Systems, methods, and computer program products for determining a physiological state of an individual. A thermal image of the individual is analyzed to identify thermally responsive and thermally non-responsive regions of the individual. A baseline temperature is determined from the portions of the thermal image covering thermally non-responsive regions, and a response temperature is determined from the portions of the thermal image covering the thermally responsive regions. If the difference between the baseline temperature and the response temperature exceeds a threshold, a determination is made that the individual is having a threat response. This determination may trigger transmission of an alert signal to an emergency responder, who may then locate the individual for further investigation. Thermal images of individuals taken during interrogations may be analyzed in a similar manner to determine if an individual is being deceptive.
