Ultradian Rhythm (90 min)
1.85 × 10⁻⁴ Hz
A cycle of about 90 minutes, which is about 0.000185 Hz (1 ÷ 5,400 seconds).
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About this number
A cycle of about 90 minutes, which is about 0.000185 Hz (1 ÷ 5,400 seconds). "Ultradian" describes a cycle that repeats more than once in a 24-hour day. In sleep, the cycle between non-REM and REM sleep averages about 90 minutes. Nathaniel Kleitman proposed that the same cycle continues while awake and called it the basic rest-activity cycle (BRAC). That proposal is contested.
Facts
- Frequency
- 1.85 × 10⁻⁴ Hz
- One cycle takes
- 1.50 hours
- Kind of statement
- Physical measurement
- Filed under
- Body rhythms
Sources
- Body rhythms
Heart rate, breathing rate, the daily clock and the sleep cycle.
C. A. Czeisler et al., Science 284 (1999) 2177–2181. N. Kleitman, Sleep 5 (1982) 311–317. J. Moses et al., Nature 265 (1977) 360–361. A. Zaccaro et al., Frontiers in Human Neuroscience 12 (2018) 353.