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Chronomics, human time estimation, and aging.

Halberg F, Sothern RB, Cornélissen G, Czaplicki J - Clin Interv Aging (2008)

Bottom Line: Cycles of a half-week, a week, approximately 30 days, a half-year and a year, in self-assessed 1-minute estimation by RBS between 25 and 60 years of age in health, are mapped for the first time, compared and opposite effects are found.Circadian and infradian rhythm mapping is essential for a scrutiny of effects of aging.A approximately 30-day and a circannual component apparent at 25 years of age are not found later; cycles longer than a year are detected.

View Article: PubMed Central - PubMed

Affiliation: Halberg Chronobiology Center, University of Minnesota, Campus Mail Code 8609-MMC 8609, 420 Delaware St. S.E., Minneapolis, MN 55455, USA. halbe001@umn.edu

ABSTRACT

Background: Circadian rhythm stage affects many outcomes, including those of mental aging.

Methods: Estimations of 1 minute approximately 5 times/day for a year, 25 years apart, by a healthy male biomedical scientist (RBS), are analyzed by the extended cosinor.

Results: Cycles of a half-week, a week, approximately 30 days, a half-year and a year, in self-assessed 1-minute estimation by RBS between 25 and 60 years of age in health, are mapped for the first time, compared and opposite effects are found. For RBS at 60 vs at 25 years of age, it takes less time in the morning around 10:30 (P < 0.001), but not in the evening around 19:30 (P = 0.956), to estimate 1 minute.

Discussion: During the intervening decades, the time of estimating 1 minute differed greatly, dependent on circadian stage, being a linear decrease in the morning and increase in the evening, the latter modulated by a -33.6-year cycle.

Conclusion: Circadian and infradian rhythm mapping is essential for a scrutiny of effects of aging. A approximately 30-day and a circannual component apparent at 25 years of age are not found later; cycles longer than a year are detected. Rhythm stages await tests as markers for timing therapy in disease.

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The data of the first and last years of 1-minute estimation were stacked along the 24-hour scale. Whereas parameter tests did not detect any change in the characteristics of the 24-hour synchronized rhythm, a paired t-test comparing eight 3-hourly mean values shows a difference below the 5% level. Moreover, Student’s t-test on data in each of 8 equidistant bins reveal that at certain circadian stages, 1 minute passed faster in the last year than in the first year (year 35 vs year 1). This difference was statistically significant at all test times between 06:00 and 18:00 (in some of them with P < 0.001), but was not found between 18:00 and 06:00, suggesting that the change in 1-minute time estimation with age is circadian stage-dependent, with highly significant differences during part of the daily active phase, but not at other circadian times. In RBS, chronomics demonstrate interaction between the circadian rhythm’s stage and age.
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f4-cia-3-749: The data of the first and last years of 1-minute estimation were stacked along the 24-hour scale. Whereas parameter tests did not detect any change in the characteristics of the 24-hour synchronized rhythm, a paired t-test comparing eight 3-hourly mean values shows a difference below the 5% level. Moreover, Student’s t-test on data in each of 8 equidistant bins reveal that at certain circadian stages, 1 minute passed faster in the last year than in the first year (year 35 vs year 1). This difference was statistically significant at all test times between 06:00 and 18:00 (in some of them with P < 0.001), but was not found between 18:00 and 06:00, suggesting that the change in 1-minute time estimation with age is circadian stage-dependent, with highly significant differences during part of the daily active phase, but not at other circadian times. In RBS, chronomics demonstrate interaction between the circadian rhythm’s stage and age.

Mentions: Figure 4 provides a highly qualified yet clear answer to the question whether there is an acceleration of the subjective “minute” with age in RBS. This figure stacks data in two chronograms along the 24-hour scale, each summarizing a year’s data 35 years apart, at 25 vs 60 years of age, respectively. Without extrapolating to other subjects (Halberg et al 1981) and/or to the intervening years, admittedly great limitations, both the (sparsely documented) maxima and some of the (solidly documented) minima (numbers of TE at each time are given in parentheses) are numerically lower during year 35 than during the first year (Figure 4), ie, at 60 vs 25 years of age, suggesting acceleration. Figure 4 shows further that even if overall the time-structure-adjusted mean (MESOR) is numerically lower at an advanced age, the demonstration of an age change is not possible on this basis (P = 0.300). A circadian stage-dependence in Figure 4 is found by Student t-tests that show an aging effect in RBS to be not demonstrable at certain circadian stages, while it is statistically highly significant at other times of day; each result, that around 10:30 vs that at 19:30, is documented with relatively ample data.


