Investigated effects of changes in temporal organization of material play participation upon variety of infant and maternal social interactive variables. Results confirmed hypothesis that both three- and five-month-old infants recognize temporal changes and respond differentially to natural, slower, and faster temporal styles. (Author/MP)

Analyzes methods used to record infant head position and the limits of these methods. An experimental device is proposed which records infant head turning and head righting when the vestibular system is stimulated. (Author/DB)

One- and two-month-old infants were shown schematic drawings of a human face with features arranged (1) naturally, (2) symmetrically but scrambled, and (3) asymmetrically and scrambled. Two-month-olds discriminated among all arangements and preferred the natural arrangement; one-month-olds showed no discrimination or preference. (Author/DB)

A sample of eight 19-month-old toddlers were observed during free play at home, with and without a familiar toddler playmate. With the peer present, there was significantly more high-level play with toys and less low-level play with toys than with the peer absent. (Author/JH)

Two experiments examined the effects of changes in adult eye direction during both televised and live contingent interaction with infants 3 to 6 months of age. Infants' smiling declined whenever adults looked away, supporting the hypothesis that infants express their cognitive appreciation of the adults' eye direction by their affective behavior.…

Three studies examined the tongue protrusion (TP) behaviors of young infants in response to visual stimuli. Infants produced TPs in response to objects within reach before but not after the onset of reaching behavior. The results suggest that infants' TPs in response to a tongue-protruding adult reflect very early attempts at oral exploration of…

Used signal detection methodology to examine how cognitive set affects mothers' response to crying by "difficult" and "easy" infants. Found that increased mothers' sensitivity was associated with the "difficult" infant cognitive set and that mothers with high illusory control were least sensitive in detecting…

Conducted spectrum analysis of standard and vociferous cries from infants with Wessel's colic, non-Wessel's colic, and comparison infants. Vociferous cries had longer duration, higher fundamental frequency, and greater percentage of dysphonation than standard cries. After feedings, problematic criers had greater percentage of dysphonation in…

Used a habituation-dishabituation procedure to test ability of 4-, 5-, and 7-month-olds to differentiate between a subjective ellipse and a nonsubjective pattern that were constructed by displacing the inducing elements of the illusory figure. Found that even 4-month-olds discriminated between the subjective ellipse and nonillusory display. This…

Examined the sex differences in physiological and behavioral stress reactivity among 36 healthy, full-term neonates after a mildly stressful behavioral assessment procedure. Salivary cortisol, heart rate change, Neonatal Behavior Assessment Scale (NBAS) cluster scores, and behavioral states after the NBAS provided 100% discrimination between male…

Investigated the possibility that previous reports of a relation between locomotor status and stage-4 object permanence performance could be generalized to performance on an object localization task. Findings suggest that the effects of locomotor experience on infants' search performance are quite specific and mediated by a variety of factors that…

Infants participated in a nonsocial contingency task immediately after a social interaction with their mothers. The amount of time mothers and infants spent in a state of vocal turn-taking predicted individual differences in infants' subsequent performance on the contingency task. (PCB)

Measures of positive and negative affect and affect ability; of look, approach, and proximity behavior; and of overall response pattern were obtained from 66 infants of 12 months. These measures and other results suggested that both parents are significant sources of emotional guidance for infants in conditions of uncertainty. (RH)

Studied head position preference in 20 newborns differing by Cesarean or vaginal delivery and sex. Found that neither factor accounted for differences. The head turned right more often and was maintained longer in this position during quiet wakefulness, regardless of scoring method. When using global scoring, duration of midline position was…