Treatment
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* Device: rTMS
* Device: Sham rTMS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: L1 French, knowledge of English as a foreign language 18-45 years of age Right-handedness Exclusion Criteria: epilepsy /family history of epilepsy brain surgery, traumatic brain injuries cardiac pacemaker, metallic objects in the body history of neurological diseases or psychiatric disorders drug use (alcohol, psychoactive medication) developmental language disorder

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: rTMS<br> | Device: rTMS<br>* repetitive TMS (rTMS) can lead to temporary increases or decreases (depending on the protocol used) in excitability of the targeted area. This change in excitability has been shown to last beyond the duration of the stimulation.<br>|
| Sham Comparator: Sham rTMS<br> | Device: Sham rTMS<br>* Sham rTMS (or placebo rTMS) refers to a control condition in which no physiological effect on the targeted cortical region occurs.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Language production | Picture naming task and word translation task | within 30 mins after rTMS/sham rTMS | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| non-verbal executive functions task |  | within 30 mins after rTMS/sham rTMS | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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language, DLPFC, rTMS, Executive Functions