The development of maternal touch across the first year of life

Abstract

The developmental trajectories of specific forms of maternal touch during natural caregiving were examined across the first year in relation to the development of mother–infant reciprocal communication. One hundred and thirty-one mothers and infants in four groups aged 3, 6, 9, and 12 months were observed in a cross-sectional design at home during natural caregiving and mother–child play sessions. Microanalytic coding of the caregiving sessions considered nine forms of maternal touch, which were aggregated into three global touch categories: affectionate, stimulating, and instrumental. Play sessions were coded for maternal sensitivity and dyadic reciprocity. Maternal affectionate and stimulating touch decreased significantly during the second 6 months of life. In parallel, dyadic reciprocity increased in the second half year. Dyadic reciprocity was predicted by the frequency of affectionate touch but not by any other form of touch. Results contribute to specifying the role of touch as it evolves across the first year of life within the global mother–infant communication system.

Introduction

Touch is a multi-dimensional phenomenon that includes various sub-types, each of which may affect infant development in a unique way, especially during the first months of life. For instance, higher levels of maternal affectionate touch in early infancy were found to predict cognitive and neurobehavioral development [1], [2], better maternal adaptation to the mothering role [3], and an increase in infant smiles and vocalizations [4]. On the other hand, higher levels of stimulating touch elicited more negative facial expressions compared with stroking and holding [5], [6]. Mothers tend to use different forms of touch as a result of infant cues and temperamental dispositions [7], cultural background [8], or in situations where the typical pattern of mother–infant relatedness is disrupted, such as during the still-face paradigm.

Individual differences in maternal well-being are also expressed through the frequency and type of maternal touch. For example, depressed mothers tend to use less affectionate touch and more stimulating touch [1], [9], [10], [11], [12]. Due to the fact that touch is sensitive to both maternal and infant contributions, it is possible that different forms of maternal touch may have unique effects at different stages of development and thus, the development of specific forms of maternal touch and their role within the mother–infant normal relational system should be investigated across infancy [13].

Previous studies of maternal touch typically differentiated various forms of touch using global constructs, such as harsh or negative touch versus affectionate touch (i.e., caressing, holding, and light stroking versus harsh, awkward and forcing; [14]). More detailed inventories of touch subcategories include proprioceptive touch, vestibular touch, passive touch, instrumental touch, and firm touch [15], [16], [9], [11], [17], [18]. In combination, the various forms of positive maternal touch types may be grouped into three central subcategories: affectionate touch, stimulating touch, and instrumental touch. Each of these sub-types has been used in at least one of the aforementioned studies to differentiate healthy from at-risk dyads.

Studies of maternal touch in typically-developing infants have mainly focused on the first months of life (e.g. [19]). In contrast, studies of touch at older ages concentrated on pathological populations, such as children with feeding disorders or failure to thrive [16], [29], [15]. As both the frequency and quality of maternal touch in primates show substantial variations with development [20], it is important to examine the development of maternal spontaneous touch at different nodes across infancy in the normal human mother.

Maternal touch is part of the global mother–infant communicative system and is related to the level of maternal sensitivity and the degree of reciprocity and synchrony between mother and child. Reciprocity considers the degree of give and take between the mother and the child during the interaction and synchrony describes the temporal coordination between the behaviors of the mother and the child [21], [22], [23]. Reciprocity and synchrony develop across the first year of life [24], [25], [26], [27] and reflect the degree of familiarity mother and child have of each other's patterns and rhythms [29]. Reciprocity tends to develop across the first year of life whereas the degree of maternal sensitivity often remains constant, as sensitivity implies the mother's careful adaptation to the child's changing, age-appropriate signals and emerging capacities [29], [30], [31], [32]. However, the associations between various forms of maternal spontaneous touch during basic caregiving and the level of dyadic reciprocity at play across the first year of life have not yet been addressed. Because the mother's touch may evolve with time and its interactive meaning may change with development, it is important to chart how the three forms of maternal touch – affectionate, instrumental, and stimulating – interact with the give-and-take reciprocity between mother and child at different stages across the first year. Furthermore, charting the development of maternal touch across the first year in a normative sample may serve as a basis for understanding high-risk development. As such, the goal of this study was to provide normative data on the development of specific forms of maternal touch, focusing on concrete micro-level touch patterns during mother–infant interactions rather than on ecological factors such as maternal breastfeeding or infant temperament. Reciprocity and synchrony are among the most important components of the early caregiving environment and carry long-term effects on infant growth [25], and were thus chosen as the outcome variables.

In light of the above, the goals of the present study were twofold: (1) to examine developmental changes in maternal touch across the first year and (2) to address the role of touch categories in shaping the reciprocity between mother and infant, controlling for demographic maternal and infant variables that are known to affect the level of interactive synchrony. On the basis of previous research, we hypothesized that affectionate touch would be the most growth-promoting form of touch and would have the closest relations to mother–infant reciprocity as compared to all other forms of touch. Reciprocity was selected as an outcome variable due to the reported links between mother–infant reciprocity with the child's cognitive, linguistic and social–emotional outcomes [33], [34].