Sleep fragmentation disrupts vocal interactions in rats

ABSTRACT

Repeated interruption of the sleep cycle, commonly known as sleep fragmentation, is associated with a plethora of health issues, ranging from mood swings and memory loss to severe neurodegenerative disorders. Despite being a significant health problem with consequences on the social lives of individuals, its effect on vocal communication has been poorly studied. Here we show that sleep fragmentation induces a decrease in vocal production of a social rodent, without altering the acoustic characteristics of the vocalisations emitted. We conducted an experimental study using Rattus norvegicus rats, known for their ultrasonic vocal repertoire, in which we frequently woke pairs of individuals during their daily sleeping period. The rats whose sleep was artificially fragmented produced fewer vocalisations during their active periods than control pairs whose sleep was not disturbed. This decrease in vocal activity occurred after only two phases of fragmented sleep and was maintained throughout the 4 weeks of the experimentation. Conversely, sleep fragmentation had no effect on the rats’ vocal repertoire. Our results demonstrate that fragmented sleep impacts vocal interactions and emotional expression in a social mammal, and that this effect is maintained over weeks without recovering.

KEYWORDS:

• Sleep disorder
• sleep fragmentation
• vocalisation
• social interactions
• bioacoustics
• rats

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/09524622.2024.2303691