Fig. 9

Repetitive mild traumatic brain injury (rmTBI) results in sleep pattern disturbances (a). Mice repetitive rmTBI exhibit a significant reduction in NREM sleep as well as a significant increase in wake time over the course of 24 h (Tukey). *p < 0.05, compared to control mice. b Quality of NREM sleep is disrupted by rmTBI. Power spectral analysis demonstrated a significant rightward theta shift in rmTBI animals. Control animals displayed a significantly higher power spectrum for 1–2 Hz, compared to rmTBI groups. Single and repetitive rmTBI mice had a significantly higher frequency at 5 Hz, compared to age-matched controls (Tukey). Single rmTBI mice also had a significant difference at 12 and 13 Hz, compared to control mice (Tukey). *p < 0.05, repetitive rmTBI versus control mice; ^#p < 0.05, single rmTBI versus control mice. c Repetitive rmTBI mice exhibited a greater number of NREM episodes, compared to the single rmTBI and control groups, with d significantly reduced episode lengths (Tukey). *p < 0.05. Values are mean ± SD. NREM, non-rapid eye movement; REM, rapid eye movement