Methods for neuromodulation using waveform signals. In certain embodiments, an input waveform is obtained from a signal source site in a source subject and an output waveform is applied to a target site in a target subject. The source subject is a human or animal and the signal source site is in the nervous system, including the brain. The source subject and target subject are the same subjects or different subjects. The output waveform is identical to the input waveform or derived from the input waveform. In some embodiments, the output waveform is modified in response to physiologic feedback. Also provided are systems for neuromodulation using waveform signals.