Cortical Dynamics of Inhibitory Control: A Concurrent tDCS-MEG Study
- Conditions
- Impulsive Behavior
- Interventions
- Device: Sham tDCSDevice: Anodal tDCS
- Registration Number
- NCT03484377
- Lead Sponsor
- Najat Khalifa
- Brief Summary
This study aims to use concurrent Transcranial Direct Current Stimulation (tDCS) and Magnetoencephalography (MEG) with measures of impulsivity to examine the neurobiological underpinnings of rapid response impulsivity (RRI) and how these can be modified using tDCS in healthy subjects.
- Detailed Description
Concurrent tDCS-MEG parallel arms single-blinded experimental design (right anodal v sham tDCS) will be employed in this study. The study will be conducted at the University of Nottingham, using a sample of student volunteers. This study aims to examine the influence of anodal tDCS on beta-band and alpha-band oscillatory activities, using an anti-saccade task administered before, during and after tDCS stimulation. It can potentially help understand the neurobiological mechanisms underpinning rapid response impulsivity and how these can be influenced by tDCS.
The research hypotheses are that (i) a generalised mechanism for top-down inhibitory control will play a vital role, whereby prefrontal beta-band activity initiates alpha-band activity for functional inhibition over the frontal eye fields and other areas in the neurocircuitry involved in RRI; (ii) anodal tDCS (as opposed to sham) delivered over the right DLPFC will enhance this mechanism; and (iii) there will be no significant correlations between measures of self-report impulsivity and performance on the anti-saccade task and measures of oscillatory activity.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 36
- University students and staff
- Aged 18-40
- Individuals with epilepsy and other neurological conditions, history of significant head injury, substance misuse, major mental disorder and those receiving psychotropic medication.
- Contraindications to use of Magnetic Resonance (pacemakers, metal implants, aneurysm clips)
- Pregnancy.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Sham tDCS Sham tDCS The sham (cathodal) electrode will be placed over the left supraorbital ridge. The current will be delivered only in the first 10 seconds, after which the stimulation will cease but with the electrodes still in place throughout the session. Anodal tDCS Anodal tDCS The anodal tDCS electrode will be placed over the area corresponding to the right DLPFC (F4 of the EEG10-20 international system). The anodal tDCS condition will use a constant current of 2mA, delivered via gradual increase and decrease over 10 seconds at the onset and offset of stimulation (current ramps), respectively.
- Primary Outcome Measures
Name Time Method Total number of correct anti-saccade (AS) trials Change from baseline after 20 minutes of tDCS A measure of rapid response impulsivity (inhibitory control)
- Secondary Outcome Measures
Name Time Method Total number of correct pro-saccade (PS) trials Change from baseline after 20 minutes of tDCS A behavioral measure of rapid response impulsivity (inhibitory control)
Saccade latency for pro-saccade (PS) trials Change from baseline after 20 minutes of tDCS A behavioral measure of rapid response impulsivity (inhibitory control)
Alpha and Beta band activity Change from baseline after 20 minutes of tDCS A Cortical measure of inhibitory control recorded using Magnetoencephalography (MEG). MEG is a brain imaging technique.
Saccade latency for anti-saccade (AS) trials Change from baseline after 20 minutes of tDCS A behavioral measure of rapid response impulsivity (inhibitory control)
Total Scores on the UPPS+P Impulsive Behaviour Scale Baseline A self-report measure of impulsivity
Trial Locations
- Locations (1)
University of Nottingham
🇬🇧Nottingham, Notts, United Kingdom