A device, system, and method for diagnosis, prognosis, and treatment of diseases or disorders, such as psychiatric or psychological disorders characterized at least in part by anxiety. The device includes a heart monitor configured to monitor at least a heart rate of a first individual, and is configured to regulate one or more properties of one or more biofeedback elements according to at least the heart rate of the first individual. The biofeedback elements may include one or more of a light element, a sound element, and a temperature element. The biofeedback elements are incorporated into an initial environment of the first individual to form a resultant environment, which may influence one or more biological processes of the first individual. The system may include a plurality of devices configured to regulate the one or more properties of the one or more biofeedback elements.
