Stimulating the Brain to Improve Self-Awareness

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.

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)