Abstract: Method and apparatus for generating and selecting low-frequency time-domain signals capable of transducing a mammalian system, to produce an agent-specific effect on the system, are disclosed. Low-frequency time-domain signals are generated in the presence of an injected magnetic stimulus, and the resulting signals are selected by a scoring algorithm, and optionally, by testing each signal identified by the scoring algorithm for its ability to produce an agent-specific response in a in vitro system containing components that are responsive to the agent. The selected signals are used to transduce the mammalian system by applying the signals to an electromagnetic transduction coil that holds the sample.