A Pilot Test of Mood and Circadian Rhythm Mechanisms Driving Binge Eating

Study Summary

Mood and circadian rhythm disruptions are associated with binge eating (BE). BE is a discrete, episodic behavior characterized by 1) eating an objectively large amount of food and 2) experiencing a subjective sense of loss of control. BE episodes are often preceded by negative mood states, and a subtype of individuals with BE has high levels of negative moods. This group has more comorbid psychopathology and a poorer response to treatment. Thus, understanding the role of negative mood is a critical area for research on BE. Individuals with BE demonstrate disruptions in several circadian rhythms, including diurnal meal timing, hormone patterns (e.g., daily cortisol rhythms), and mood variations. The most potent synchronizer of circadian rhythms is light. Thus, exposure to light may explain other phenomena that fluctuate similarly, such as mood and the occurrence of BE. Mood is subject to the influence of light, and BE is also influenced by exposure to bright light. It is unknown whether regulating circadian rhythms via regular exposure to light improves BE through its effects on mood or via changes in other biological or behavioral rhythms. This knowledge can inform the development of treatments targeting biobehavioral mechanisms that maintain BE and indicate for whom this may be most effective. This project aims to test the roles of negative mood and circadian rhythms in the relationship between light exposure and BE and identify subtypes of individuals in whom this effect is strong. The investigators hypothesize that individuals exposed to less natural bright light will experience more frequent BE, more negative mood, and a blunted morning cortisol response. The investigators further hypothesize that manipulating exposure to artificial bright light will reduce the frequency of BE and negative mood and increase the morning cortisol response. Finally, the investigators hypothesize that the effects of this artificial bright light exposure on BE frequency will be media

Primary Outcome

The cortisol awakening response will estimated from saliva samples collected at home via passive drool (0.5 ml) at three times: immediately upon waking, 15 minutes after waking, and 30 minutes after waking. The curve of this response can be estimated from these three measurements. The response will be averaged over two consecutive days of collection and then compared between the two intervention phases to quantify the change in the awakening response accounted for by the interventions while cont

Conditions Studied

Interventions

• DEVICE Bright Light Exposure
• DEVICE Natural Light Exposure

Study Locations (1)