Who is disrupting whom? Examining the nighttime activity patterns of humans and their dogs.

Few studies have examined the nighttime dynamic between humans and dogs, but existing research suggests dogs can disrupt human sleep. In this study, we examined the nighttime activity of 25 Canadian participants, totaling 38 human-dog pairs using accelerometers and survey data. We used linear mixed effects models to assess the drivers of variability in both human sleep and dog nighttime activity, and a generalized linear model to assess the effects of demographic variables on self-reported sleep quality. None of the variables significantly affected objective sleep measures in humans or dog nighttime activity. Dog sleeping location did not affect human perceived sleep quality, but having multiple dogs was associated with poorer subjective sleep (p = 0.042). Human and dog nighttime activities were found to be significantly correlated. Additionally, we conducted a time series analysis to determine lagged correlations between human and dog activities within five minutes. Among the 61% dyads that showed correlation in activity states, human activity preceding dog activity (45%) occurred more often than dog activity preceding human activity (18%). In 36% of dyads, activity was synchronized within the same 1-minute period. Overall, co-sleeping (i.e., bedsharing) had no effect on sleep duration or efficiency in humans or nighttime activity in dogs. The only significant predictor we found was the presence of other dogs, which affected subjective but not objective human sleep quality, revealing a discrepancy between self-reported and objectively measured sleep. Both humans and their dogs impact the nighttime activity of one another, demonstrating our species' inseparable and reciprocal relationship.