Effects of Transcranial Direct Current Stimulation (tDCS) on Persistent Auditory Verbal Hallucinations in Schizophrenia

Auditory Hallucination, Verbal Clinical Trial

Official title:

The Neural, Behavioural, and Cognitive Outcomes of Transcranial Direct Current Stimulation (tDCS) for Persistent Auditory Verbal Hallucinations in Schizophrenia

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT04222582
• Other study ID #: 2017020
• Status: Recruiting
• Phase: N/A
• Start date: January 1, 2019
• Est. completion date: January 2021

Study information

• Verified date: January 2020
• Source: University of Ottawa
• Contact: Bronwen Schryver, B.Sc.
• Phone: 613 722 6521
• Email: bronwen.schryver[@]theroyal.ca
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Many individuals with schizophrenia struggle with auditory verbal hallucinations (AVHs). In some cases, these AVHs can be resistant to medication treatment. Previous research has found that transcranial direct current stimulation (tDCS) can be helpful in treating symptoms in individuals with other psychiatric disorders, such as depression. This study will assess if tDCS is effective in treating AVHs in individuals with schizophrenia. tDCS is a non-invasive form of brain stimulation which uses a weak current to temporarily excite or inhibit underlying cortical regions with small electrodes placed on the scalp. tDCS has been found to improve mental processes, including attention and memory function. In addition to examining the effect of tDCS on AVHs, this study will assess the effects of tDCS on mood as well as brain electrical activity with electroencephalogram (EEG) recordings. As an additional component, participants will be invited to participate in neuroimaging. Using magnetic resonance imaging (MRI), brain activity and structure will be examined before and after tDCS. tDCS will be administered twice daily for 5 consecutive days for a total of 10 sessions. These study findings will contribute to the understanding of the impact of tDCS on AVHs, and will also increase knowledge of sound and memory/cognitive processing in individuals with schizophrenia.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 84
• Est. completion date: January 2021
• Est. primary completion date: January 2021
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

Patients - Inclusion Criteria:

• Primary diagnosis of schizophrenia or schizoaffective disorder

• Clinically stable (discretion of psychiatrist)

• Consistent history of AVHs over the course of illness

• >3 AVHs per week

• Positive and Negative Syndrome Scale (PANSS) score of >3

• Primary medications limited to one of the atypical antipsychotics (medications stabilized for 4 weeks prior to enrollment)

Patients - Exclusion Criteria:

• Experiencing an acute psychotic episode

• Current drug/alcohol dependence

• Significant medical illness & mental retardation/learning disability

• Extra-pyramidal symptoms resulting in disordered movement

• Abnormal audiometric assessment (thresholds for pure tones >25 dB)

• History of significant neurological issues & head injuries/concussions resulting in loss of consciousness for >5 minutes

Healthy Controls - Inclusion Criteria:

• In good physical health

• No history of serious mental health issues

Healthy Controls - Exclusion Criteria:

• Personal history of psychiatric disorder

• Family history of schizophrenia in first degree relatives & history of mental health issues in first degree relatives that required extensive treatment or hospitalization

• Current/history of substance abuse

• Significant medical illness

• Extra-pyramidal symptoms resulting in movement disorder

• Abnormal audiometric assessment (thresholds for pure tones >25 dB)

• Significant neurological issues & head injuries/concussions resulting in loss of consciousness for >5 minutes

Related Conditions & MeSH terms

• Auditory Hallucination, Verbal
• Hallucinations
• Schizophrenia

Intervention

Device:
• Transcranial direct current stimulation (tDCS)
Transcranial direct current stimulation (tDCS) is a non-invasive form of brain stimulation which uses a weak current (2mA direct current) to temporarily excite or inhibit underlying brain regions with small electrodes placed on the scalp.

