HealthyNCT06104462
Exploring the Cortical Hemodynamic Variability of Prefrontal iTBS: a Concurrent TBS/fNIRS Study
A study testing Intermittent theta burst stimulation (iTBS) in people with Healthy, run by The Hong Kong Polytechnic University at 1 site in Hong Kong.
Trial summary
An increasing number of studies have used the intermittent theta-burst stimulation (iTBS) protocol to investigate neural plasticity non-invasively in the prefontal cortex in healthy humans and in patients with psychiatric disorders. Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy
- What is being tested?
- Intermittent theta burst stimulation (iTBS)
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteHong Kong
- Study dates
- 18 Oct 2023to 31 Dec 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- healthiness based on history and psychiatric assessment
- being able to hear and understand the verbal instructions
- completed at least 6 years of formal education
Who cannot join
- a current or past diagnosis of psychiatric, neurological disorders, or severe internal illness
- any conditions that will contraindicate to iTBS or fNIRS
- psychiatric disorders in their first-degree relatives
- pregnancy
Trial locations and contacts
1 site in 1 country.
About this study
An increasing number of studies have used the intermittent theta-burst stimulation (iTBS) protocol to investigate neural plasticity non-invasively in the prefontal cortex in healthy humans and in patients with psychiatric disorders. However, the variability in the neurophysiological response to iTBS stimulation is high. The cause of this variability is multifactorial and to some degree still unknown. Therefore, the current study explores inter- and intra-individual factors that are potentially moderating iTBS-induced excitability changes. A greater understanding of these determinants would be highly valuable for optimizing the therapeutic application of iTBS.
Read the detailed description
The investigators will measure the cortical excitability induced by iTBS with concurrent TBS/fNIRS technique in the same healthy individuals on multiple testing days. Meanwhile, several potential inter- (age, gender, etc.) and intra-individual factors (daily mood, daily physical activity levels, etc.) recently identified in non-invasive transcranial brain stimulation studies will be assessed before applying iTBS to the same individual on each testing day.
- Conditions
- Healthy
- Being tested
- Intermittent theta burst stimulation (iTBS)
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Intermittent theta burst stimulation (iTBS)Device
Also called Repetitive transcranial magnetic stimulation (rTMS)
The iTBS protocol consists of 20 trains of stimulation. Each train comprises ten 3-pulse bursts, delivered at an intra-burst frequency of 50 Hz, with a 5 Hz overall frequency, followed by 8 seconds of rest. A total of 600 pulses (10*3*20) will be administered in this 3-minute iTBS protocol. Concurrent TBS/fNIRS stimulation will be applied over the left DLPFC at an intensity of 90% of the resting motor threshold (RMT), which is considered appropriate to ensure compliance and elicit robust DLPFC activation.
Considering that the fNIRS optode beneath the coil increases the distance between the TMS coil and the skull by 10 mm, we will use the equation AdjMT% = MT + 2.8 * (Dsitex - Dm1). Therefore, 2.8 * 10 = 28% will be added to the normal intensity. The stimulation site over the DLPFC will be determined by the MNI coordinate (x-38, y+44, z+26) reported in previous studies.
| Study group | Role | What they receive |
|---|---|---|
| Cortical hemodynamic variability of iTBS and its courses | Experimental | A group of healthy adults shall undergo repeated experimental visits with concurrent TBS/fNIRS (3≤repetition≤15). An interval of at least two days (48 hours) between the visits is required to minimize carry-over effects from the iTBS protocols.
Inter- (age, gender, personality inventory, etc.) and intra-individual factors (daily mood, daily sleep quality, physical activity levels, etc.) that are potentially moderating iTBS-induced excitability changes will be explored. Receives: Device: Intermittent theta burst stimulation (iTBS) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Oxygenated hemoglobin (HbO) change compared to baseline
iTBS-induced HbO change in the DLPFC before, during and after stimulation
Measured: During and post TBS-fNIRS measurement, up to 3 months
Secondary outcomes (2)
Deoxygenated hemoglobin (HbR) change compared to baseline
iTBS-induced HbR change in the DLPFC before, during and after stimulation
Measured: During and post TBS-fNIRS measurement, up to 3 months
Oxygen saturation change compared to baseline
iTBS-induced oxygen saturation change in the DLPFC before, during and after stimulation
Measured: During and post TBS-fNIRS measurement, up to 3 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Oct 2023
- Study start18 Oct 2023
- Primary completion31 Dec 2024
- Study completion31 Dec 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HealthyStudies of the same condition, open and under way.
