Neurophysiological and behavioral synchronization in group-living and sleeping mice

Area of Science:

• Neuroscience
• Behavioral Biology
• Sleep Science

Background:

• Social interactions are crucial for animal development and behavior.
• The impact of social interactions on sleep, a fundamental process, remains largely unexplored.

Purpose of the Study:

• To investigate how social interactions modulate sleep behavior and neurophysiology in mice.
• To understand the motivation behind social sleeping (huddling) and its effect on sleep architecture.

Main Methods:

• Utilized wireless neurophysiological devices for simultaneous, 24-hour recording of freely moving, co-living mice.
• Employed a novel behavioral apparatus to assess sleep location preference based on social contact availability.
• Applied deep learning for accurate classification of huddling behavior.

Main Results:

• Mice actively seek physical contact before and during sleep (huddling).
• Mice prioritize social contact over preferred sleep locations, indicating a strong motivation for physical closeness ('somatolonging').
• Social conditions significantly alter sleep architecture, with synchronized sleep-wake timing and non-rapid eye movement sleep (NREMS) intensity observed in co-sleeping mice. Rapid eye movement sleep (REMS) timing synchronized specifically in male siblings.

Conclusions:

• Social contact during sleep is a motivated behavior driven by 'somatolonging'.
• Sleep is highly plastic and socially dependent, with distinct neurophysiological modulations based on social context.
• Findings reveal coordinated sleep patterns in co-sleeping mice, with specific synchrony observed in male siblings.