An examination of social rhythms in a clinical insomnia population and good sleeper comparison group

Insomnia had generally been conceptualized as a nighttime disorder, while the daytime experience of insomnia has been largely ignored. However, there are several lines of research suggesting daytime experiences as well as daytime behaviours are equally important. For example, daily behavioural routines commonly referred to as social rhythms (e.g., exercise, attendance of school or work, recreation, engagement in social activities) have been identified as potential zeitgebers (i.e., time cues that help to regulate the biological clock). Previous research has shown that regulating behavioural zeitgebers may have promising benefits for sleep. As such, this study examined the daytime activities in a clinical insomnia population and a good sleeper comparison group. Participants (N = 69) prospectively monitored their sleep and daily activities for a two-week period, while wearing a wrist actiwatch. Those with insomnia appear to engage in activities characterized by significantly less regularity than good sleepers. However, those with insomnia were found to engage in similar levels of daily activities compared to good sleepers. Findings from this study highlight the relative importance of daytime activities on this supposed nighttime process. Accordingly, future research would benefit from testing treatment components that focus on regulating daytime activities, which would likely improve treatment outcomes.