Date of Completion

Spring 5-1-2021

Thesis Advisor(s)

Eiling Yee

Honors Major

Physiology and Neurobiology


Cognition and Perception | Cognitive Psychology


Cognitive control is the ability to focus on relevant stimuli while disregarding irrelevant stimuli and is thought to be supported by the prefrontal cortex (see Miller & Cohen, 2001). Transcranial Direct Current Stimulation (tDCS) is a noninvasive brain stimulation technique that modulates the activity of underlying cortex regions through an electric current provided by two or more electrodes on the scalp. This study looks to determine whether anodal tDCS over the left prefrontal cortex can be used to increase cognitive control in healthy participants. Using an F3-RSO montage in a mixed between and within subjects design (with sham vs. anodal stimulation as the between factor, and pre- vs. post-stimulation as the within factor), we observed no increase in cognitive control as measured via comparing pre- and post-test Flanker and Stroop task congruency effects. However, there was substantial variability across our sham vs anodal participants in pre-test congruency effects, which persisted to the post-test. . Although there was no effect with this particular montage and stimulation parameters, it remains possible that with a different montage, anodal tDCS over the prefrontal cortex could increase cognitive control in participants. This study demonstrates the importance of considering baseline differences in cognitive control.