transcranial direct current stimulation and cognitive remediation therapy for psychosis

Conditions: Psychosis

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.

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.

Eligibility criteria:
inclusion criteria: 1. meet diagnostic criteria for schizophrenia or schizoaffective disorder 2. are age 18-64 3. fluent in written and spoken english 4. have an outpatient status of at least 1 month prior to participation 5. has been on a stable dose of psychiatric medication for at least one month prior to participation exclusion criteria: 1. history of seizures or epilepsy 2. metallic cranial plates, screws, or implanted devices 3. history of craniotomy 4. history of stroke 5. history of eczema on scalp 6. pre-existing sores or lesions at sites of tdcs electrode placement 7. non removable facial piercings 8. current or possibility of current pregnancy 9. has received a clinically meaningful dose of a targeted cognitive training intervention in the last 12 months

Keywords: tdcs, neuromodulation, crt, psychosis, schizophrenia