Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation
technique increasingly used to modulate neural activity in the living brain. In order
to establish the neurophysiological, cognitive or clinical effects of tDCS, most studies
compare the effects of active tDCS to those observed with a sham tDCS intervention.
In most cases, sham tDCS consists in delivering an active stimulation for a few seconds
to mimic the sensations observed with active tDCS and keep participants blind to the
intervention. However, to date, sham-controlled tDCS studies yield inconsistent results,
which might arise in part from sham inconsistencies. Indeed, a multiplicity of sham
stimulation protocols is being used in the tDCS research field and might have different
biological effects beyond the intended transient sensations. Here, we seek to enlighten
the scientific community to this possible confounding factor in order to increase
reproducibility of neurophysiological, cognitive and clinical tDCS studies.
Keywords
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Article Info
Publication History
Published online: January 02, 2019
Accepted:
December 29,
2018
Received in revised form:
December 20,
2018
Received:
September 10,
2018
Identification
Copyright
© 2019 Elsevier Inc. All rights reserved.
