Transcranial Direct Current Stimulation and Cognitive Remediation Therapy for Psychosis

Not Applicable

Completed

Conditions: Psychosis

Interventions: Device: tDCS

Registration Number: NCT02085421

Lead Sponsor: University of Minnesota

Brief Summary: The proposed pilot study is a randomized controlled study to assess effectiveness of transcranial direct current stimulation (tDCS) to enhance cognitive remediation therapy in patients with psychotic disorders. tDCS. Patients will be randomized into two arms: active tDCS vs. sham tDCS. The active tDCS will be applied at a current of 1-2 mA (milliamperes) via two saline soaked electrode sponges (3 cm x 4.5 cm) applied to the side of the head. The investigators hypothesis is that the use of tDCS will enhance the improvement seen with cognitive remediation therapy.

Detailed Description: The proposed pilot study is a randomized controlled study to assess effectiveness of tDCS to enhance cognitive remediation therapy in patients with psychotic disorders. All patients will participate in cognitive remediation therapy (CRT). After initial consent form has been signed, all participants will undergo various neurocognitive and psychological assessments including the Brief Assessment of Cognition in Schizophrenia (BACS), an EEG, and several other tasks/assessments. Participants will then complete 2-4 CRT sessions per week, each lasting approximately one hour, for a total of 10 sessions. The CRT will use a commercially available PositScience software package. Each CRT session involves an in-session assessment of skill acquisition, as collected by commercially available CRT software.

Patients will be randomized into two arms: active tDCS vs. sham tDCS. The tDCS will be applied at a current of 1-2mA via two saline soaked electrode sponges (3 cm x 4.5 cm) each CRT session. The anode will be placed over left DLPFC (dorsolateral prefrontal cortex) at F3, according to the 10-20 international system for EEG electrode placement. The cathode will be placed over the contralateral supraorbital area (Fp2). This placement is consistent with previous protocols targeting working memory. Both active and sham conditions will have identical electrode placement.

After electrodes have been placed, the participants will be instructed to log into CRT software using a unique patient identifier. Once logged in to CRT software they will be instructed to begin the session.

The tDCS will be applied at a current of 1-2mA via two saline soaked electrode sponges (3 cm x 4.5 cm) for the first 20 minutes of each CRT session in the active condition. In the sham condition, tDCS will be ramped up to 1-2 mA via two saline soaked electrode sponges (3 cm x 4.5 cm) over the first 30 seconds of each CRT session and then turned off.

Participants will complete the hour long CRT session. The software program instructs the patient when the end of the session has been reached.

At the completion of the 10 sessions of CRT, both active and sham tDCS patients will repeat the the same assessments from the beginning, including the BACS, another EEG, and several other tasks/assessments. Patients will also be asked to return for a 1-month follow-up where most of the same tasks/assessments are completed.

The consent and baseline assessments take about 8 hours in total and can be split up into 2-4 appointments. Each of the 10 training sessions lasts approximately 1 hour for a total of 10 hours of training. The post-training assessments take about 6 hours and can be split up into 2-3 appointments. The 1-month follow-up takes approxmately 3.5 hours and can be completed in 1-2 appointments. The total time commitment for this study is approximately 28-32 hours.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 33

Inclusion Criteria

Meet diagnostic criteria for schizophrenia or schizoaffective disorder
Are age 18-64
Fluent in written and spoken English
Have an outpatient status of at least 1 month prior to participation
Has been on a stable dose of psychiatric medication for at least one month prior to participation

Exclusion Criteria

History of seizures or epilepsy
Metallic cranial plates, screws, or implanted devices
History of craniotomy
History of stroke
History of eczema on scalp
Pre-existing sores or lesions at sites of tDCS electrode placement
Non removable facial piercings
Current or possibility of current pregnancy
Has received a clinically meaningful dose of a targeted cognitive training intervention in the last 12 months

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Active tDCS	tDCS	The active tDCS will be applied at a current of 1-2mA via two saline soaked electrode sponges (3 cm x 4.5 cm) for the first 20 minutes of each CRT session in the active condition.
Sham tDCS	tDCS	In the sham condition, tDCS will be ramped up to 1-2 mA via two saline soaked electrode sponges (3 cm x 4.5 cm) over the first 30 seconds of each CRT session and then turned off.

Primary Outcome Measures

Name	Time	Method
Change in Brief Assessment of Cognition in Schizophrenia (BACS) From Baseline to Post-Training	Baseline, 3-5 weeks	Clinician-administered neurocognitive battery that assesses the aspects of cognition found to be most impaired and most strongly correlated with outcome in patients with schizophrenia. Brief Assessment of Cognition in Schizophrenia (BACS) - post training composite z-score range Arm 1 = -2.46 - 2.24 range Arm 2 = -7.67 - 0.83 Higher scores represent better cognitive performance. The BAC APP composite z-score is calculated as the sum of the subscale z-scores (i.e., verbal memory, digit sequencing, verbal fluency, symbol coding, and tower of london), adjusted by participant age and sex. The primary outcome measure from the BACS is a composite z score, with 0 representing the population mean, normed by age and gender.
Change in the Virtual Reality Functional Capacity Assessment Tool (VRFCAT) From Baseline to Post-Training	Baseline, 3-5 weeks	The VRFCAT is a performance-based functional capacity measure and the 'total recipes accessed' variable represents one component of the full measure. Using a realistic virtual reality environment, the VRFCAT assesses a subject's ability to complete instrumental activities associated with a shopping trip. This provides an estimate of performance on everyday functional tasks. The summary measures include: total time (seconds), total errors, total progressions, total bus schedule checks, total recipe checks. There is no combined total score for this Tool. The minimum number of recipe checks is 0 and there is no maximum number of recipe checks for this task. A higher score on the summary measure 'total recipe checks' indicates worse performance. This means that the higher the number of times a subject consults the reference materials (i.e., recipe), the worse the performance. Based o
Change in the D-prime Score of the N-Back Working Memory Test From Baseline to Post-Training	Baseline, 3-5 weeks	N-back testing is a performance task used to assess working memory. In this task, pairs of numbers are presented on a computer screen, and participant are instructed to press a button whenever the pair of numbers corresponds to the pair of numbers presented two trials before (2-back). Number of hits and number of false alarms are used to calculate d-prime, the primary outcome. Depending on the number of trials completed, the range of d-prime is expected to be from -4.46 (0 hits, 80 FA) to +4.46 (20 hits, 0 FA), based on the literature. In our study, hits ranged from 3-56 and false alarms ranged from 1-146, therefore d-prime ranged from -0.42-4.02 in the full sample for the 2-back condition. A lower score on d-prime indicates worse performance.

Secondary Outcome Measures

Name	Time	Method
N-Back - Post Training 2-back Number of Hits Provided Here	3-5 weeks	reflects the number of correct responses and the unit is the number of trials. Number of hits and number of false alarms are used to calculate d-prime, the primary outcome.
N-Back - Post Training 2-back Number of False Alarms Provided Here	3-5weeks	reflects the number of times the participant incorrectly indicates that there is a match (when there is not) and the unit is the number of trials. Number of hits and number of false alarms are used to calculate d-prime, the primary outcome.