Transcranial Direct Current Stimulation Electrodes

  • Niranjan Khadka
  • Adam J. Woods
  • Marom BiksonEmail author


Electrodes serve as the interface between transcranial direct current stimulators and the human body. Electrodes are the method for delivering current from an electrical stimulator to the brain. If prepared poorly, they can significantly reduce the degree of brain stimulation delivered. The size, number, and relative location of electrodes control the distribution of current in the brain, whether stimulation is focal or broad, and levels of stimulation intensity within the tissue. Thus, careful consideration is required for how electrodes are prepared and applied in transcranial direct current stimulation. This chapter will discuss the typical construction of the electrode assembly, differences in commonly available electrodes, high definition versus conventional electrodes, and contact mediums commonly used for transcranial direct current stimulation. This chapter will also describe approaches for consistent preparation and placement of the electrode assembly on the head. This chapter will give special considerations to methods for avoiding oversaturation of electrodes, safety considerations for avoiding burns on the scalp, and methods for avoiding common mistakes in preparation and placement of electrodes that undermine the valid and consistent application of transcranial direct current stimulation.


tDCS Electrode assembly Safety Design Tolerability Reproducibility 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Biomedical EngineeringThe City College of New York, CUNY, City College Center for Discovery and InnovationNew YorkUSA
  2. 2.Center for Cognitive Aging and Memory (CAM), McKnight Brain Institute, Department of Clinical and Health Psychology, College of Public Health and Health ProfessionsUniversity of FloridaGainesvilleUSA
  3. 3.Department of Biomedical EngineeringThe City College of New YorkNew YorkUSA

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