title: Effects of transcranial direct current stimulation (tDCS) on cognition, symptoms, and smoking in schizophrenia: A randomized controlled study.
abstract: Schizophrenia is characterized by cognitive deficits which persist after acute symptoms have been treated or resolved. Transcranial direct current stimulation (tDCS) has been reported to improve cognition and reduce smoking craving in healthy subjects but has not been as carefully evaluated in a randomized controlled study for these effects in schizophrenia. We conducted a randomized double-blind, sham-controlled study of the effects of 5 sessions of tDCS (2 milliamps for 20minutes) on cognition, psychiatric symptoms, and smoking and cigarette craving in 37 outpatients with schizophrenia or schizoaffective disorder who were current smokers. Thirty subjects provided evaluable data on the MATRICS Consensus Cognitive Battery (MCCB), with the primary outcome measure, the MCCB Composite score. Active compared to sham tDCS subjects showed significant improvements after the fifth tDCS session in MCCB Composite score (p=0.008) and on the MCCB Working Memory (p=0.002) and Attention-Vigilance (p=0.027) domain scores, with large effect sizes. MCCB Composite and Working Memory domain scores remained significant at Benjamini-Hochberg corrected significance levels (α=0.05). There were no statistically significant effects on secondary outcome measures of psychiatric symptoms (PANSS scores), hallucinations, cigarette craving, or cigarettes smoked. The positive effects of tDCS on cognitive performance suggest a potential efficacious treatment for cognitive deficits in partially recovered chronic schizophrenia outpatients that should be further investigated.
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states; Department of Psychiatry NYU Langone Medical Center, United States. Electronic address: rsmith@nki.rfmh.org.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Smith
authors.affiliation: Staten Island University Hospital, Staten Island, New York, United States. Electronic address: boules2@hotmail.com.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Boules
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states. Electronic address: Smattiuz@nki.rfmh.org.
authors.forename: Sanela
authors.initials: S
authors.lastname: Mattiuz
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states. Electronic address: myoussef@nki.rfmh.org.
authors.forename: Mary
authors.initials: M
authors.lastname: Youssef
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states. Electronic address: rtobe@nki.rfmh.org.
authors.forename: Russell H
authors.initials: RH
authors.lastname: Tobe
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states. Electronic address: Sershen@nki.rfmh.org.
authors.forename: Henry
authors.initials: H
authors.lastname: Sershen
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states. Electronic address: Lajtha@NKI.RFMH.ORG.
authors.forename: Abel
authors.initials: A
authors.lastname: Lajtha
authors.affiliation: Nathan S. Kline institute for Psychiatric Research, Orangeburg, New York, United states. Electronic address: Nolan@nki.rfmh.org.
authors.forename: Karen
authors.initials: K
authors.lastname: Nolan
authors.affiliation: Psychiatry Clinic, The Haim Sheba Medical Center, Affiliated to the Tel - Aviv University Sackler School of Medicine TEL-HASHOMER 52621, Israel. Electronic address: amiazr@gmail.com.
authors.forename: Revital
authors.initials: R
authors.lastname: Amiaz
authors.affiliation: University of Illinois College of Medicine Psychiatric Institute, Chicago, Illinois, United States. Electronic address: jmdavis@psych.uic.edu.
authors.forename: John M
authors.initials: JM
authors.lastname: Davis
mesh_terms: D000328:Adult; D003071:Cognition; D066249:Craving; D004311:Double-Blind Method; D006212:Hallucinations / Q000628:therapy; D049690:History, Ancient; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011581:Psychological Tests; D011618:Psychotic Disorders / Q000523:psychology / Q000628:therapy*; D012559:Schizophrenia / Q000628:therapy*; D012565:Schizophrenic Psychology; D012907:Smoking / Q000523:psychology / Q000628:therapy*; D065908:Transcranial Direct Current Stimulation / Q000009:adverse effects / Q000379:methods; D016896:Treatment Outcome
keywords: Cognition; Psychiatric symptoms; Schizophrenia; Smoking; Working memory; tDCS