Non-invasive Brain Stimulation Using Tdcs of the Third (of Many) Visual Pathways

Inclusion Criteria: 1. Male or female subject, age 18-55 2. Competent and willing to sign informed consent 3. No more than moderately ill 4. SCID DSM-5 diagnosis of Sz/SzAff 5. WAIS IQ \>70 6. Does not meet current criteria for DSM-5 defined substance abuse or dependence or have a history of diagnosis within past 6 months 7. On medication within clinically approved range 8. Does not meet criteria for another DSM-5 disorder other than those judged to be minor (e.g. simple phobia) Exclusion Criteria: 1. Significant neurological illness or history of significant head trauma 2. Unstable physical illness or significant auditory/visual deficits that might interfer 3. Contraindication to MRI (e.g. metal implants, claustrophobia, pregnancy) 4. Contraindications to tDCS including metal implant, pacemaker, history of seizure, traumatic brain injury or stroke 5. Significant risk for suicide 6. Has a history of an illness, disease, condition injury, or disability which, in the opinion of the principal investigator, may interfere with the completion of all study requirements per protocol, impact the quality of the data, or the validity of the study results, including unstable physical illness, significant neurological illness, significant head trauma 7. Moderate or greater DSM-5 current substance use disorder, defined based on the presence of 4 or more of 11 substance use criteria within the past 12 months. In addition, individuals for whom substance use leads to not being able to perform work, home or school activities