Effect of Neuroplasticity Modulation in tDCS Treatment Response Among Schizophrenia Patients With Auditory Hallucination

NCT ID: NCT04629352

Last Updated: 2025-05-22

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 72 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-04-02
• Study Completion Date: 2026-08-31

Brief Summary

Schizophrenia is a severe neuropsychiatric disorder of the brain and is also one of the top ten disabling diseases. A common symptom of schizophrenia (SCZ) is hearing voices inside one's heads which others do not. Despite adequate medication, SCZ patients may continue to hear voices that are often rude or unfriendly and cause distress to the patients. Transcranial direct current stimulation (tDCS) is a safe, non-invasive brain stimulation technique that reduces 'hearing voices'. However, how and why add-on tDCS works is unclear. The brain can change itself in response to its environment; this is called neuroplasticity. tDCS possibly changes the brain's environment and/or enhances the brain's ability to respond favourably to its environment. This theory will be examined here by studying changes in brain functions before and after giving tDCS to schizophrenia patients hearing voices. The aim of this study is to examine the brain's neuroplasticity potential as the biological phenomena driving treatment effects of tDCS in Schizophrenia patients with clinically significant and persistent auditory verbal hallucinations. The secondary aims are to answer whether the brain's neuroplasticity potential in schizophrenia patients can predict their responsivity to tDCS treatment for auditory verbal hallucinations, and if chronicity of illness effects tDCS treatment response.

The brain's neuroplasticity potential will be examined using neuroimaging and neurophysiological techniques that give information about the integrity of the brain's signal processing efficiency, the chemical concentration of certain bio-molecules within it, and how well different areas of the brain communicate with each other. With this information, the potential role of the brain's neuroplasticity potential in facilitating treatment effects of tDCS can be better understood. With this knowledge, it could be possible personalize tDCS treatment, profile tDCS responders and non-responders based on demographic and biological factors, and prescribe tDCS at the appropriate time within the illness course for maximal benefit to the SCZ patients.

Detailed Description

20-30% schizophrenia (SCZ) patients struggle with auditory verbal hallucinations (AVH) minimally responsive to pharmaceutical treatments. An add-on fronto-temporoparietal transcranial direct current stimulation (tDCS) is suggested to address persistent AVH in SCZ patients. High heterogeneity among existing randomized control trials for AVH treatment in SCZ and the lack of empirical studies investigating the tDCS action mechanism warrants a systematic investigation into the mechanistic basis of tDCS action.

This proposal aims to examine the potential for neuroplasticity modulation as the mechanistic factor behind the therapeutic effects of left fronto-temporo-parietal tDCS for treating clinically significant AVH in early-course and chronic SCZ patients. It has been proposed and demonstrated that more tDCS sessions over a shorter interval lead to rapid plasticity induction. Accelerated tDCS protocol delivers a higher number of tDCS sessions over a shorter duration. Accelerated protocol (5 sessions/day for 2 days, inter-session interval~20 minutes) for the treatment of AVH in SZ showed clinical improvement with concurrent changes in neurophysiological correlates of auditory hallucination pathophysiology. Specifically, this study will examine neuroplasticity potential as a biomarker for tDCS treatment response with an accelerated tDCS (acctDCS) protocol. Using a randomized, double-blind, sham-controlled parallel-arm, pre-post design, changes in neuroplasticity potential with tDCS treatment for AVH in SCZ will be assessed. The four composite primary outcome measures of this study are:

1. changes in N100-derived event-related-potential waveforms (neurophysiological),

2. changes glutamine-glutamate levels (neurochemical),

3. changes in resting-state functional connectivity (neuroimaging), and

4. reduction in AVH severity (clinical).

The secondary objectives of this study are:

1. exploring the correlation between neurobiological measures of neuroplasticity changes induced by tDCS and clinical improvement in AVH to indicate the nature and strength of the relationship between the two;

2. exploring the effect of verum (active) tDCS on early course versus late course SCZ patients will uncover if illness chronicity is a potential barrier to tDCS responsivity; and

3. utilizing disorder-related (age at illness onset, medication, the severity of the symptom, etc.) and biographic (age, sex, years of education, etc.) features of the study sample towards predicting neuroplasticity modulation in the study sample.

