Time in a timeless environment

The fact that every organism possesses an endogenous biological clock can be established when they are made to live in conditions of timelessness. How do human beings perform under such conditions? Human isolation facilities provide such timeless environments where human beings can live comfortably while performing various bodily activities as dictated by their endogenous clock. In this article, I narrate my personal experience in the isolation facility at Madurai Kamaraj University. My stay (on three occasions) has led to the important finding that the menstrual cycle in a human female is not coupled to the sleep-wake cycle. I also describe how such experiments can be useful in the context of shift-working, jet-lag and space studies.