ClinicalTrials.gg
CompletedNCT03388554Updated May 1, 2018

The Effects of tDCS on Auditory Hallucination, Insight, Neurocognitive Function and HRV in Patients With Schizophrenia

An interventional study of tDCS in Schizophrenia, Schizoaffective Disorder and Auditory Hallucination, Verbal, sponsored by Tri-Service General Hospital. Completed at 1 site in Taiwan. Open to participants aged 20 Years to 65 Years. Per ClinicalTrials.gov, last updated 2018-05-01.

Sponsored by Tri-Service General Hospital · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Registered 1 year 5 months after the study started (first participant enrolled Jul 2016, registered Dec 2017).
Phase
Not applicable
Study type
Interventional
Enrollment
60
Allocation
Randomized
Ages
20 Years to 65 Years
Sex
All
01

Study summary

The study aimed to investigate whether transcranial direct current stimulation could modify auditory hallucination, insight, neurocognitive function, heart rate variability, psychosocial functioning and quality of life in patients with schizophrenia.

Read the detailed description

Transcranial direct current stimulation (tDCS), a novel, non-invasive and safe neuro-modulating technique, has been developed as a new therapeutic option for neuropsychiatric disorders. It encompasses the induction of a relatively weak constant current flow through the cerebral cortex via scalp electrodes. Dependent on stimulation polarity, this results in a modulation of cortical excitability and spontaneous neural activity. The technique was established in the 1950s and 1960s primarily in animals. In these early studies it was shown that subthreshold DC stimulation increases spontaneous neuronal activity if the anode is placed above or within the cortex, while exposure to cathodal polarity results in reduced activity. This is caused by a subthreshold membrane depolarization by anodal and a hyperpolarization by cathodal stimulation. It was demonstrated in humans that the after-effects of tDCS depend on modifications of NMDA receptor-efficacy. The after-effects of tDCS are blocked by the NMDA receptor antagonist dextromethorphan, and prolonged by the partial NMDA receptor-agonist D-cycloserine. This tDCS polarity-dependent alteration of NMDA receptor function seems to be initiated by the respective membrane potential shift and probably by the accompanying cortical activity modification,because it is prevented by the sodium channel blocker carbamazepine. Intraneuronal calcium concentration also contributes, because calcium channel antagonists eliminate the excitability-enhancing aftereffects of anodal tDCS. Recently, tDCS has been found to improve psychopathological symptoms (auditory hallucination in particular), cognitive deficits and insight of schizophrenia and also strengthen cardiac autonomic function in healthy subjects. Further replication studies are needed.

The study aimed to investigate whether transcranial direct current stimulation could modify auditory hallucination, insight, neurocognitive function, heart rate variability, psychosocial functioning and quality of life in patients with schizophrenia.

Study design: randomized double-blind, sham-controlled study design.

Participants: 60 patients having a diagnosis of schizophrenia or schizoaffective with refractory auditory verbal hallucinations (defined as the persistence of daily auditory verbal hallucinations without remission in spite of antipsychotic medications at an adequate dosage for at least 3 months), aged 20-65 years.

Others: see Arms and Interventions, Eligibility Criteria or Outcome Measures.

02

Conditions studied

  • Schizophrenia
  • Schizoaffective Disorder
  • Auditory Hallucination, Verbal
  • Neurocognitive Dysfunction
  • Autonomic Imbalance
  • Psychosocial Impairment
  • Quality of Life
03

In context

Schizophrenia

3,563 studies on the registry are indexed under Schizophrenia; 491 are open to participants now.

This study's enrollment of 60 is below the median of 71 across 2,944 interventional studies indexed under Schizophrenia.

Browse Schizophrenia studies →

Lead sponsor

Tri-Service General Hospital is the lead sponsor of 108 studies on the registry; 11 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
20 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Patients who met criteria for schizophrenia or schizoaffective disorder were included in the study. All these patients showed auditory verbal hallucinations,which are defined as the persistence of daily auditory verbal hallucinations without remission in spite of antipsychotic medications at an adequate dosage for at least 3 months.

