1. A method for recognizing awareness in a subject comprising the steps of: a) acquiring, using an optical imaging system, optical imaging data from at least one cortical region of the brain of the subject over a time period; b) measuring, using the optical imaging data, at least one hemodynamic parameter in the at least one cortical region of the brain of the subject; c) identifying a variation pattern in the measured hemodynamic parameters; d) comparing the variation pattern to at least one predetermined variation pattern associated with subject awareness to determine a substantial similarity between the variation pattern and the predetermined variation pattern; and e) providing an indication of awareness of the subject.