Conditions

Schizophrenia; Schizoaffective Disorder

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: QUADRUPLE

Study Groups

Verum Accelerated Transcranial Direct Current Stimulation (acctDCS)

Each SCZ patient will receive five sessions daily for two days, a 10-session course of tDCS \[anode: left-DLPFC (at F3) and cathode: left-TPJ (midway between C3 and P3); electrode size: 35cm2\]. For the Verum-tDCS condition, 2-mA of constant current will be delivered for 20 minutes, with additional ramp-up and ramp-down of 30 seconds each.

Group Type: EXPERIMENTAL

Verum Accelerated Transcranial Direct Current Stimulation (acctDCS)

Intervention Type: DEVICE

In verum transcranial direct current stimulation (tDCS), patient will receive five sessions daily for two days, a 10-session course of tDCS \[anode: left-DLPFC (at F3) and cathode: left-TPJ (midway between C3 and P3); electrode size: 35cm2\]. For Verum-tDCS condition, 2-mA of constant current will be delivered for 20-minutes, additional ramp-up and ramp-down of 20 seconds each.

Sham Accelerated Transcranial Direct Current Stimulation (tDCS)

Each SCZ patient will receive five sessions daily for two days, a 10-session course of tDCS \[anode: left-DLPFC (at F3) and cathode: left-TPJ (midway between C3 and P3); electrode size: 35cm2\]. For Sham-tDCS, no current will be delivered beyond the initial ramp-up time.

Group Type: PLACEBO_COMPARATOR

Sham Accelerated Transcranial Direct Current Stimulation (acctDCS)

Intervention Type: DEVICE

In sham transcranial direct current stimulation (tDCS), each SCZ patient will receive five sessions daily for two days, a 10-session course of tDCS \[anode: left-DLPFC (at F3) and cathode: left-TPJ (midway between C3 and P3); electrode size: 35cm2\]. However, no current will be delivered beyond initial ramp-up time though the tDCS device display will indicate that 2mA current is being applied.

Interventions

Verum Accelerated Transcranial Direct Current Stimulation (acctDCS)

In verum transcranial direct current stimulation (tDCS), patient will receive five sessions daily for two days, a 10-session course of tDCS \[anode: left-DLPFC (at F3) and cathode: left-TPJ (midway between C3 and P3); electrode size: 35cm2\]. For Verum-tDCS condition, 2-mA of constant current will be delivered for 20-minutes, additional ramp-up and ramp-down of 20 seconds each.

Intervention Type: DEVICE

Sham Accelerated Transcranial Direct Current Stimulation (acctDCS)

In sham transcranial direct current stimulation (tDCS), each SCZ patient will receive five sessions daily for two days, a 10-session course of tDCS \[anode: left-DLPFC (at F3) and cathode: left-TPJ (midway between C3 and P3); electrode size: 35cm2\]. However, no current will be delivered beyond initial ramp-up time though the tDCS device display will indicate that 2mA current is being applied.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Diagnosis of schizophrenia or schizoaffective disorder as per DSM-5 (American Psychiatric Association, 2013)
• Clinically Significant Auditory Verbal Hallucinations
• Right-handedness
• Written informed consent

Exclusion Criteria

• Features suggestive of a psychiatric emergency
• Any contraindication to tDCS procedures
• Pregnancy or post-partum status
• Left/Mixed Handedness

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 45 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

National Institute of Mental Health and Neuro Sciences, India

OTHER

Sponsor Role: lead

Responsible Party

Anushree Bose

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Anushree Bose, PhD

Role: PRINCIPAL_INVESTIGATOR

Department of Psychiatry, NIMHANS, Bengaluru, Karnataka, India

Ganesan Venkatasubramanian, MD, PhD

Role: STUDY_CHAIR

Professor at Department of Psychiatry, NIMHANS, Bengaluru, Karnataka, India

Locations

Department of Psychiatry, National Institute of Mental Health And Neuro Sciences (NIMHANS), Bengaluru, Karnataka

Bengaluru, Karnataka, India

Site Status: RECRUITING

Countries

India

Central Contacts

Anushree Bose, PhD

Role: CONTACT

anushree.cp@gmail.com

+91-8026995366

Ganesan Venkatasubramanian, MD, PhD

Role: CONTACT

gvs@nimhans.ac.in

+91-8026995366

Facility Contacts

Anushree Bose, PhD

Role: primary

anushree.cp@gmail.com

+91-80-26995366

Ganesan Venkatasubramanian, MD, PhD

Role: backup

gvs@nimhans.ac.in

+91-80-26995366

Other Identifiers

IA/CPHE/19/1/504591

Identifier Type: -

Identifier Source: org_study_id