RCT of tDCS Combined With Cognitive Training in Schizophrenia
Condition: Schizophrenia
MeSH terms: Schizophrenia
Study type: Interventional

Summary: 
      Given the superior effects of CT augmented tDCS in healthy subjects, the aim of the current
      study was to examine whether the effect of CT on cognition can be enhanced with concurrent
      anodal tDCS in schizophrenia patients. A double-blinded randomised controlled trial design
      was utilised and cognitive performances were examined at baseline (T0), immediately after the
      intervention (T1) and one month post-intervention (T2). It was hypothesized that concurrent
      CT with tDCS would result in greater and more sustainable cognitive improvement than CT alone
      because of increased susceptibility to neuroplasticity changes of the underlying activated
      network (Bikson et al., 2013; Orlov, O'Daly, et al., 2017). The effects of concurrent CT with
      tDCS were also assessed using blinded assessments of psychotic, negative symptoms, affective
      symptoms, psychosocial functioning, subjective quality of life (QOL) and tolerability in the
      two groups.
    

Detailed description: 
      The current study is a parallel-group, double-blinded, randomised controlled trial that aimed
      to fill the knowledge gap in investigating the effect of five sessions of concurrent
      cognitive training with 'online' tDCS on specific cognitive domains in stable schizophrenia
      patients at two time-points, (i) immediately after the intervention (ii) at one month after
      intervention.

      It was hypothesized that concurrent cognitive training with 'online' tDCS would result in
      greater incremental effective improvements in cognitive domains as compared to the cognitive
      training alone, and the effect would be sustainable at one-month follow-up. The effect of the
      concurrent cognitive training with 'online' tDCS were also assessed using blinded assessments
      of psychotic, negative symptoms, affective symptoms, psychosocial functioning, subjective
      quality of life (QOL) and tolerability in the two groups.

      Participant were randomly allocated to one of the two groups using a predetermined
      randomisation sequence and block randomisation generator (block of 6). Group 1 received
      active tDCS stimulation and CT and will be referred to as the active tDCS + CT group. Group 2
      received sham tDCS and CT and will be referred to as the sham tDCS + CT group. Both groups
      consisted of 23 participants and received five treatment sessions on five consecutive days.

      Stimulation protocol with the corresponding randomisation code was set up by an independent
      psychiatrist.The double-blind administration panel of the SatrStim8 system of tDCS ensured
      effective blinding; both the principal investigator and the participants were blinded to the
      group allocation until the statistical analysis stage. All outcome measures were assessed at
      three time-points (T0, baseline; T1, end-treatment course; and T2, at one-month
      post-intervention).

      Declaration:

      The research protocol fully complies with the Declaration of Helsinki and the guidelines of
      ICH-GCP.
    

Intervention name(s): tDCS; Cognitive Training
Intervention type(s): Device; Behavioral
Intervention description(s): tDCS was applied using the StarStim 8 (NeuroElectrics, Barcelona, Spain). tDCS with strength of two milliamps for 20 minutes was applied based on montage recommended (Hoy et al., 2014). The stimulation electrode was applied according to international EEG system 10-20. The anode was applied at the left dorsolateral prefrontal cortexDLPFC, which was located at F3; the cathode was applied at the right dorsolateral prefrontal cortexDLPFC, which was located at F4. In the tDCS group, the participants received 'ramp-up' of 30 seconds, followed by active stimulation with a steady current of two milliamps for 20 minutes, then 'ramp-down' of 30 seconds. In the sham group, the current was only delivered in the 30-second 'ramp-up' and 30-second 'ramp-down' period.; All participants received the same program of cognitive training in the app 'the Peak' on a hand-held portable iPad (https://www.peak.net/science/). The traditional Chinese version with Cantonese instructions was selected. The progress, the errors, and the sum scores were stored in the personal profile for interactive feedback on adjusting the difficulty level. The participants performed the tasks in pseudorandomized order during each session. Each training session lasted for 20 minutes, concurrent with either active or sham tDCS stimulation.
Other intervention name(s): StarStim 8
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science
Keywords: cognitive training; transcranial direct current stimulation; cognitive intervention; cognitive dysfunction; schizophrenia