Autores: R. Peter Hobson, Matthew P.H. Patrick, Lisa E. Crandell, Rosa M. García Pérez and Anthony Lee.
Developmental Psychopathology Research Unit, Tavistock Clinic and University College, London, UK
Background and method: The aim of this study was to examine whether a mother’s sensitivity towards her one-year-old infant is related to the infant’s propensity to engage in triadic relations – that is, to orientate to an adult’s engagement with objects and events in the world, for example in sharing experiences with an adult. In order to determine that any effects were specific to infants behaviour in the interpersonal domain, we also tested their performance on tests of understanding means–ends relations and object permanence.
Results: The results were that high maternal sensitivity and low intrusiveness correlated with high levels of infant triadic interpersonal engagement with a stranger vis-à-vis performance on the non-social tasks. There was also suggestive evidence that maternal sensitivity might be related to infants propensity to share experiences with the mother. Exploratory analyses revealed that these findings held up when the effects of maternal socio-economic status and ethnic group were taken into account; and there was some indication that the effects of maternal intrusiveness on infant profiles of performance were more marked for mothers who did not have a partner.
Conclusion: There is a specific relation between maternal sensitivity and one-year-old infants propensity to engage with someone else in relation to the world.
Keywords: Attention, communication, infancy, joint attention, mothers, non-verbal communication, secondary intersubjectivity, triadic relations.
Towards the end of the first year of life, infants manifest new patterns of communication with other people. Trevarthen (e.g., Trevarthen & Hubley, 1978) was one of the first to describe this transition, which he characterised as a development from primary to secondary intersubjectivity. It involves a shift from the infant’s one-to-one engagement either with objects and events in the environment, or with another person, to a triadic pattern of communication in which the infant relates to another person in relation to an object or event (Adamson, 1995; Bakeman & Adamson, 1984).
A number of authors consider such communication to have great developmental significance, not only as a stepping-stone to more elaborate forms of social interchange, but also as critical for the emergence of symbolic functioning and language (e.g., Baldwin, 1995; Bruner, 1983; Hobson, 1993; Tomasello, 1999).
Towards the end of the 1970s, there were several attempts to catalogue the forms of interpersonal behaviour and communicative transaction that characterise this newfound ability for triadic relations (e.g., Bates, Benigni, Bretherton, Camaioni, & Volterra, 1979; Bretherton, McNew, & BeeghlySmith, 1981; Trevarthen & Hubley, 1978).
The list includes the infant’s capacity to follow the eye-gaze or point of another person, to request help and respond to simple verbal requests by others, to indicate or show objects to others (often looking to the other person’s eyes, to check whether he or she is attending), to initiate as well as accept invitations to play games such as peek-a-boo, to shake the head to express refusal, to imitate conventional gestures (e.g., hugging) and actions with objects, to utter greetings (Hi!) and name-like words, and to pretend to carry out adult activities such as using the telephone.
Carpenter, Nagell, and Tomasello (1998) examined the degree to which several of these kinds of behaviour emerged concurrently or in an ordered sequence in the development of individual infants. In observations of 24 infants at each month between 9 and 15 months of age, these investigators measured joint attentional engagement, gaze and point following, imitation, imperative and declarative gestures, and the comprehension and production of language.
They reported that infants progressed from sharing to following to directing others attention and behaviour.
At 12 months of age, for example, when all infants had been showing joint engagement for at least three months, 23 of the 24 infants showed proximal declarative gestures (showing/giving), 17 followed a point, 11 followed gaze, and 9 showed imperative gestures (Carpenter et al., 1998, figures 3 and 6, pp. 53 and 59, respectively).
At this same age, 14 out of the 24 infants passed a test of object permanence (figure 8, p. 62).
There is very little evidence from the study of typically developing infants to suggest which developmental mechanisms are responsible for the emergence of triadic interpersonal relations at the end of the first year, or which factors may affect this development. Striano and Rochat (1999) videotaped 7-month-old and 10-month-old infants in a) a dyadic situation in which free play between the infant and a female stranger was followed by a still-face period and then another phase of natural play, and in relation to which the authors assessed the infants initiations to re-engage the experimenter, and b) triadic settings of play in which infants were assessed for joint engagement (looking from an object to the experimenter and back to the object), their ability to localise a target by following another person’s gaze and/or point, and looking to the experimenter when the latter covered the infant’s hands holding a toy (blocking) or when teased.
The principal finding was that across the groups, infants scores out of three for each kind of re-engagement behaviour – smiling, re-engagement activity and reengagement vocalisation – were significantly correlated with total scores in triadic interaction. The authors also stated that the number of social initiatives during the first normal dyadic interaction was not correlated with the number of triadic behaviours, and from this they concluded that the results could not be explained by infants relative sociability.
Therefore this preliminary study of individual differences provides suggestive evidence of a link between an infant’s active engagement with a stranger in a one-to-one exchange, and triadic forms of interaction with an unfamiliar person. If such a link exists, then questions arise about the sources of infant individual differences.
Broadly speaking, one might begin by distinguishing between the effects of infant constitutional factors on the one hand, and environmental and especially social influences on the development of dyadic and triadic forms of interpersonal relatedness on the other – and of course, interactions among these factors.
In addition, one might consider factors that promote or hinder the emergence of infant–adult-world relations towards the end of infancy, and perhaps as a partly separate matter (our focus in this paper), factors that increase or lessen an infant’s propensity to engage in such relations with others, once they have the ability to do so.