Objective: Entrainment to the day—night cycle is critical for infant sleep and social development. Synchronization of infant circadian systems with the social 24-hr day may require maternal activity signals as an entraining cue. This descriptive and exploratory research examines the activity level and circadian pattern in mothers and infants. Method: Twenty-two healthy mothers and their infants (postnatal age 49.8 ± 17.1 days) wore actigraph monitors for seven days. Daytime (06:00—21:59) and nighttime (22:00—05:59) activity levels and circadian parameters of rest—activity patterns (i.e., mesor, amplitude, acrophase, and 24-hr cosinor fit) were calculated. Results: Mothers and infants were significantly more active during the day than at night. The goodness-of-fit index for the model (R2) indicates that circadian rhythm accounted for a mean of 29 ± 10% and 12 ± 8% of the variability in maternal and infant activity, respectively. Acrophase of activity occurred at 15:46 ± 1:07 for the mothers and 15:20 ± 1:21 for the infants. The mean within-dyad correlation of activity counts was r = .46 ± .11, and the within-dyad correlation was associated with the amplitude (r = .66, p < .01) and 24-hr cosinor fit of infant activity (r = .67, p < .01). Conclusions: Our findings suggest maternal rhythms as a possible exogenous influence on shaping an infant’s emerging rhythms and synchronizing them with the external light—dark cycle. Strong pattern synchrony between maternal and infant activity may support infant circadian entrainment and enhance a regular 24-hr sleep—wake schedule during the early postnatal weeks.
Armitage, R., Flynn, H., Hoffmann, R., Vazquez, D., Lopez, J., & Marcus, S. ( 2009). Early developmental changes in sleep in infants: The impact of maternal depression. Sleep, 32, 693-696.
2.
Barnard, K.E. ( 1999). Beginning rhythms: The emerging process of sleep wake behaviors and self-regulation. Seattle, WA: NCAST, University of Washington.
3.
Borbély, A.A. ( 1982). A two process model of sleep regulation. Human Neurobiology, 1, 195-204.
4.
Borbély, A.A., Achermann, P., Trachsel, L., & Tobler, I. ( 1989). Sleep initiation and initial sleep intensity: Interactions of homeostatic and circadian mechanisms. Journal of Biological Rhythms, 4, 149-160.
5.
Boyce, P., Stubbs, J., & Todd, A. ( 1993). The Edinburgh Postnatal Depression Scale: Validation for anAustralian sample. Australian and New Zealand Journal of Psychiatry, 27, 472-476.
6.
Cohen, J. ( 1987). Statistical power analysis for the behavioral sciences (Rev. ed.). Hillsdale, NJ: Lawrence Erlbaum.
7.
Cox, J.L., Holden, J.M., & Sagovsky, R. ( 1987). Detection of postnatal depression. Development of the 10-item Edinburgh Postnatal Depression Scale. British Journal of Psychiatry, 150, 782-786.
8.
Daan, S., Beersma, D.G., & Borbely, A.A. ( 1984). Timing of human sleep: Recovery process gated by a circadian pacemaker. American Journal of Physiology, 246, R161-R183.
9.
Dijk, D.J., & Czeisler, C.A. (1995). Contribution of the circadian pacemaker and the sleep homeostat to sleep propensity, sleep structure, electroencephalographic slow waves, and sleep spindle activity in humans. Journal of Neuroscience, 15, 3526-3538.
10.
Feldman, R., & Eidelman, A.I. (2003). Skin-to-skin contact (kangaroo care) accelerates autonomic and neurobehavioural maturation in preterm infants . Developmental Medicine and Child Neurology, 45, 274-281.
11.
Feldman, R., & Eidelman, A.I. (2004). Parent-infant synchrony and the social-emotional development of triplets. Developmental Psychology, 40, 1133-1147.
12.
Feldman, R., Greenbaum, C.W., & Yirmiya, N. ( 1999). Mother-infant affect synchrony as an antecedent of the emergence of self-control. Developmental Psychology, 35, 223-231.
13.
Freudigman, K., & Thoman, E.B. ( 1994). Ultradian and diurnal cyclicity in the sleep states of newborn infants during the first two postnatal days. Early Human Development, 38, 67-80.
14.
Jenni, O.G., Deboer, T., & Achermann, P. ( 2006). Development of the 24-h rest-activity pattern in human infants. Infant Behavior and Development, 29, 143-152.
15.
Keefe, M.R. ( 1987). Comparison of neonatal nighttime sleep-wake patterns in nursery versus rooming-in environments. Nursing Research , 36, 140-144.
16.
Korte, J., Hoehn, T., & Siegmund, R. ( 2004). Actigraphic recordings of activity-rest rhythms of neonates born by different delivery modes. Chronobiology International , 21, 95-106.
17.
Lentz, M.J. ( 1990). Time series-Issues in sampling. Western Journal of Nursing Research, 12, 123-127.
18.
Lohr, B., & Siegmund, R. ( 1999). Ultradian and circadian rhythms of sleep-wake and food-intake behavior during early infancy. Chronobiology International , 16, 129-148.
19.
McGraw, K., Hoffmann, R., Harker, C., & Herman, J.H. ( 1999). The development of circadian rhythms in a human infant . Sleep, 22, 303-310.
20.
Mirmiran, M., Kok, J.H., Boer, K., & Wolf, H. ( 1992). Perinatal development of human circadian rhythms: Role of the foetal biological clock. Neuroscience and Biobehavioral Reviews, 16, 371-378.
