Why do we hunger for touch? The impact of daily gentle touch stimulation on maternal-infant physiological and behavioral regulation and resilience.

We report the impact of a Gentle Touch Stimulation (GTS) program. Forty-three mothers provided daily 10-min GTS with C-tactile (CT) afferent optimal stroking touch, for 4 weeks to their 3-12 weeks old infants. CT-afferents are cutaneous unmyelinated, low-threshold mechanosensitive nerves hypothesized to underly the regulatory impact of affective touch. We compared physiological and behavioral responses during a no-touch-baseline (BL), static-touch-baseline (BL-T), intervention/control (GTS/CTRL), Still Face (SF) and Reunion (RU) condition for GTS-infants versus a control-group (CTRL) at the start (T1) and end of (T2) of the program. We collected mother-infant ECG, respiration, cortisol, video-recordings, and diary-reports. At T1, physiological arousal significantly increased during SF in both groups, that is, decreased respiratory sinus arrhythmia (RSA) and R-R interval (RRI). At T2, GTS-infants showed significantly increased RSA, RRI, decreased respiration during GTS, buffering SF-arousal and allowing complete recovery during RU; CTRL-infants showed higher SF-arousal and small recovery, under initial BL-levels. Maternal cardio-respiratory showed a metabolic investment during RU. Cortisol and behavioral analyses showed higher arousal in CTRL-infants than GTS-infants at T2. We suggest that the combination of phasic short-term and tonic long-term responses to CT-optimal stroking touch, delivered in a structured daily manner, contribute to the building of infant stress regulation and resilience.

我们报告了轻柔触摸刺激（GTS）项目的影响。43位母亲每天对她们3 - 12周大的婴儿进行10分钟的轻柔触摸刺激，采用C -触觉（CT）传入神经最佳的轻抚触摸方式，持续4周。C -触觉传入神经是皮肤无髓鞘、低阈值的机械敏感神经，据推测是情感性触摸调节作用的基础。我们比较了在无触摸基线（BL）、静态触摸基线（BL - T）、干预/对照（GTS/CTRL）、静止脸（SF）和重聚（RU）条件下，GTS婴儿组与对照组（CTRL）在项目开始（T1）和结束（T2）时的生理和行为反应。我们收集了母婴的心电、呼吸、皮质醇数据，进行了视频记录以及日记报告。在T1时，两组在静止脸阶段的生理唤醒都显著增加，即呼吸性窦性心律不齐（RSA）减少和R - R间期（RRI）缩短。在T2时，GTS婴儿组显示出RSA显著增加、RRI增加，在GTS过程中呼吸减缓，缓冲了静止脸阶段的唤醒，并在重聚阶段完全恢复；对照组婴儿在静止脸阶段唤醒程度更高，恢复程度小，仅恢复到初始基线水平。母亲的心肺功能在重聚阶段显示出代谢投入。皮质醇和行为分析表明，在T2时对照组婴儿比GTS婴儿的唤醒程度更高。我们认为，以结构化的日常方式给予的对C -触觉最佳轻抚触摸的阶段性短期和持续性长期反应相结合，有助于婴儿压力调节和适应能力的建立。