Systems and methods are directed to generating and analyzing light. Spatial light response around a human fingertip in response to electrical stimulation is associated with the status of various body organs. A system that provides a particularized response indication based on spatial light response includes a camera, an electrical signal generator, a light source, a circuit, and a computer. The signal generator stimulates emission of light from the finger when the finger is at a position relative to the camera. The light source illuminates the finger at the position. The circuit activates the light source and the camera to obtain a first image of the finger at the position, activates the signal generator and the camera to obtain a second image of the emission of light from the finger at the position, determines a direction from the first image, determines a centroid from the second image, and determines a description of the second image in accordance with the direction and the centroid. The computer receives indicia of the description and provides the particularized response indication in accordance with the description, wherein the particularized response indication describes a status of various body organs.