Exclusion criteria

Exclusion Criteria:

  1. Pregnancy or breastfeeding.
  2. Having epilepsy, severe physical illness, any current psychiatric comorbidity or history of substance dependence.
  3. Having for transcranial electrical/magnetic stimulation.
  4. Having intracranial metal foreign bodies.
  5. Having a history of intracranial neoplasms or surgery, or a history of severe head injuries or cerebrovascular diseases.
Terms in these criteria, in plain language(3)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

DSM diagnostic criteria

The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.

Relapsed and refractory

Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Outcomes assessor)
Enrollment
60 participants (actual)

Study arms

  • Active comparator
    Active tDCS

    Direct current (DC) generated by a DC stimulator (Eldith DC stimulator: www. neuroconn.de/dc-stimulator_plus_en/) was bilaterally delivered through a pair of saline-soaked surface sponge electrodes (35 square centimeter). The anode was placed with the middle of the electrode over a point midway between F3 and FP1 (left dorsolateral prefrontal cortex and left prefrontal cortex). The cathode was located over a point midway between T3 and P3 (left temporo-parietal junction). Stimulation was applied at an intensity of 2 mA for 20 min, twice-daily on 5 consecutive weekdays. The twice daily sessions were separated by at least 3 hours. All patients in the active tDCS group were maintained on their antipsychotic medications throughout the study period.

    Device: tDCS

  • Sham comparator
    Sham tDCS

    In sham stimulation, the current was turned on for 30 sec and then ramped down to 0 mA. All patients in the sham tDCS group were maintained on their antipsychotic medications throughout the study period.

    Device: tDCS

Interventions

  • DevicetDCS
06

What researchers measure

Primary outcomes

  1. Changes from baseline scores of Auditory Hallucination Rating Scale (AHRS) at the timepoint immediately after tDCS, at one month and three months after tDCS.

    A clinician-administered rating scale to measure the severity of auditory (verbal) hallucination of the patients with schizophrenia spectrum disorder.

    Time frame: Three months.

Secondary outcomes

  1. Changes from baseline scores of Positive and Negative Syndrome Scale (PANSS) at the timepoint immediately after tDCS, at one month and three months after tDCS.

    A clinician-administered rating scale to measure the severity of psychopathological symptoms of the patients with schizophrenia spectrum disorder.

    Time frame: Three months.

  2. Changes from baseline scores at Personal and Social Performance scale (PSP) at the timepoint immediately after tDCS, at one month and three months after tDCS.

    A clinician-administered rating scale to measure the psychosocial functioning of the patients with schizophrenia spectrum disorder.

    Time frame: Three months.

  3. Changes from baseline results of Digit span (forward and backward)

    A test to measure the capacity of working memory of the patients.

    Time frame: One month.

  4. Changes from baseline results of Finger tapping test

    A neuropsychological test that examines motor functioning, specifically, motor speed and lateralized coordination.

    Time frame: One month.

  5. Changes from baseline results of Continuous Performance (CPT, version 2.0)

    A neuropsychological test that examines the performance of prefrontal-mediated task.

    Time frame: One month.

  6. Changes from baseline results of Wisconsin Card Sorting Test (WCST) at the timepoint immediately after tDCS and at one month after tDCS.

    A neuropsychological test of "set-shifting", i.e. the ability to display flexibility in the face of changing schedules of reinforcement.

    Time frame: One month.

  7. Changes from baseline results of Trail Making Test (TMT) at the timepoint immediately after tDCS and at one month after tDCS.

    A neuropsychological test of visual attention and task switching.

    Time frame: One month.

  8. Changes from baseline results of Tower of London test at the timepoint immediately after tDCS and at one month after tDCS.

