Contribution of circadian rhythm and maternal entrainment to infant regulation

描述（由申请人提供）：生理节律对于建立母亲和婴儿之间的互动同步至关重要，并且随后互动同步是婴儿调节发展的基础。很少有研究将发育中的婴儿昼夜节律和母亲夹带与母婴互动同步和随后的婴儿调节联系起来。喂养困难、睡眠-觉醒模式紊乱和母婴互动改变是失调婴儿的特征。本研究的目的是描述婴儿昼夜节律发展的轨迹，研究母亲和婴儿昼夜节律和相互作用的早期同步性，并根据节律和相互作用的同步性预测婴儿的调节。主要目标包括：（1）通过在婴儿4、8和12周龄时进行的体动记录的周期峰值相位、振幅和余弦拟合（R2）来确定母亲和婴儿昼夜节律定时和强度的纵向模式。(2)探索纵向环境的影响（光，家庭日常）夹带的昼夜节律测量的母亲和婴儿唾液褪黑激素昼夜节律评估在4，8，和12周的婴儿年龄。(3)检查母婴生理同步性的纵向模式，其定义为在婴儿4、8和12周龄时进行的体动记录中得出的母亲和婴儿昼夜节律（CR-CORR）参数（峰值相位、振幅和余弦拟合）之间的单独相关性。(4)评估（a）母婴间歇同步性（CO-ACT）的预测，通过在12周时协调凝视、发声和触摸的比例测量，以及（B）婴儿生理和情绪调节的预测，通过婴儿/幼儿症状检查表（ITSC）、实验室气质评估组合（Lab-TAB）和婴儿简易睡眠问卷（BISQ）在32周时测量，以母婴生理同步性（CR-CORR）为预测因子。将采用纵向设计研究40对健康母婴，测量时间为4、8、12和32周龄婴儿。在第4、8和12周，将在家中使用体动记录仪记录结合环境光的测量来确定活动的昼夜节律，并且将在24小时内连续收集唾液样品以评估褪黑激素节律。在12周时，将根据5分钟的母婴互动视频记录对面对面情感同步性（CO-ACT）进行编码。在32周时，将使用实验室气质评估组合（Lab-TAB）、婴儿/幼儿症状检查表（ITSC）和简明婴儿睡眠问卷（BISQ）评估婴儿调节能力，并将评估母体睡眠和觉醒障碍、抑郁和疲劳以及家庭常规。昼夜节律将从余弦分析得出。将对余弦参数（峰值相位、振幅、余弦拟合）进行关联（CR-CORR）。母婴生理同步（CR-CORR）将用于预测12周时的互动同步和32周时的婴儿调节。 公共卫生相关性：本研究将探讨母亲与婴儿的生理节律，并探讨母婴生理节律的同步性对母婴互动和婴儿调节的影响。将确定母亲和婴儿活动的昼夜节律和褪黑激素，并将其与互动期间的母亲和婴儿面对面行为以及与以后的婴儿情绪和行为调节相关联。理论上，母亲和婴儿身体活动的早期协调会影响婴儿的睡眠-觉醒模式以及行为和情绪反应。

DESCRIPTION (provided by applicant): Physiological rhythm is central to establishment of interactive synchrony between mothers and infants and subsequently interactive synchrony is the foundation for development of infant regulation. Few studies have associated developing infant circadian rhythm and maternal entrainment with maternal-infant interactive synchrony and subsequent infant regulation. Feeding difficulties, disrupted sleep-wake pattern, and altered maternal-infant interaction are characteristic of dysregulated infants. The purpose of the proposed research is to characterize the l trajectory of infant circadian rhythm development, examine early synchrony of maternal and infant circadian rhythm and interaction, and predict infant regulation based on rhythm and interactive synchrony. Primary Aims include: (1) Determine the longitudinal pattern of maternal and infant circadian rhythm timing and strength as measured by cycle acrophase, amplitude, and cosinor fit (R2) of actigraphy recordings performed at 4, 8, and 12 weeks infant age. (2) Explore longitudinally environmental influences (light, home routine) on entrainment of circadian rhythm as measured by maternal and infant salivary melatonin circadian rhythm assessed at 4, 8, and 12 weeks infant age. (3) Examine the longitudinal pattern of maternal- infant physiological synchrony defined as the separate correlations between mother and infant circadian rhythm (CR-CORR) parameters (acrophase, amplitude, and cosinor fit) derived from actigraphy recordings performed at 4, 8, and 12 weeks infant age. (4) Assess the prediction of (a) maternal-infant interactional synchrony (CO-ACT), as measured by proportion of coordinated gaze, vocalization, and touch at 12 weeks, and (b) infant physiological and emotional regulation as measured by Infant/Toddler Symptom Checklist (ITSC), Laboratory Temperament Assessment Battery (Lab-TAB), and Brief Infant Sleep Questionnaire (BISQ) at 32 weeks infant age, using maternal-infant physiological synchrony (CR-CORR) as predictor. Forty healthy mother-infant pairs will be studied using a longitudinal design with times of measure at 4, 8, 12, and 32 weeks infant age. At 4, 8, and 12 weeks circadian rhythm of activity will be determined in the home using actigraphy recordings, combined with measurement of environmental light, and salivary samples will be collected serially throughout a 24-hour day to assess melatonin rhythm. At 12 weeks face-to-face affect synchrony (CO-ACT) will be coded from a 5 minute video recording of mother-infant interaction. At 32 weeks infant regulation will be assessed using the Laboratory Temperament Assessment Battery (Lab-TAB), Infant/Toddler Symptom Checklist (ITSC), and Brief Infant Sleep Questionnaire (BISQ) and maternal sleep and wake disturbance, depression, and fatigue as well as home routine will be assessed. Circadian rhythm will be derived from cosinor analysis. Cosinor parameters (acrophase, amplitude, cosinor fit) will be correlated (CR-CORR). Maternal-infant physiological synchrony (CR-CORR) will be used to predict interactive synchrony at 12 weeks and infant regulation at 32 weeks. PUBLIC HEALTH RELEVANCE: This project involves circadian rhythm in mothers and their young infants and will examine the influence of synchrony between mother and infant physiological rhythms on maternal-infant interaction and infant regulation. Circadian rhythm of mother and infant activity and melatonin will be determined and correlated with mother and infant face-to-face behavior during interaction and with later infant emotional and behavioral regulation. Early coordination of mother and infant physical activity is theorized to affect infant sleep-wake pattern and behavioral and emotional responsiveness.