Locations

Country	Name	City	State
Canada	Royal Ottawa Mental Health Centre	Ottawa	Ontario

Sponsors (2)

Lead Sponsor	Collaborator
University of Ottawa	The Royal Ottawa Mental Health Centre

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in auditory hallucination severity measured by the Psychotic Symptom Rating Scale (PSYRATS)	The PSYRATS is a multidimensional measure of auditory hallucinations, including 11 items rated on five-point (0-4) scales (total score range 0-44). Symptoms are rated over the last week, with higher scores reflecting more severe symptoms. The dimensions assessed are frequency, duration, location, loudness, beliefs about origin, negative content, intensity of negative content, amount of distress, intensity of distress, disruption of life and control.	Baseline, after 2nd tDCS session on days 1, 3, and 5, and follow-up (within a week of completing tDCS)
Secondary	Change in Voice Power Differential Scale (VPDS) Scores	The Voice Power Differential Scale (VPDS) is a 7-item scale used to measure the perceived power differences between the voice and the voice hearer. Each item is rated on a five-point scale (1-5), with higher scores indicating greater power differential in favour of the voices, with total scores ranging from 7-35.	3 weeks (baseline to follow-up)
Secondary	Change in Beliefs about Voices Questionnaire-Revised (BAVQ-R) Scores	The BAVQ-R is a 35-item questionnaire assessing people's beliefs about auditory hallucinations, and their emotional and behavioural reactions to them. All responses are rated on a 4-point scale: disagree (0); unsure (1); agree slightly (2); agree strongly (3), the measure thus assesses degree of endorsement of items. The scale consists of five subscales: malevolence (score range 0-18), benevolence (0-18), omnipotence (0-18), resistance (0-27), and engagement (0-24).	3 weeks (baseline to follow-up)
Secondary	Change in Voices Acceptance and Action Scale (VAAS) Scores	The VAAS was developed to assess acceptance-based or action-based beliefs in response to auditory verbal hallucinations, in general and specifically to command hallucinations. This 31-item scale is divided into section A (i.e., 12 item stand-alone scale for general auditory hallucinations) and section B, referring specifically to command hallucinations. The participant is asked to rate their opinion from 1 'Strongly Disagree' to 5 'Strongly Agree', with higher scores meaning higher levels of acceptance and perception of acting according to one's valued life directions. Section A scores can range from 12-60, while section B scores can range from 19-95.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - Resting-State Alpha Power	Changes in resting-state EEG power in alpha band. Resting-state recordings completed in both eyes-closed and eyes-open conditions, 5 minutes each.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - Resting-State Beta Power	Changes in resting-state EEG power in beta band. Resting-state recordings completed in both eyes-closed and eyes-open conditions, 5 minutes each.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - Resting-State Delta Power	Changes in resting-state EEG power in delta band. Resting-state recordings completed in both eyes-closed and eyes-open conditions, 5 minutes each.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - Resting-State Theta Power	Changes in resting-state EEG power in theta band. Resting-state recordings completed in both eyes-closed and eyes-open conditions, 5 minutes each.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - Resting-State Gamma Power	Changes in resting-state EEG power in gamma band. Resting-state recordings completed in both eyes-closed and eyes-open conditions, 5 minutes each.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - Mismatch Negativity (MMN)	Change in MMN peak amplitudes and latencies to non-speech (tonal) deviants and speech (syllabic) deviants during the multi-feature optimal MMN paradigm.	3 weeks (baseline to follow-up)
Secondary	Change in Electroencephalography (EEG) - P50	Change in T/C ratio (testing stimulus/conditioning stimulus) during paired click test.; Change in T/C difference (testing stimulus - conditioning stimulus) during paired click test	3 weeks (baseline to follow-up)
Secondary	Change in Brain Functional Magnetic Resonance Imaging (fMRI) - Resting-State	Changes in resting-state activity and connectivity within and between the auditory cortex and select regions of the default-mode network.	3 weeks (baseline to follow-up)
Secondary	Change in Brain Functional Magnetic Resonance Imaging (fMRI) - Mismatch Negativity (tonal)	Changes in task-related activity and connectivity within and between the auditory cortex and select regions of the default-mode network .	3 weeks (baseline to follow-up)
Secondary	Change in Brain Magnetic Resonance Spectroscopy (MRS)	Changes in glutamate/glutamine (Glu/Gln) concentrations in the auditory cortex.	3 weeks (baseline to follow-up)
Secondary	Change in Cambridge Neuropsychological Test Automated Battery (CANTAB) Schizophrenia Battery	Changes in cognitive functioning abilities in core domains often affected in psychosis.	3 weeks (baseline to follow-up)
Secondary	Change in Social Cognition - Social Attribution Task	Changes in social cognition/social inference abilities measured by a computerized social attribution task.	3 weeks (baseline to follow-up)