A new study published in the Journal of Physiology explores how missing sleep during the dark hours of the night can affect the production of melatonin, reports Earth.com.

The hormone, which helps regulate sleep and is produced by the brain during the night, can be suppressed if someone is frequently exposed to light before sleep.

In a 9- to 10-day inpatient study at Brigham and Women’s Hospital, researchers used continuous and intermittent light during sleeping periods to test whether melatonin suppression and the circadian rhythm are connected. The study included tight control over the participants activity levels and sleep/wake schedule.

The team hopes to find whether a correlation between melatonin levels and circadian phase resetting – the process that sets the internal clock using day and night cues from one’s environment – might equal causation.