Working memory performance with online-tDCS in schizophrenia: A randomized, double-blinded, sham-controlled, partial cross-over proof-of-concept study.
Asian J Psychiatr
; 50: 101946, 2020 Apr.
Article
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| MEDLINE
| ID: mdl-32087502
ABSTRACT
Combining cognitive retraining with transcranial direct current stimulation (tDCS) has been hypothesized to improve cognitive deficits in schizophrenia. The effect of combining a neuropsychological/psychophysiological task with tDCS, called "online-tDCS" for cognitive enhancement in schizophrenia is not rigorously assessed. In this proof-of-concept study, we aimed at evaluating the effect of a single session online-tDCS on working memory(WM) and its transferability to other cognitive functions. Numerical n-back(NNB), digit symbol substitution test(DSST), emotional matching and labelling test(E-MALT), and anti-saccade eye movement beeforefore and after 20 min tDCS (anode left dorsolateral prefrontal cortex and cathode left temporoparietal junction) applied during Sternberg's task(WM-task) were assessed. Twenty-three schizophrenia patients with cognitive deficits were randomized to receive either online-tDCS or offline-tDCS (without simultaneous Sternberg's task) sessions. All patients received one session each of active and sham tDCS in a randomized counterbalanced double-blind cross-over design. RMANOVA revealed a significant interaction effect between tDCS type (Online/Offline) x activeness (active/sham) of tDCS; the reaction time during 2-back performance in the NNB test improved in online-sham (F = 5.23, p < 0.038) but not online-active tDCS session. No significant changes were noted in DSST, E-MALT, and anti-saccade performance. Improved performance after online-sham tDCS suggests that performing the Sternberg's task enhanced 2-back performance. The counterintuitive observation was noted with respect to the non-enhancement of WM performance on combining the task to tDCS. Aberrant plasticity in schizophrenia might attain a transitional ceiling that would have resulted in restriction of enhancement on combining the two plasticity modulators. The transferability of improvement to other cognitive domains could not be ascertained.
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Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Esquizofrenia
/
Estimulación Transcraneal de Corriente Directa
/
Memoria a Corto Plazo
Tipo de estudio:
Clinical_trials
Límite:
Adult
/
Humans
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Male
Idioma:
En
Revista:
Asian J Psychiatr
Año:
2020
Tipo del documento:
Article