9
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: not found
      • Article: not found

      The use of Constant Routines in Unmasking the Endogenous Component of Human Circadian Rhythms

      ,
      Chronobiology International
      Informa UK Limited

      Read this article at

      ScienceOpenPublisher
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Related collections

          Most cited references19

          • Record: found
          • Abstract: not found
          • Article: not found

          Exogenous and Endogenous Components in Circadian Rhythms

          J. Aschoff (1960)
            Bookmark
            • Record: found
            • Abstract: not found
            • Book: not found

            The Circadian System of Man

              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Adaptation to abrupt time shifts of the oscillator(s) controlling human circadian rhythms.

              1. Thirty-six subjects in an isolation unit were subjected to time shifts of 12 hr, or of 8 hr in either direction. 2. The rhythms of body temperature and excretion of eight urinary constituents were studied before and after the shift, both on a usual nychthemeral routine and during 24 hr when they remained under constant conditions, awake, engaged in light, mainly sedentary activity, and consuming identical food and fluid every hour. 3. The rhythms on nychthemeral routine were defined by fitting cosine curves. On constant routine the rhythm after the shift was cross-correlated with the original rhythm, either with variable delay (or advance) or with an additive mixture between this variably shifted rhythm and the unshifted or a fully shifted rhythm. The process yielding the highest correlation coefficient was accepted as the best descriptor of the nature of adaptation. 4. A combination of two rhythms was observed more often for urinary sodium, chloride and phosphate than for other variables. 5. Adaptation appeared to have proceeded further after westward than eastward shifts, and this difference was particularly noticeable for urinary potassium, sodium and chloride. 6. Partial adaptation usually involved a phase delay, even after an eastward shift when a cumulative delay of 16 hr would be needed to achieve full adaptation and re-entrainment. 7. Observations under nychthemeral conditions often gave a false idea of the degree of adaptation. In particular, after an eastward shift the phase of the rhythms appeared to shift in the appropriate direction when studied under nychthemeral conditions whereas the endogenous oscillator either showed no consistent behaviour or, in the control of urate excretion, a shift in the wrong direction. 8. The implications for people undergoing time shifts, in the course of shift work or transmeridional flights, are indicated.
                Bookmark

                Author and article information

                Journal
                Chronobiology International
                Chronobiology International
                Informa UK Limited
                0742-0528
                1525-6073
                July 07 2009
                January 1984
                July 07 2009
                January 1984
                : 1
                : 3
                : 205-216
                Article
                10.3109/07420528409063897
                06770a5d-da59-44eb-8ed1-c956751dc3aa
                © 1984
                History

                Comments

                Comment on this article