Abstract
Within western societies it is commonplace for couples to share a bed. Yet there has been remarkably little research carried out on couples’ sleep. This paper draws upon actigraphy, audio diary and questionnaire data from both partners in 36 heterosexual couples (age 20-59) and aims to quantify the extent to which it is important to take the dyadic nature of sleep-wake cycles into account. It achieves this through two interrelated aims: (i) to use Hierarchical Linear Models to measure dyadic interdependence in actigraphically recorded variables; and (ii) to investigate how much of this dyadic interdependence truly results from couple dynamics. The variables with the most significant couple interdependency were ‘Actual bed time’, ‘Sleep latency’, ‘Light/Dark ratio’ and ‘Wake bouts’. The paper concludes by suggesting that interdependence may be the defining feature of couples’ sleep and that we need to employ analytic approaches which both acknowledge this and which are sensitive to the possibilities that not all aspects of sleep will behave in the same way.