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Examining the Interactions Between Expectations and tDCS Effects on Motor and Cognitive Performance.
Sheida Rabipour1, Petar Sefik Vidjen1, Anthony Remaud2
1School of Psychology, University of Ottawa, Ottawa, ON, Canada.
Frontiers in Neuroscience
|January 23, 2019
Summary
This study found that expectations did not influence the behavioral outcomes of transcranial direct current stimulation (tDCS). Further research is needed to understand the effectiveness of tDCS and its potential placebo effects.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Motor Control
Background:
- The effectiveness of transcranial direct current stimulation (tDCS) is debated, with limited research on expectancy effects.
- Placebo-like effects, influenced by expectations, may modulate tDCS response.
Purpose of the Study:
- To investigate whether participant expectations influence behavioral outcomes in a tDCS intervention.
- To examine the impact of expectation priming and tDCS on motor and cognitive performance.
Main Methods:
- 121 young adults underwent a sham-controlled anodal tDCS study with self-replication.
- Expectations were assessed at baseline, after priming (High/Low), and post-tDCS.
- Motor dexterity (Grooved Pegboard Test) and cognitive tasks (choice reaction time) were performed pre- and post-stimulation.
Main Results:
- Participant expectations varied and were influenced by priming but decreased post-intervention.
- No significant effects of tDCS or expectations were observed on motor or cognitive performance measures.
- Subjective experiences did not differ based on expectation or stimulation conditions.
Conclusions:
- Current findings suggest no clear impact of tDCS or expectations on the measured behavioral outcomes.
- Further research is necessary to elucidate the effects of tDCS and potential placebo mechanisms.
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