1. A method of preferentially stimulating a portion of neural tissue including a first type of neurons and a second type of neurons, the method comprising the steps of: defining a waveform characterizing an electrical stimulus, the waveform including an amplitude-modulated wave of the electric stimulus; and applying the electrical stimulus having the defined waveform to a stimulating element located in proximity to the neural tissue to selectively activate the first type of neurons while leaving the second type of neurons one of substantially unaffected and suppressed in response to the electrical stimulus.