- More trials run by The Hong Kong Polytechnic UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 40 participants (actual)
Sponsor and investigators
- Lead sponsor
- The Hong Kong Polytechnic University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Dr Georg Kranz, The Hong Kong Polytechnic University
- Investigators
- Georg Kranz, PhD, Principal investigator, The Hong Kong Polytechnic University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06104462
- Sponsor's protocol ID
- HSEARS20220812002-02
- Status last verified
- Sep 2026
- First submitted
- 20 Oct 2023
- Last updated
- 17 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: IPD may be shared upon request
Study at a glance
From the registry record, last updated by the sponsor on 17 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Exploring the Cortical Hemodynamic Variability of Prefrontal iTBS: a Concurrent TBS/fNIRS Study
- ClinicalTrials.gov ID
- NCT06104462
- Acronym / sponsor ID
- HSEARS20220812002-02
- Conditions
- Healthy
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 40 participants (actual)
- Lead sponsor
- The Hong Kong Polytechnic UniversityUniversity, hospital or other
- Study start
- 18 Oct 2023 (actual)
- Primary completion
- 31 Dec 2024 (actual)
- Study completion
- 31 Dec 2024 (actual)
- First posted
- 27 Oct 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
An increasing number of studies have used the intermittent theta-burst stimulation (iTBS) protocol to investigate neural plasticity non-invasively in the prefontal cortex in healthy humans and in patients with psychiatric disorders. However, the variability in the neurophysiological response to iTBS stimulation is high. The cause of this variability is multifactorial and to some degree still unknown. Therefore, the current study explores inter- and intra-individual factors that are potentially moderating iTBS-induced excitability changes. A greater understanding of these determinants would be highly valuable for optimizing the therapeutic application of iTBS.
Detailed description
The investigators will measure the cortical excitability induced by iTBS with concurrent TBS/fNIRS technique in the same healthy individuals on multiple testing days. Meanwhile, several potential inter- (age, gender, etc.) and intra-individual factors (daily mood, daily physical activity levels, etc.) recently identified in non-invasive transcranial brain stimulation studies will be assessed before applying iTBS to the same individual on each testing day.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Cortical hemodynamic variability of iTBS and its courses | Experimental | Device: Intermittent theta burst stimulation (iTBS)A group of healthy adults shall undergo repeated experimental visits with concurrent TBS/fNIRS (3≤repetition≤15). An interval of at least two days (48 hours) between the visits is required to minimize carry-over effects from the iTBS protocols. Inter- (age, gender, personality inventory, etc.) and intra-individual factors (daily mood, daily sleep quality, physical activity levels, etc.) that are potentially moderating iTBS-induced excitability changes will be explored. |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- healthiness based on history and psychiatric assessment
- being able to hear and understand the verbal instructions
- completed at least 6 years of formal education
Key exclusion criteria (4 listed)
- a current or past diagnosis of psychiatric, neurological disorders, or severe internal illness
- any conditions that will contraindicate to iTBS or fNIRS
- psychiatric disorders in their first-degree relatives
- pregnancy
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Intermittent theta burst stimulation (iTBS)Also: Repetitive transcranial magnetic stimulation (rTMS)The iTBS protocol consists of 20 trains of stimulation. Each train comprises ten 3-pulse bursts, delivered at an intra-burst frequency of 50 Hz, with a 5 Hz overall frequency, followed by 8 seconds of rest. A total of 600 pulses (10*3*20) will be administered in this 3-minute iTBS protocol. Concurrent TBS/fNIRS stimulation will be applied over the left DLPFC at an intensity of 90% of the resting motor threshold (RMT), which is considered appropriate to ensure compliance and elicit robust DLPFC activation. Considering that the fNIRS optode beneath the coil increases the distance between the TMS coil and the skull by 10 mm, we will use the equation AdjMT% = MT + 2.8 * (Dsitex - Dm1). Therefore, 2.8 * 10 = 28% will be added to the normal intensity. The stimulation site over the DLPFC will be determined by the MNI coordinate (x-38, y+44, z+26) reported in previous studies. | Device | Cortical hemodynamic variability of iTBS and its courses |
Primary outcome
Oxygenated hemoglobin (HbO) change compared to baseline
Time frame: During and post TBS-fNIRS measurement, up to 3 months
iTBS-induced HbO change in the DLPFC before, during and after stimulation
2 secondary outcomes
Deoxygenated hemoglobin (HbR) change compared to baseline
Time frame: During and post TBS-fNIRS measurement, up to 3 months
Oxygen saturation change compared to baseline
Time frame: During and post TBS-fNIRS measurement, up to 3 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Sep 2026.
- Individual participant dataSharing planned: Yes. IPD may be shared upon request
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Georg Kranz, PhD principal investigator
The Hong Kong Polytechnic University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Intermittent theta burst stimulation (iTBS) in people with Healthy, run by The Hong Kong Polytechnic University at 1 site in Hong Kong.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 17 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Oxygenated hemoglobin (HbO) change compared to baseline (time frame: During and post TBS-fNIRS measurement, up to 3 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Sep 2026; AzTrials last refreshed its copy on 2 Nov 2026.