1. A measurement device comprising: a light source which emits at least one kind of measurement light belonging to a predetermined wavelength band toward a measurement region formed of at least part of a living body; a detection unit in which a plurality of sensors is regularly arranged in a predetermined arrangement and which detects the measurement light emitted from the light source and passing through the living body with the plurality of sensors; and an analysis unit which performs analysis processing of specifying a measurement position for measuring information on pulsation along with activities of the living body from the measurement region based on a temporal change in an amount of light of the detected measurement light by use of a detection result detected by the detection unit.