Skip to main content
OpenTrials
Completed

NCT Number: NCT03148470

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

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.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Languages Behavior Communication Language

Age range

18 year–45 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Laboratory for Cognitive and Neurological Sciences

Fribourg, 1700, Switzerland

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Sham iTBS

Device

Placebo stimulation for the iTBS group

Sham cTBS

Device

Placebo stimulation for the cTBS group

intermittent theta burst stimulation (iTBS)

Device

Excitatory theta burst stimulation

Continuous theta burst stimulation (cTBS)

Device

inhibitory theta burst stimulation

Primary outcomes

  1. 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

  1. Nonverbal Switching

    Time frame: Within 30 minutes after intervention

    Nonverbal Switching: response times

Sponsors and collaborators

Lead sponsor

Jean-Marie Annoni

Other

Registry information

Official study title

Impact of Theta Burst Stimulation Over the Left Dorsolateral Prefrontal Cortex on Language Switching and Cognitive Flexibility

Important dates

Study start
2016
Primary completion
2018
Study completion
2019
First posted
May 11, 2017
Registry last updated
Apr 22, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.