SLEEP 2011 Abstract Supplement

A. Basic Science III. Ontogeny/Aging
remain important areas of investigation. Here we report the effects of a
mild CPSR protocol on young (4-month), middle-aged (12-month) and
old (18-month) rats.
Methods: Young, middle-aged and old male Fischer-344 rats had electroencephalogram
(EEG) and electromyogram (EMG) recording electrodes
surgically implanted. After recovery and acclimation to sleep
chambers, rats were subjected to a mild CPSR protocol using an automated
system that records EEG/EMG in real-time and uses an autoscoring
program to start a slowly rotating bar in the animal’s cage upon
detection of sleep onset (Pinnacle Technology, Inc.). EEG/EMG were
visually scored in ten-second epochs as belonging to one of the following
vigilance states: wake, rapid eye movement (REM) and non-REM
(NREM) sleep.
Results: The mild CPSR protocol utilized in this study consistently resulted
in an approximately 25% reduction in daily sleep amount during
CPSR in the different age groups. REM sleep was particularly reduced
when wakefulness was enforced. Preliminary EEG analyses suggest that
age-dependent differences in homeostatic processes during recovery
sleep and wake exist.
Conclusion: Young, middle-aged and old rats exhibit similar sleep-state
responses to mild CPSR, including a failure to elicit increased recovery
sleep in spite of accumulating sleep debt. EEG spectral analysis is expected
to reveal the dynamics of homeostatic sleep regulation in animals
of different age groups, which may yield insight into how the regulation
of sleep is affected by CPSR and influenced by aging.
Support (If Any): This work was supported by NIH 5P01AG011412-14
and 5T32HL07909-13.
0067
AGE-RELATED CHANGES OF EEG POWER AND
COHERENCE IN THE SLEEP SLOW-WAVE FREQUENCY
RANGE
Kurth S 1 , Ringli M 1 , Geiger A 1 , LeBourgeois M 2,3 , Jenni OG 1 , Huber R 1
1
Child Development Center, Children’s University Hospital Zurich,
Zurich, Switzerland, 2 University of Colorado at Boulder, Department
of Integrative Physiology, Boulder, CO, USA, 3 The Warren Alpert
Medical School of Brown University, Department of Psychiatry and
Human Behavior, Providence, RI, USA
Introduction: EEG power in the slow-wave (SW) frequency range
(1-4.5 Hz) is a well established electrophysiological marker of sleep
homeostasis. Moreover, SW-power was suggested to mirror cortical
maturation. EEG coherence, in waking and sleep, is thought to reflect
connectivity of underlying brain regions. Thus, the combination of the
two EEG measures may reflect the maturation of basic cognitive functions.
We therefore assessed SW-power and SW-coherence in developing
human subjects.
Methods: High-density sleep EEG (128 channels) was assessed in 63
subjects (2-26 years). The first 60 min of sleep stage N2 and N3 were
analyzed. For the SW-range EEG power was calculated for all channels
and EEG coherence for a selection of channels (Fp1F3-F3C3, Fp2F4-
F4C4, F3C3-C3P3, F4C4-C4P4, C3P3-P3O1, C4P4-P4O2, Fp1F3-
P3O1, Fp2F4-P4O2).
Results: SW-power exhibited an initial increase, a peak in late childhood
and a decrease thereafter (cubic fit for C4A1 R 2 =.73, p