Transcranial direct current stimulation integration with magnetic resonance imaging, magnetic resonance spectroscopy, near infrared spectroscopy imaging, and electroencephalography

Transcranial direct current stimulation provides researchers and clinicians with the ability to non-invasively modulate the firing rate of neurons. However, the focality and overall consequences of tDCS for neural systems is often unclear based on tDCS alone. When tDCS is paired with state-of-the-art neurophysiology, neuroimaging and spectroscopic techniques, researchers and clinicians can gain important insight into the neural underpinnings of tDCS effects, as well as gain novel insight into brain-behaviour relationships. In this chapter, we will consider approaches for integration of tDCS with magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), near infrared spectroscopy (NIRS) imaging, and electroencephalography (EEG). We will discuss technical considerations, benefits, limitations, and optimal application strategies for the integration of each methodology with transcranial direct current stimulation. This chapter will provide an important foundation for understanding "how" to integrate these technologies, as well as "when" integration can be of benefit for researchers and clinicians.