Stimulating the Brain to Improve Self-Awareness

This study investigates whether Introspective Accuracy (IA) can be improved in individuals with schizophrenia by stimulating the brain via transcranial Direct Current Stimulation (tDCS).

Study Overview

• Status: Completed
• Conditions: Schizophrenia; Schizoaffective Disorder
• Intervention / Treatment: Device: active anodal tDCS; Device: sham tDCS

Detailed Description

Self-awareness is markedly impaired in severe mental illness including schizophrenia and schizoaffective disorder. This impairment spans awareness of symptoms as well as deficits in the estimation of abilities and capabilities, which we refer to as introspective accuracy (IA). Recent work has provided evidence of IA deficits in schizophrenia spectrum disorders, specifically in the abilities to retrospectively judge everyday functioning and neurocognitive impairment, as well as the ability to make correct real-time judgments of performance on neurocognitive tests.

Transcranial Direct Current Stimulation (tDCS) is a form of noninvasive neurostimulation which has been proposed as a therapeutic procedure in numerous psychiatric disorders. TDCS in healthy adults has been demonstrated to improve cognitive and memory performance, and in schizophrenia, tDCS has been found to improve emotion recognition ability. TDCS thus appears to be a promising therapeutic technique that may be useful for improving IA. This study will compare IA performance in individuals with schizophrenia across two conditions: active anodal tDCS and sham tDCS.

• Study Type: Interventional
• Enrollment (Actual): 41
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Texas
    • Richardson, Texas, United States, 75080
      • The Unversity of Texas at Dallas

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 55 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age: 18-55
• DSM-IV-TR or DSM-5 diagnosis of schizophrenia or schizoaffective disorder and clinically stable (i.e., no hospitalizations) for at least 8 weeks and on a stable medication regimen for at least 6 weeks with no dose changes for a minimum of 2 weeks

Exclusion Criteria:

• Presence or history of pervasive developmental disorder (e.g., autism) or mental retardation (defined as IQ <70) by DSM-IV criteria
• Presence or history of medical, cardiac, or neurological disorders that may affect brain function (e.g., cardiac disease, endocrine disorders, renal disease, pulmonary disease, history of seizures or head trauma with unconsciousness for a period of 15 minutes or greater or CNS tumors)
• Presence of sensory limitation including visual (e.g., blindness, glaucoma, vision uncorrectable to 20/40) or hearing (e.g. hearing loss) impairments that interfere with assessment
• Not proficient in English
• Presence of substance abuse in the past one month
• Presence of substance dependence not in remission for the past six months
• Contraindications for tDCS (e.g., pregnancy or implanted devices such as pace maker)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Active anodal tDCS first, then Sham tDCS; Active anodal tDCS (20 minutes) followed by behavioral testing; Washout (1 week); sham stimulation (20 minutes) followed by behavioral testing Intervention: Device: active anodal tDCS and sham tDCS	Device: active anodal tDCS; active anodal tDCS with behavioral tasks to assess IA; Device: sham tDCS; sham tDCS with behavioral tasks to assess IA
Sham Comparator: Sham tDCS first, then Active anodal tDCS; Sham tDCS (20 minutes) followed by behavioral testing; Washout (1 week); Active anodal tDCS (20 minutes) followed by behavioral testing Intervention: Device: sham tDCS and sham tDCS	Device: active anodal tDCS; active anodal tDCS with behavioral tasks to assess IA; Device: sham tDCS; sham tDCS with behavioral tasks to assess IA

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Neurocognitive Introspective Accuracy for Active vs. Sham Stimulation	Neurocognitive Introspective Accuracy (IA) was assessed with the Wisconsin Card Sorting Task after both Active and Sham stimulation. The area under a type 2 ROC (receiver operating characteristic) curve was used to index IA. Values range from .5-1, with higher values indicating better IA.	Assessment will be completed 30 minutes after completion of the active/sham stimulation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Social Cognitive Introspective Accuracy for Active vs. Sham Stimulation	Social Cognitive Introspective Accuracy assessed with the Penn Emotion Recognition Task (ER40) after both Active and Sham stimulation. The area under a type 2 ROC (receiver operating characteristic) curve was used to index IA. Values range from .5-1, with higher values indicating better IA.	Assessment will be completed 30 minutes after completion of the active/sham stimulation

Collaborators and Investigators

• Sponsor: The University of Texas at Dallas

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2017
• Primary Completion (Actual): December 1, 2019
• Study Completion (Actual): December 1, 2019

Study Registration Dates

• First Submitted: December 7, 2017
• First Submitted That Met QC Criteria: December 11, 2017
• First Posted (Actual): December 12, 2017

Study Record Updates

• Last Update Posted (Actual): March 22, 2023
• Last Update Submitted That Met QC Criteria: March 20, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Schizophrenia Spectrum and Other Psychotic Disorders; Schizophrenia; Psychotic Disorders
• Other Study ID Numbers: 17-127

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes