standard MRI examination without direct medical applications This research utilizes brain imaging techniques with healthy participants only without any medical applications
Conditions
Interventions
None listed
Sponsors
Universiteit Leiden
Eligibility
Age
18 Years to 99 Years
Inclusion criteria
Inclusion criteria: Participants will be healthy, volunteer, right-handed Dutch-English bilinguals, without any report and history of neurological or psychiatric problems and no counter-indications to MRI. Their age will not be more than thirty.
Exclusion criteria
Exclusion criteria: Left-handed volunteers, balanced bilinguals, the ones who are more than 30 years old, and have any report and history of neurological or psychiatric problems, will be excluded from this study. Potential participants will be pre-screened for contraindications for fMRI, which include metal implants, heart arrhythmia, claustrophobia, and possible pregnancy (in females). The ones with the positive results in pre-screen section will be excluded.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The main endpoint of the study is to delineate the way cognitive control contributes to absence of standard language effect and reversed language effect in bilinguals, when producing L1 and L2 lexical items. We measure the hemodynamic response, or rather indirect consequences of neural activity, in order to have access to detailed patterns of activity in brain when participants perform different sections of the experiment. In doing so, via General Linear Model, voxels with significant activations will be detected. Our particular foci will be in brain regions involved in cognitive control, namely, prefrontal cortex, ACC (Abutalebi et al., 2013; Braver et al., 2001; Bunge et al., 2002; Reverberi et al, 2015), inferior parietal cortex (Braver et al., 2001; Bunge et al., 2002), as well as basal ganglia (Middleton & Strick, 2000). Voxels with significant activations in brain regions involved in cognitive control will be compared a) in pre-switch, in which there is standard language effect (L1 is processed quicker than L2) and in post-switch with new stimuli, in which there is lack of standard language effect (there is no difference between L1 and L2 processing speed) b) in pre-switch, in which there is standard language effect (L1 is processed quicker than L2) and in post-switch with old stimuli, in which there is reversed language effect (L2 is processed quicker than L1). By making these comparisons we will detect how voxels with significant activations in pre-switch section of the experiment * in which there is standard language effect * change activation in post-switch with new stimuli, in which there is lack of standard language effect, and in post-switch with old stimuli, in which there is reversed language effect. In fact, via seed based approach PPI, the patterns of functional connectivity in three sections of the experimental task (pre-switch in which there is standard language effect, post-switch with old stimuli in which there is revers | — |
Secondary
| Measure | Time frame |
|---|---|
| The secondary endpoint of this study is to define any differences in terms of the strength of functional connectivity in brain areas involved in cognitive control, between participants who in post-switch section (with old stimuli) of the experiment reply to the first language faster than the ones who do it more slowly. In fact, participants who reply to the first language more slowly will show the reversed language effect more than the ones who reply to the first language faster. We are interested to know what exact neural mechanism marks one group with more reversed language effect than the other group. By using PPI, we will analyze connectivity in control network - prefrontal cortex, ACC (Abutalebi et al., 2013; Braver et al., 2001; Bunge et al., 2002; Reverberi et al, 2015), inferior parietal cortex (Braver et al., 2001; Bunge et al., 2002), as well as basal ganglia (Middleton & Strick, 2000) - for task-based fMRI data between these two groups of participants; in addition, we will use multivariate, seed-based approach to assess functional connectivity in three resting state networks that are known to be related to executive control (cognitive control including) (Grady,Luk, Craik, & Bialystok, 2015; Pliatsikas, & Luk, 2016) between these two groups of participants. These analyses will be done to understand how the correlation and strength of functional connectivity in brain areas involved in cognitive control, in both task-based fMRI and resting state fMRI are different between participants who show more reversed language effect than the ones with less degree of this effect. The three resting state networks that are of interest in this research include: - the frontoparietal control network (FPC), including dorsolateral and inferior frontal regions and inferior parietal regions (Spreng, Sepulcre, Turner, Stevens & Schacter, 2013), - the salience network (SLN), including the anterior insula, the dorsal anterior cingulate gyrus and the supra | — |
Countries
Netherlands
Outcome results
None listed