2021 - Ultrasound mediated cellular deflection results in cellular depolarization
Buffer Solution Publication in Advanced Science (2021)
Vasan A., Orosco J., Magara U., Duque M., Weiss C., Tufail Y., Chalasani S.H., Friend J.
Advanced Science (2021) doi:10.1002/advs.202101950
Existing methods to stimulate neural activity include electrical optical and chemical techniques. They have enabled the development of novel therapies that are used in clinical settings, in addition to helping understand aspects of neural function and disease mechanisms. Despite their beneficial impact, these approaches are fundamentally limited. Electrical stimulation is invasive, requiring direct contact with the target of interest. Inserting electrodes into the brain may lead to inflammation, bleeding, cell death, and local cytokine concentration increases in microglia that precipitate astrocyte formation around the electrodes that, in turn, reduce long-term effectiveness. In addition, it may have non-specific effects depending on the electric field generated by the electrodes and the stimulation parameters used. Transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (tMS) are new and non-invasive, yet they have poor spatial resolution on the order of 1 cm. Furthermore, approaches combining genetic tools with light or small molecules achieve cellular specificity. Optogenetics, which involves the use of light and genetically encoded membrane proteins, has enabled elucidation of cellular circuits in animal models. However, it remains an invasive technique and applications are limited by the depth of penetration of light in tissue. In contrast, chemogenetics, using small molecule sensitive designer receptors, is limited by poor temporal resolution and is unfortunately impractical for many neural applications that require millisecond response times