About Sham and Double-blind experiments

In tCS, Sham refers to creating an experience for the subject akin to real stimulation, without actually applying significant currents. The subject believes he/she is being stimulated normally, but there should not be any real effects. The goal is to control for placebo effects in treatment. Whether you are doing a doble or single-blind experiment, stimulation sham mode is needed to control for placebo effects. With Starstim, Sham mode is implemented by ramping up and down the current at the beginning/end of stimulation respectively, as it is during these times when the subject can feel the strongest sensations during stimulation.

In single-blind trials, the operator knows which stimulation type is being applied, but the subject doesn't.

In double-blind experiments, the goal is to have both operator and subject blind to which type of stimulation is being applied (e.g., active vs. sham, or anodal vs. cathodal, etc). See our detailed StarStim Double-Blind Mode Manual for more information on how to configure your experiments and NIC for double-blind trials.