Biological sex differences in sleep of male and female c57bl/6 mice

Sleep is used as a physiological outcome in research, however, few studies have disaggregated sleep data based on sex. We investigated biological sex differences in sleep under normal physiological conditions using male and female C57BL/6 mice (n = 267 from 17 cohorts). Physiological parameters were recorded for 48-hours (2 days) using non-invasive piezoelectric cages to determine total sleep, non-rapid eye movement (NREM) sleep, rapid eye movement (REM) sleep, and wakefulness (WAKE). To investigate sleep differences between sexes we fit hierarchical generalized linear mixed models with nonlinear time effects. We found substantial sex differences in the sleep of C57BL/6 mice. Female mice slept less overall, specifically during the dark period, with less NREM sleep compared to males. Females also exhibited more REM sleep and WAKE. Females had shorter total and NREM sleep bout lengths compared to males. During the light period, REM bout lengths and WAKE bout lengths were similar between s..., Adult (8-20 weeks-old) male and female C57BL/6 mice from 17 total sex-specific cohorts were used (males n = 140; females n = 127). All mice were bred in-house from breeder pairs obtained from Jackson Laboratories (Bar Harbor, ME). For all studies, mice were singly housed and maintained on a 12-hour light:dark cycle (200 lux, cool white, fluorescent light) at an ambient temperature of 24°C ± 2°C. All mice were acclimated to non-invasive piezoelectric sleep cages for a minimum of 5 days prior to initiation of data collection and were fed a normal diet of standard rodent chow, and food and water were available ab libitum. Physiological parameters were recorded for 48-hours using non-invasive piezoelectric cages to determine total sleep, non-rapid eye movement (NREM) sleep, rapid eye movement (REM) sleep, and wakefulness (WAKE).The non-invasive piezoelectric cage system used Polyvinylidine Difluoride sensors on the cage floor to measure movement and breathing patterns. The piezoelectric sig..., , # Data From: Biological Sex Differences in Sleep of Male and Female C57BL/6 Mice

[https://doi.org/10.5061/dryad.76hdr7t39](https://doi.org/10.5061/dryad.76hdr7t39)

## Description of the data and file structure

**Sex_Differences_Sleep.csv**:  File containing all sleep data from two continuous days under normal physiological conditions.

animal_ID – Unique identifier for individual mice.
Cohort – Categorical variable denoting the experimental cohort each mouse was in.
Sex – Biological sex of mouse
Timepoint – Sleep was measured for 2 consecutive days. Categorical variable where ‘A’ denotes the first 24 h and ‘B’ denotes the second 24 h.
Time – Categorical variable denoting the time of day (hour) that sleep-wake data were collected.
ZT – Categorical variable denoting zeitgeber time (ZT) where ZT0 was the time the lights in the housing room were turned on and ZT12 was lights off.
LD Cycle – Categorical variable denoting the light (L) or dark (D) cycle for each hour data were collected.
P...