Aging in Mice Reduces the Ability to Sustain Sleep/Wake States
Figure 5
Aging slows theta peak frequency (TPF) and decreases slow wave activity (SWA) at low frequencies (0.5–1.5 Hz).
A. Wake EEG spectra calculated during the dark period for young and old mice. Aged animals show lower power in the higher frequency range. B. EEG spectra for NREM sleep generated during the light period for young and aged mice. Aging did not profoundly affect NREM spectral profile. C. EEG spectra of REM sleep computed during the light phase for young and old mice. D. Theta peak frequency (TPF) for wake and REM EEG during the dark and light phase, respectively. TPF slowed with aging for both states. E. Slow wave activity (0.5–4 Hz, SWA) of NREM sleep for young and old mice expressed relative to the last 4 hours of the light period ( = 100%) for each animal. Grey area denotes the dark period. F. Low frequency (0.5–1.5) SWA of NREM sleep young and old mice expressed relative to the last 4 hours of the light period ( = 100%) for each animal. Grey area denotes the dark period. Mean ± s.e.m., gray bar and * indicate p<0.05.
