In addition to experimental approaches, the support provided under this FOA might enable calculations, simulations, computational models, or other mathematical techniques for demonstrating that the signal sources and/or measurement technologies are theoretically capable of meeting the demands of large-scale recording or manipulation of circuit activity in humans or in animal models. The support might also be used for building and testing phantoms, prototypes, in-vitro or other bench-top models in order to validate underlying theoretical assumptions in preparation for future FOAs aimed at testing in animal models. Invasive or non-invasive approaches are sought that will ultimately enable or reduce the current barriers to large-scale recording or manipulation of neural activity, and that would ultimately be compatible with experiments in humans or behaving animals. Applications are encouraged from any qualified individuals, including physicists, engineers, theoreticians, and scientists, especially those not typically involved with neuroscience research.