Exploring the Cortical Hemodynamic Variability of Prefrontal iTBS: a Concurrent TBS/fNIRS Study

Healthy Clinical Trial

Official title:

Exploring the Cortical Hemodynamic Variability of Prefrontal iTBS: a Concurrent TBS/fNIRS Study

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06104462
• Other study ID #: HSEARS20220812002-02
• Status: Recruiting
• Phase: N/A
• Start date: October 18, 2023
• Est. completion date: April 2024

Study information

• Verified date: February 2024
• Source: The Hong Kong Polytechnic University
• Contact: Georg Kranz, PhD
• Phone: 2766
• Email: georg.kranz[@]polyu.edu.hk
• Is FDA regulated: No
• Study type: Interventional

Clinical 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. 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.

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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 40
• Est. completion date: April 2024
• Est. primary completion date: April 2024
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• healthiness based on history and psychiatric assessment

• being able to hear and understand the verbal instructions

• completed at least 6 years of formal education

Exclusion Criteria:

• 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

Related Conditions & MeSH terms

• Healthy

Intervention

Device:
• Intermittent theta burst stimulation (iTBS)
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.

Locations

Country	Name	City	State
Hong Kong	The Hong Kong Polytechnic University	Hong Kong

Sponsors (1)

Lead Sponsor	Collaborator
The Hong Kong Polytechnic University

Country where clinical trial is conducted

Hong Kong, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Oxygenated hemoglobin (HbO) change compared to baseline	iTBS-induced HbO change in the DLPFC before, during and after stimulation	During and post TBS-fNIRS measurement, up to 3 months
Secondary	Deoxygenated hemoglobin (HbR) change compared to baseline	iTBS-induced HbR change in the DLPFC before, during and after stimulation	During and post TBS-fNIRS measurement, up to 3 months
Secondary	Oxygen saturation change compared to baseline	iTBS-induced oxygen saturation change in the DLPFC before, during and after stimulation	During and post TBS-fNIRS measurement, up to 3 months