    A neuropsychological test for the assessment of executive functioning specifically to detect deficits in planning, which may occur due to a variety of medical and neuropsychiatric conditions.

    Time frame: One month.

  9. Changes from baseline heart rate variability (HRV) at the timepoint immediately after tDCS and at one month after tDCS.

    An index of autonomic functioning.

    Time frame: One month.

  10. Changes from baseline scores of the brief version of questionnaire of The World Health Organization Quality of Life (WHOQOL-BREF Taiwan version) at the timepoint immediately after tDCS and at one month after tDCS.

    A self-reported questionnaire to measure quality of life of the patients.

    Time frame: One month.

  11. Changes from baseline scores of self-reported version of the graphic Personal and Social Performance scale (SRG-PSP) at the timepoint immediately after tDCS and at one month after tDCS.

    A self-reported graphic questionnaire to measure psychosocial functioning of the patients.

    Time frame: One month.

  12. Changes from baseline scores of the abbreviated version of the Scale to Assess Unawareness in Mental Disorder in schizophrenia (SUMD) at the timepoint immediately after tDCS, at one month and three months after tDCS.

    An expert-rating scale based on a patient interview to measure the insight of the patient.

    Time frame: Three months.

  13. Changes from baseline scores of the Taiwanese version of the Beck Cognitive Insight Scale (BCIS) at the timepoint immediately after tDCS and at one month after tDCS.

    Translated BCIS has two subscales including reflective attitude (R, 9 items, score range 9-36) and certain attitude (C, 6 items, score range 6-24) subscales. The higher score in R subscale indicates higher self-reflectiveness while the higher score in C subscale indicates higher self-certainty. Thus, a composite index (R-C, reflective attitude minus certain attitude, score range 3-30) of the translated BCIS represents the measurement of cogntive insight . The higher score of R-C index indicates higher cognitive insight.

    Time frame: One month.

  14. Changes from baseline scores of the Taiwanese version of the Self- Appraisal of Illness Questionnaire (SAIQ) at the timepoint immediately after tDCS and at one month after tDCS.

    This scale is a self-report instrument composed of 17 items on which participants are asked to rate the extent to which they agree with each statement using a four-point Likert scale, ranging from 0, ''do not agree at all'', to 3, ''agree completely'', which varies according to the statement or questions content. SAIQ has three subscales including worry, need for treatment, and presence/outcome of illness subscales. The scores for the three subscales were summed to create a total SAIQ score (range 17-68), which is intended to represent a broad measure of insight. Lower SAIQ total scores indicate less awareness of one's psychiatric illness.

    Time frame: One month.

07

Study locations

1 site
  • Tri-service general hospital
    Taipei, 114, Taiwan
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Jul 2016 to primary completion in Mar 2018, 20 months.

Of 753 non-industry interventional studies with no phase under Schizophrenia, half reached primary completion within 33 months of starting (the median), counting those still running; a quarter within 17 and three quarters within 56. This study's 20 months is below that.

Counting every sponsor, half of 766 studies reached it within 32 months; a quarter within 16 and three quarters within 56.

How these figures are worked out, and which studies are left out of them.

Registered
Dec 24, 2017
First posted
Jan 3, 2018
StartActual
Jul 2016
Primary completionActual
Mar 2, 2018
CompletionActual
Mar 2, 2018
Last update
May 1, 2018
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on May 1, 2018, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT03388554
Responsible party
Hsin-An Chang, MD (Head of Laboratory of Psychophysiology, Department of Psychiatry, Principal Investigator, Attending Psychiatrist, Assistant Professor, Tri-Service General Hospital) — Principal investigator
First posted
Jan 3, 2018
Start date
Jul 2016
Primary completion
Mar 2, 2018
Completion
Mar 2, 2018
Last update
May 1, 2018

Study contacts

Hsin-An Chang, M.D.
principal investigator · Tri-Service General Hospital, National Defense Medical Center

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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