Impact of Theta Burst Stimulation Over the Left DLPFC on Language Switching

Jean-Marie Annoni

Status: Completed

Conditions: Languages

Treatments: Device: continuous theta burst stimulation (cTBS); Device: intermittent theta burst stimulation (iTBS); Device: Sham iTBS; Device: Sham cTBS

Study type: Interventional

Funder types: Other

Identifiers

NCT03148470

SNF325130_156937_4

Details and patient eligibility

About

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.

Full 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.

Enrollment: 41 patients

Sex: All

Ages: 18 to 45 years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Factorial Assignment

Masking: Double Blind

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41 participants in 2 patient groups

intermittent theta burst stimulation

Experimental group

Description:

intermittent theta burst stimulation (iTBS) + Sham iTBS

Treatment:

Device: Sham iTBS

Device: intermittent theta burst stimulation (iTBS)

continuous theta burst stimulation

Experimental group

Description:

continuous theta burst stimulation (cTBS) + Sham cTBS

Treatment:

Device: continuous theta burst stimulation (cTBS)

Device: Sham cTBS