Page 47 - Designing Sociable Robots

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28 Chapter 3

through attentive regard, a “softening” of their face and eyes, and a prolonged suppression
of body movement. More significantly, however, humans respond contingently to an in-
fant’s own actions. Caregivers, in particular, frequently respond to an infant’s immediately
preceding actions. As a result, the infant is particularly responsive to his caregiver, and the
caregiver is particularly good at acquiring and sustaining her infant’s attention. According
to Newson, “this simple contingent reactivity makes her an object of absolute, compelling
interest to her baby” (Newson, 1979, p. 208).
Not only are infants born with a predisposition to respond to human social stimuli,
they also seem biologically primed to respond in a recognizable social manner (Trevarthen,
1979). Namely, infants are born with a set of well-coordinated proto-social responses which
allowthemtoattractandengageadultsinrichsocialexchanges.Forinstance,Johnson(1993)
1
argues that the combination of having a limited depth of field with early fixation patterns
forces the infant to look predominantly at his caregiver’s face. This brings the infant into
face-to-face contact with his caregiver, which encourages her to try to engage him socially.
Trevarthen (1979) discusses how infants make prespeech movements with their lips and
tongue,givesthemtheappearanceoftryingtorespondwithspeech-likesounds.Kaye(1979)
discusses a scenario where the burst-pause-burst pattern in suckling behavior, coupled with
the caregiver’s tendency to jiggle the infant during the pauses, lays the foundation of the
earliest forms of turn-taking that becomes more flexible and regular over time. This leads
to more fluid exchanges with the caregiver while also allowing her to add structure to her
teaching scenarios with him. It is posited that infants engage their caregivers in imitative
exchanges, such as mirroring facial expressions (Meltzoff & Moore, 1977) or the pitch and
duration of sounds (Maratos, 1973). Trevarthen (1979) discusses how the wide variety of
facial expressions displayed by infants are interpreted by the caregiver as indications of the
infant’s motivational state. They serve as his responses to her efforts to engage him, and
she uses them as feedback to carry the “dialogue” along.
Together, the infant’s biological attraction to human-mediated events in conjunction with
his proto-social responses serve to launch him into social interactions with his caregiver.
There is an imbalance, however, in the social and cultural sophistication of the two partners.
Fortunately, there are a number of ways in which an infant limits the complexity of his
interactions with the world. This is a critical skill for social learning because it allows the
infant to keep himself from being overwhelmed or under-stimulated for prolonged periods
of time. Tronick et al. (1979) note that this mismatch is critical for the infant’s development
because it provides more and more complicated events to learn about. Generally speaking,

1. A newborn’s resolution is restricted to objects approximately 20 cm away, about the distance to his caregiver’s
face when she holds him.