21.
Monk, T.H. ( 1987). Parameters of the circadian temperature rhythm using sparse and irregular sampling. Psychophysiology, 24, 236-242.
22.
Murray, L., & Carothers, A.D. (1990). The validation of the Edinburgh Post-natal Depression Scale on a community sample. British Journal of Psychiatry, 157, 288-290.
23.
Nelson, W., Tong, Y.L., Lee, J.K., & Halberg, F. ( 1979). Methods for cosinor-rhythmometry. Chronobiologia , 6, 305-323.
24.
Nishihara, K., & Horiuchi, S. ( 1998). Changes in sleep patterns of young women from late pregnancy to postpartum: Relationships to their infants’ movements. Perceptual and Motor Skills, 87, 1043-1056.
25.
Nishihara, K., Horiuchi, S., Eto, H., & Uchida, S. ( 2000). Mothers’ wakefulness at night in the post-partum period is related to their infants’ circadian sleep-wake rhythm. Psychiatry and Clinical Neurosciences, 54, 305-306.
26.
Nishihara, K., Horiuchi, S., Eto, H., & Uchida, S. ( 2002). The development of infants’ circadian rest-activity rhythm and mothers’ rhythm. Physiology and Behavior , 77, 91-98.
27.
Parry, B.L., Martinez, L.F., Maurer, E.L., Lopez, A.M., Sorenson, D., & Meliska, C.J. ( 2006). Sleep, rhythms and women’s mood. Part I. Menstrual cycle, pregnancy and postpartum. Sleep Medicine Reviews, 10, 129-144.
28.
Posmontier, B. ( 2008). Sleep quality in women with and without postpartum depression . Journal of Obstetric Gynecologic and Neonatal Nursing, 37, 722-735; quiz 735-727.
29.
Reppert, S.M., Weaver, D.R., & Rivkees, S.A. ( 1988). Maternal communication of circadian phase to the developing mammal. Psychoneuroendocrinology, 13, 63-78.
30.
Rogers, A.E., Caruso, C.C., & Aldrich, M.S. ( 1993). Reliability of sleep diaries for assessment of sleep/wake patterns. Nursing Research, 42, 368-372.
31.
Sadeh, A. ( 1996). Evaluating night wakings in sleep-disturbed infants: A methodological study of parental reports and actigraphy. Sleep, 19, 757-762.
32.
Sadeh, A. ( 2004). A brief screening questionnaire for infant sleep problems: Validation and findings for an Internet sample. Pediatrics , 113, e570-e577.
33.
Sander, L.W. ( 1977). The regulation of exchange in the infant care-giver systems . In M. Levins & L. Rosenblum (Eds.), Interaction and conversation and development of language. New York, NY: John Wiley.
34.
Sander, L.W., Julia, H.L., Stechler, G., & Burns, P. ( 1972). Continuous 24-hr interactional monitoring in infants reared in two care-taking environments. Psychosomatic Medicine , 34, 270-282.
35.
Sander, L.W., Stechler, G., Burns, P., & Julia, H. ( 1970). Early mother-infant interaction and 24-hour patterns of activity and sleep. Journal of the American Academy of Child Psychiatry, 9, 103-123.
36.
Seron-Ferre, M., Torres-Farfan, C., Forcelledo, M.L., & Valenzuela, G.J. (2001). The development of circadian rhythms in the fetus and neonate. Seminars in Perinatology , 25, 363-370.
37.
Shimada, M., Takahashi, K., Segawa, M., Higurashi, M., Samejim, M., & Horiuchi, K. ( 1999). Emerging and entraining patterns of the sleep-wake rhythm in preterm and term infants. Brain Development, 21, 468-473.
38.
Swaab, D.F., Hofman, M.A., & Honnebier, M.B. (1990). Development of vasopressin neurons in the human suprachiasmatic nucleus in relation to birth. Brain Research. Developmental Brain Research, 52, 289-293.
39.
Thomas, K.A., & Burr, R. ( 2002). Preterm infant temperature circadian rhythm: Possible effect of parental cosleeping. Biological Research for Nursing , 3, 150-159.
40.
Thomas, K.A., & Burr, R. ( 2008). Circadian research in mothers and infants: How many days of actigraphy data are needed to fit cosinor parameters? Journal of Nursing Measurement, 16, 201-206.
41.
Touchette, E., Petit, D., Paquet, J., Boivin, M., Japel, C., Tremblay, R.E., & Montplaisir, J.Y. (2005). Factors associated with fragmented sleep at night across early childhood. Archive of Pediatrics and Adolescent Medicine, 159, 242-249.
42.
Tsai, S.Y., Burr, R.L., & Thomas, K.A. ( 2009). Effect of external motion on correspondence between infant actigraphy and maternal diary. Infant Behavior and Development , 32, 340-343.
43.
Wulff, K., Dedek, A., & Siegmund, R. ( 2001). Circadian and ultradian time patterns in human behavior: Part 2: Social synchronisation during the development of the infant’s diurnal activity-rest pattern. Biological Rhythm Research , 32, 529-546.
44.
Zuckerman, B., Stevenson, J., & Bailey, V. ( 1987). Sleep problems in early childhood: Continuities, predictive factors, and behavioral correlates. Pediatrics, 80, 664-671.
