Healthy
Conditions
Keywords
Theta-Burst stimulation (iTBS), Functional near-infrared spectroscopy (fNIRS), Concurrent TMS/fNIRS, Prefrontal hemodynamic response
Brief summary
Intermittent theta-burst stimulation (iTBS) is a promising treatment for major depressive disorder. However, fewer than 50% of patients show sufficient response. Therefore, the optimal treatment protocol is worth investigating. Recent studies show that the relationship between stimulation intensity and prefrontal hemodynamic response is not linear but in an inverse U-shape by exploring the hemodynamic changes before and after iTBS. Concurrent transcranial magnetic stimulation (TMS)/functional near-infrared spectroscopy (fNIRS) setup allows the investigators to observe the prefrontal hemodynamic response during stimulation. The aim of this study is to investigate the effects of different intensities on brain activity during and after the stimulation using fNIRS.
Detailed description
Please refer to the full proposal
Interventions
The iTBS will be applied over lDLPFC with three different intensities. The investigators put the NIRS probe under the TMS coil to detect the hemodynamic signal simultaneously, and the applied rMT was adjusted based on Stokes et al., 2007. The equation is AdjMT% = MT + 2.8 \* (Dsitex - Dm1), and the thickness of the probe is 6mm, therefore, 2.8\*6=16.8(%) were added to the normal intensity.
Sponsors
The Hong Kong Polytechnic University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Masking description
Participants will not be informed of the stimulation intensities.
Intervention model description
Healthy volunteers will receive iTBS three times with three different intensities separated by one week to investigate the prefrontal hemodynamic response to different stimulation intensities.
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Right-handed
Exclusion criteria
* history of epilepsy, seizures, or convulsions * current or past diagnosis of neurological disorders, such as head injuries, strokes, encephalitis, epilepsy, Parkinson's, or Alzheimer's * current or past diagnosis of psychiatric disorders, such as depression, anxiety, schizophrenia, or autism * with metal implants, such as a cochlear implant, neurostimulator, or cardiac pacemaker
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Oxygenated hemoglobin (HbO) change compared to baseline | During and post TBS-fNIRS measurement, up to 3 months | iTBS-induced HbO change in the DLPFC before, during and after stimulation |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Deoxygenated hemoglobin (HbR) Change compared to baseline | During and post TBS-fNIRS measurement, up to 3 months | iTBS-induced HbR change in the DLPFC before, during and after stimulation |
| Oxygen saturation change compared to baseline | During and post TBS-fNIRS measurement, up to 3 months | iTBS-induced oxygen saturation change in the DLPFC before, during and after stimulation |
Countries
Hong Kong
Outcome results
None listed