Impact of Theta Burst Stimulation Over the Left Dorsolateral Prefrontal Cortex on Language Switching and Cognitive Flexibility
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Languages
- Sponsor
- Jean-Marie Annoni
- Enrollment
- 41
- Locations
- 1
- Primary Endpoint
- RTs for Picture Naming With the Factors Language (L1, L2) and Block (Switching, Non-Switching)
- Status
- Completed
- Last Updated
- 6 years ago
Overview
Brief Summary
The purpose of this study is to investigate whether theta burst stimulation (TBS) over the left dorsolateral prefrontal cortex (DLPFC) influences language switching and cognitive flexibility. The experimental paradigm will assess the impact of inhibitory and excitatory prefrontal stimulation by TBS versus sham-TBS over the DLPFC in healthy bilinguals.
Detailed Description
Background: Clinical observations and neuroimaging studies seem to confirm the role of executive functions and frontal structures in language processing in bilingual subjects. Repetitive transcranial magnetic stimulation, such as for example theta burst stimulation (TBS), is increasingly being used as a valuable tool for neuroscientists investigating the underlying mechanisms of cognitive functions. Case studies have shown a change in language switching after bilingual patients received repetitive magnetic stimulation to the left DLPFC. However, there is no study investigating the effect of TBS applied to the DLPFC on language switching in healthy participants. Procedure: A planned total of 40 unbalanced bilingual participants will be included. Half of the participants will receive inhibitory theta burst stimulation (continuous TBS), the other half excitatory theta burst stimulation (intermittent TBS). After TBS, different language and nonverbal tasks will be performed while an EEG is measured. Before being stimulated, each subject will conduct the same tasks with a sham-TBS as a baseline measure.
Investigators
Jean-Marie Annoni
Prof. Dr. med.
University of Fribourg
Eligibility Criteria
Inclusion Criteria
- •L1 (Swiss)German, 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 head
- •history of neurological diseases or severe psychiatric disorders
- •drug use (alcohol, psychoactive medication)
- •strong headache
- •pregnancy
Outcomes
Primary Outcomes
RTs for Picture Naming With the Factors Language (L1, L2) and Block (Switching, Non-Switching)
Time Frame: Within 30 minutes after intervention
Picture naming with the factors Language (L1, L2) and Block (Switching, Non-Switching): Speech onset times (msec) L1 refers to the mother tongue. L2 refers to the late acquired (\> age 7) second language. Switching Block refers to a language switching block with picture naming alternated between the mother tongue and the second language. Non-Switching Block refers to a block of picture naming either only in the mother or only in the second language.
Secondary Outcomes
- Nonverbal Switching(Within 30 minutes after intervention)