During the period 1980–1986, optical imaging expanded as a noninvasive modality to probe functional organization in living cortex, leveraging intrinsic light-contrast changes to map neural activity. The field saw rapid advances in high-resolution, surface-sensitive imaging and in the development of computational models to predict light transport in tissue, supporting diverse illumination scenarios. The convergence of instrument innovations and analytical frameworks fostered new experimental paradigms that linked optical signals to physiological processes, setting the stage for widespread functional mapping with optical methods.