A medical device for monitoring biological parameters through an Abreu Brain Thermal Tunnel (ABTT) is provided. By monitoring and analyzing the temperature of the ABTT, it is possible to diagnosis changes in a patient or subject under a variety of conditions, including predicting the course of medical conditions. Furthermore, since the ABTT is predictive, analysis of the ABTT may be used to control mechanisms for safety when an impending medical condition makes such operation hazardous.