Natasza D Orlov1, Derek K Tracy2, Daniel Joyce3, Shinal Patel4, Joanna Rodzinka-Pasko4, Hayley Dolan4, John Hodsoll4, Tracy Collier4, John Rothwell5, Sukhwinder S Shergill3. 1. Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom. Electronic address: natasza.nalesnik@kcl.ac.uk. 2. Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; Oxleas National Health Service (NHS) Trust, London, United Kingdom. 3. Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; South London and Maudsley NHS Trust, London, United Kingdom. 4. Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom. 5. Institute of Neurology, University College London, United Kingdom.
Abstract
BACKGROUND: Schizophrenia is characterized by prominent cognitive deficits, impacting on memory and learning; these are strongly associated with the prefrontal cortex. OBJECTIVE/HYPOTHESIS: To combine two interventions, transcranial direct current stimulation (tDCS) over the prefrontal cortex and cognitive training, to examine change in cognitive performance in patients with schizophrenia. METHODS: A double blind, sham-controlled pilot study of 49 patients with schizophrenia, randomized into real or sham tDCS stimulation groups. Subjects participated in 4 days of cognitive training (days 1, 2, 14, 56) with tDCS applied at day-1 and day-14. The primary outcome measure was change in accuracy on working memory and implicit learning tasks from baseline. The secondary outcome measure was the generalization of learning to non-trained task, indexed by the CogState neuropsychological battery. Data analysis was conducted using multilevel modelling and multiple regressions. RESULTS: 24 participants were randomized to real tDCS and 25 to sham. The working memory task demonstrated a significant mean difference in performance in the tDCS treatment group: at day-2 (b = 0.68, CI 0.14-1.21; p = 0.044) and at day-56 (b = 0.71, 0.16-1.26; p = 0.044). There were no significant effects of tDCS on implicit learning. Trend evidence of generalization onto untrained tasks of attention and vigilance task (b = 0.40, 0.43-0.77; p = 0.058) was found. CONCLUSIONS: This is the first study to show a significant longer-term effect of tDCS on working memory in schizophrenia. Given the current lack of effective therapies for cognitive deficits, tDCS may offer an important novel approach to modulating brain networks to ameliorate cognitive deficits in schizophrenia.
BACKGROUND: Schizophrenia is characterized by prominent cognitive deficits, impacting on memory and learning; these are strongly associated with the prefrontal cortex. OBJECTIVE/HYPOTHESIS: To combine two interventions, transcranial direct current stimulation (tDCS) over the prefrontal cortex and cognitive training, to examine change in cognitive performance in patients with schizophrenia. METHODS: A double blind, sham-controlled pilot study of 49 patients with schizophrenia, randomized into real or sham tDCS stimulation groups. Subjects participated in 4 days of cognitive training (days 1, 2, 14, 56) with tDCS applied at day-1 and day-14. The primary outcome measure was change in accuracy on working memory and implicit learning tasks from baseline. The secondary outcome measure was the generalization of learning to non-trained task, indexed by the CogState neuropsychological battery. Data analysis was conducted using multilevel modelling and multiple regressions. RESULTS: 24 participants were randomized to real tDCS and 25 to sham. The working memory task demonstrated a significant mean difference in performance in the tDCS treatment group: at day-2 (b = 0.68, CI 0.14-1.21; p = 0.044) and at day-56 (b = 0.71, 0.16-1.26; p = 0.044). There were no significant effects of tDCS on implicit learning. Trend evidence of generalization onto untrained tasks of attention and vigilance task (b = 0.40, 0.43-0.77; p = 0.058) was found. CONCLUSIONS: This is the first study to show a significant longer-term effect of tDCS on working memory in schizophrenia. Given the current lack of effective therapies for cognitive deficits, tDCS may offer an important novel approach to modulating brain networks to ameliorate cognitive deficits in schizophrenia.
Authors: Tyler B Grove; Beier Yao; Savanna A Mueller; Merranda McLaughlin; Vicki L Ellingrod; Melvin G McInnis; Stephan F Taylor; Patricia J Deldin; Ivy F Tso Journal: Psychiatry Res Date: 2018-05-07 Impact factor: 3.222
Authors: J S Gomes; A P Trevizol; D V Ducos; A Gadelha; B B Ortiz; A O Fonseca; H T Akiba; C C Azevedo; L S P Guimaraes; P Shiozawa; Q Cordeiro; A Lacerda; A M Dias Journal: Schizophr Res Cogn Date: 2018-02-20