An invention and method that generate dynamical shaped voltage-gradient geometries through a plurality of dual-modal electrode-contacts placed around the biological tissue in vivo. The geometry of the voltage gradient is optimized through a feedback mechanism from the plurality of dual-modal electrode-contacts that can record electric and magnetic field potentials in the biological tissue. A control controls the waveform signal between sets of electrode-contacts to generate dynamically shaped voltage gradients to modulate a specific set of properties in the biological tissue. A method of analysis for the recorded electric and magnetic field potentials is purposed to optimize the shape of the voltage-gradient geometry through modulation of the waveform signal that is sent through the dual-modal electrode-contacts.