Noninvasive brain stimulation is used across clinical, commercial, and research applications to change the brain in hopes of changing behavior, yet we don't fully understand how it changes brain activity. Using scalp EEG, we delineate how two common brain stimulation techniques, transcranial alternating current stimulation (tACS) and transcranial direct current stimulation (tDCS), affect auditory gamma responses in healthy adults. Whereas gamma frequency-tuned tACS adjusts the magnitude and timing of auditory gamma responses, both tACS and tDCS strengthen the gamma phase connectome, which is disrupted in numerous neurological and psychiatric disorders and may be a target for intervention.
Our research aims to uncover mechanistic explanations of the neural basis of human behavior, that is, move from where to how. Our goals are multifaceted: (1) advance fundamental science by discovering new knowledge using rigorous, reproducible methods; and (2) advance translational applications in neurotechnology, precision medicine, and product development that are grounded in rigorous science. In this project, we showcase how applying a repertoire of analytics - spanning signal processing, graph theory, and nonparametric statistics - to neurophysiological data can inform the design of therapeutic brain stimulation protocols. On the Scientific Sense podcast, we discussed ways to leverage these findings to combat cognitive decline in the elderly.
These scripts produce the results reported in:
- Jones, KT, Johnson, EL, Tauxe, ZS, Rojas, DC. Modulation of auditory gamma-band responses using transcranial electrical stimulation. Journal of Neurophysiology 123 (2020). DOI
Project data are available on OSF. These data have been prepared for analysis as described in the publication.
Publications or other papers using these scripts and/or data should cite the publication above.
Software:
- MATLAB 9.7 (R2019b; last tested with R2024b)
- Set General > MAT-Files > save -v7.3
- Fieldtrip (last tested with fieldtrip-20250114) - download
Notes:
- Open and run the batch script (run_batch) to run through all scripts and reproduce the published results.