Optical data is obtained from a pair of breasts, employing a simultaneous bilateral referencing protocol, and is subsequently analyzed employing a self-referencing data analysis method. Optical measurements can be performed on both breasts simultaneously under various protocols, including resting-state measures and evoked responses. Sensing hardware and data collection protocols are economical and can be implemented without patient discomfort. The natural variance inherently associated with optical measures of the breast is reduced by: imposition of substantially symmetric boundary conditions collection of simultaneous bilateral dynamic measures referencing measurement data of one breast to measurement data from another.