Systems and methods for applying and/or receiving electrical, magnetic, magnetoelectric, vibratory, or electromagnetic signals to biological tissues are described. In some embodiments, one or more of a body, a conductor, and an electrode may be provided. In some embodiments, a filament may be used as an electrode and may be placed in contact with a biological tissue portion. In some embodiments, a signal may be applied and/or received via the filament or other electrode.