This protocol is intended to study the differences between a rectal temperature probe and an approved wireless and indigestible thermometer during a WBH session. The current standard in monitoring core body temperature is the usage of an indwelling rectal thermometer. Many patients and potential study subjects, however, decline receiving the treatment, due to the discomfort of using this measuring method and a wireless measuring device would open the possibility for those patients to receive a treatment. The primary endpoint for example of a treatment for MDD is currently defined with reaching a rectal temperature of 38.5 C. However, due to the proximity of the probe to the body's surface, the core body temperature will vary from the rectal temperature and the comparison between the two methods with a validation of the wireless device is necessary.