Chronomics, human time estimation, and aging.

Halberg F, Sothern RB, Cornélissen G, Czaplicki J - Clin Interv Aging (2008)

The data of the first and last years of 1-minute estimation were stacked along the 24-hour scale. Whereas parameter tests did not detect any change in the characteristics of the 24-hour synchronized rhythm, a paired t-test comparing eight 3-hourly mean values shows a difference below the 5% level. Moreover, Student’s t-test on data in each of 8 equidistant bins reveal that at certain circadian stages, 1 minute passed faster in the last year than in the first year (year 35 vs year 1). This difference was statistically significant at all test times between 06:00 and 18:00 (in some of them with P < 0.001), but was not found between 18:00 and 06:00, suggesting that the change in 1-minute time estimation with age is circadian stage-dependent, with highly significant differences during part of the daily active phase, but not at other circadian times. In RBS, chronomics demonstrate interaction between the circadian rhythm’s stage and age.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2662403&req=5

f4-cia-3-749: The data of the first and last years of 1-minute estimation were stacked along the 24-hour scale. Whereas parameter tests did not detect any change in the characteristics of the 24-hour synchronized rhythm, a paired t-test comparing eight 3-hourly mean values shows a difference below the 5% level. Moreover, Student’s t-test on data in each of 8 equidistant bins reveal that at certain circadian stages, 1 minute passed faster in the last year than in the first year (year 35 vs year 1). This difference was statistically significant at all test times between 06:00 and 18:00 (in some of them with P < 0.001), but was not found between 18:00 and 06:00, suggesting that the change in 1-minute time estimation with age is circadian stage-dependent, with highly significant differences during part of the daily active phase, but not at other circadian times. In RBS, chronomics demonstrate interaction between the circadian rhythm’s stage and age.
Mentions: Figure 4 provides a highly qualified yet clear answer to the question whether there is an acceleration of the subjective “minute” with age in RBS. This figure stacks data in two chronograms along the 24-hour scale, each summarizing a year’s data 35 years apart, at 25 vs 60 years of age, respectively. Without extrapolating to other subjects (Halberg et al 1981) and/or to the intervening years, admittedly great limitations, both the (sparsely documented) maxima and some of the (solidly documented) minima (numbers of TE at each time are given in parentheses) are numerically lower during year 35 than during the first year (Figure 4), ie, at 60 vs 25 years of age, suggesting acceleration. Figure 4 shows further that even if overall the time-structure-adjusted mean (MESOR) is numerically lower at an advanced age, the demonstration of an age change is not possible on this basis (P = 0.300). A circadian stage-dependence in Figure 4 is found by Student t-tests that show an aging effect in RBS to be not demonstrable at certain circadian stages, while it is statistically highly significant at other times of day; each result, that around 10:30 vs that at 19:30, is documented with relatively ample data.

Bottom Line: Cycles of a half-week, a week, approximately 30 days, a half-year and a year, in self-assessed 1-minute estimation by RBS between 25 and 60 years of age in health, are mapped for the first time, compared and opposite effects are found.Circadian and infradian rhythm mapping is essential for a scrutiny of effects of aging.A approximately 30-day and a circannual component apparent at 25 years of age are not found later; cycles longer than a year are detected.

View Article: PubMed Central - PubMed

Affiliation: Halberg Chronobiology Center, University of Minnesota, Campus Mail Code 8609-MMC 8609, 420 Delaware St. S.E., Minneapolis, MN 55455, USA. halbe001@umn.edu

ABSTRACT

Background: Circadian rhythm stage affects many outcomes, including those of mental aging.

Methods: Estimations of 1 minute approximately 5 times/day for a year, 25 years apart, by a healthy male biomedical scientist (RBS), are analyzed by the extended cosinor.

Results: Cycles of a half-week, a week, approximately 30 days, a half-year and a year, in self-assessed 1-minute estimation by RBS between 25 and 60 years of age in health, are mapped for the first time, compared and opposite effects are found. For RBS at 60 vs at 25 years of age, it takes less time in the morning around 10:30 (P < 0.001), but not in the evening around 19:30 (P = 0.956), to estimate 1 minute.

Discussion: During the intervening decades, the time of estimating 1 minute differed greatly, dependent on circadian stage, being a linear decrease in the morning and increase in the evening, the latter modulated by a -33.6-year cycle.

Conclusion: Circadian and infradian rhythm mapping is essential for a scrutiny of effects of aging. A approximately 30-day and a circannual component apparent at 25 years of age are not found later; cycles longer than a year are detected. Rhythm stages await tests as markers for timing therapy in disease.

Show MeSH