Improving Cognition in Schizophrenia Using tDCS

This study will examine the benefits of transcranial direct current stimulation (tDCS), a new tool that is being developed as a safe and non-invasive neurostimulation method, for improving neurocognitive and social cognitive functions in schizophrenia. This procedure is non-invasive and painless and it results in increase or decrease of spontaneous neuronal firing in the brain. Its safety and beneficial effect on cognition has been demonstrated in healthy individuals and several clinical populations. In this pilot study, the investigators will examine the effect of tDCS on cognitive functions in 40 individuals with schizophrenia. Each participant will arrive for three visits, with approximately one week between each visit. During the first visit, participants will be interviewed about their psychiatric symptoms, personal life experiences, and emotional well being by a specially-trained interviewer. On each of the three visits, participants will receive one of three stimulations: a type of tDCS designed to increase neuronal firing, an alternative form of tDCS designed to decrease neuronal firing, and a sham tDCS (stimulation with no current). Immediately following the stimulation, participants will be asked to complete measures of mental abilities, including tests presented on a computer screen and paper-and-pencil tests. During each visit, participants will also undergo a standard measure of brain activity (EEG) while listening to tones. The first visit will last approximately five hours, and the other two visits will last approximately four hours each. The project will take approximately two years to complete.