Restoration of Cognitive Function With TDCS and Training in Serious Mental Illness

Development of interventions that can effectively target and remediate the cognitive and functional impairment associated with serious mental illness is a treatment priority. Transcranial direct current stimulation (tDCS) is a safe, non-invasive neuromodulation technique that is capable of stimulating brain activity to facilitate learning. The primary objective of this study is to evaluate the pairing of two therapeutic techniques, cognitive remediation and tDCS, as a cognitively enhancing intervention. This study is designed to test the hypotheses that cognitive remediation paired with tDCS will be more efficacious than cognitive remediation delivered with sham stimulation and that intervention-induced cognitive change will be sustainable.

To examine the incremental benefit of pairing tDCS with cognitive remediation, clinically stable outpatients between the ages of 18-65 who have a diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder will be enrolled in a double-blind, double-baseline, sham-controlled clinical trial. Participants will be randomized in a 1:1 ratio to receive either tDCS or sham stimulation concurrent with working memory focused cognitive remediation. Training will be offered to participants in a small group format. Training will consist of 48 sessions, with 2-3 sessions scheduled in a week. Each training session will last 2 hours. One hour will be spent completing cognitive exercises that require working memory skills on a computer. TDCS or sham stimulation will be offered concurrent with the first 20 minutes of training with a StarStim neuromodulator. One mA of anodal stimulation will be applied to the left dorsal lateral prefrontal cortex and the cathodal electrode will be placed in the contralateral supraorbital position. Upon completion of working memory training, participants will transition to a 45-minute bridging group focus on application of cognitive skills in everyday life. To assess intervention-induced change, working memory, other aspects of cognition, functional capacity, community functioning, and symptom severity will be assessed pre- and post-intervention. Sustainability of intervention-induced change will be assessed with an assessment session 6 weeks post-intervention. Mixed effect, repeated measure ANOVAS will be used to analyze intervention-induced change.


Eligibility Criteria:
Inclusion Criteria:

* Participants are eligible for the study if they have a diagnosis of schizophrenia, schizoaffective disorder, or bipolar I disorder and are clinically stable at the time of enrollment

  * defined as not severely depressed or acutely manic and no hospitalizations or antipsychotic medication changes in the four weeks prior to enrollment

Exclusion Criteria:

* Met criteria for a severe alcohol or substance use disorder in the last 6 months
* Met criteria for a mild alcohol or substance use disorder in the last month
* A history of head injury or neurological disease that has compromised cognitive functioning
* Ability to speak English is not sufficient to understand study procedures
* Diagnosis of learning disability, mental retardation, or pervasive developmental disorder
* Diagnosis of a medical condition that is incompatible with tDCS procedures
* Participant does not demonstrate understanding of study procedures during the consent process
* A documented history of behavioral problems that prevent participation in a group intervention
* Participated in a study of tDCS or cognitive remediation in the previous 12 months