The development of locomotor coordination: longitudinal change and invariance

Developmental sequence, relative timing, center of gravity, and phase-plane analyses were used to study a minimum of 15 years of longitudinal, filmed data on the development of hopping in 7 children. The developmental sequences revealed common, qualitative changes in the movement of the children, although each child progressed through the changes at his/her own rate. The timing analyses showed that, in the advanced hop, the tightest limb relationships were found within the hopping leg, then between contralateral limbs of the same girdle, and then between legs and arms. Relative-timing calculations revealed (a) intralimb, timing invariances that were present in first attempts to perform the skill at age 3 and remained for 15 years across all developmental levels; (b) emergent, interlimb timings that gradually became invariant; and (c) intra- and interlimb timing showing gradual development over the 15 years. One invariant, the time between landing and deepest knee flexion, is also invariant in the walk and the run (Shapiro, Zernicke, Gregor, & Diestel, 1981). Phase plane analyses indicated that the timing of peak and zero velocities may be the coordinative constant accounting for a relative timing invariance between the two legs. Position of the body's center of gravity may explain the invariant relative time between landing and deepest knee flexion, or the explanation could lie in the "equation of constraint" regulating joint equilibrium points. The data suggest that modeling the developing hop as the evolving interaction of four vibratory systems would be promising.     

Specific forms of facial EMG response index emotions during an interview: from Darwin to the continuous flow hypothesis affect-laden information processing

Previous research has demonstrated that mild negative emotional imagery and unpleasant sensory stimuli lead to greater electromyographic activity over the brow muscle region than mild positive imagery and stimuli, even in the absence of significant changes in visceral and general facial EMG activity. Previous research has not addressed whether electromyographic responses over the brow region are a sensitive and specific index of emotions, however, since a multiplicity of events lead to changes in brow activity. In this research, facial electromyographic and audiovisual recordings were obtained while individuals were interviewed about themselves. Afterwards, individuals were asked to describe what they had been thinking of during specific segments of the interview marked by distinctive electromyographic responses over the brow region in the context of ongoing but stable levels of activity elsewhere in the face. The results are interpreted in terms of a continuous flow hypothesis of affect-laden information processing.     

Impressions of people created by age-related qualities of their gaits

Drawing on the ecological theory of social perception, we investigated the impact of age-related gait qualities on trait impressions. In Study 1, subjects observed 5- to 70-year-old walkers depicted in point-light displays, and rated the walkers' traits, gaits, and ages. Younger walkers were perceived as more powerful and happier than older walkers. A composite of youthful gait qualities predicted trait impressions regardless of the walkers' masculine gait qualities, sex, and perceived age. In Study 2, subjects observed young adult walkers depicted in point-light displays and rated their traits, gaits, and ages. Consistent with the effects of real age found in Study 1, young adults with youthful gaits were perceived as more powerful and happier than peers with older gaits, irrespective of their masculine gait qualities, sex, and perceived age. Study 3 replicated Study 2 using displays showing walkers' full bodies and faces. A youthful gait predicted trait impressions even when subjects could discern the walkers' age and sex.     

Shared knowledge about infants among fathers and mothers

Evidence for the exchange of parenting information between low-income White mothers and fathers of infants was found. Mothers had more accurate expectations for normative development than fathers, but more accurate fathers had spouses who were also more accurate--even when education was controlled. Though few significant differences were evident in help-seeking behavior when infant problems were encountered, fathers turned to fewer helpers than mothers and were somewhat more likely to rely solely on their spouse. These data indicate that researchers must consider the exchange of information between spouses, particularly when studying the socialization of parenting among fathers at this stage in the life cycle of the family.     

Effects of a structured behavior modification treatment program on locus of control in behaviorally disturbed children

The effect of a 10-day behavior modification treatment program on locus of control was investigated. The subjects were children (N = 130; 6 to 12 years old) with severe behavioral disorders who were predominantly from low socioeconomic backgrounds, from broken homes, and socially deprived. Pre- and post-testing was done with the Nowicki-Strickland Preschool and Primary Internal-External Control Scale (Nowicki & Duke, 1974) and the Nowicki-Strickland Locus of Control Scale for Children (Nowicki & Strickland, 1973). Children between the ages of 10 and 12 responded to therapy with a significant increase in internality, but younger children did not.     

Marital conflict and adjustment: speech nonfluencies in intimate disclosure

Speech nonfluency in response to questions about the marital relationship was used to assess anxiety. Subjects were 31 husbands and 31 wives, all white, college educated, from middle- to lower-middle-class families, and ranging from 20 to 30 years of age. Three types of nonfluencies were coded: filled pauses, unfilled pauses, and repetitions. Speech-disturbance ratios were computed by dividing the sum of speech nonfluencies by the total words spoken. The results support the notion that some issues within marriage are more sensitive and/or problematic than others, and that, in an interview situation, gender interacts with question content in the production of nonfluencies.     

Finding the face in the crowd: an anger superiority effect

Facial gestures have been given an increasingly critical role in models of emotion. The biological significance of interindividual transmission of emotional signals is a pivotal assumption for placing the face in a central position in these models. This assumption invited a logical corollary, examined in this article: Face-processing should be highly efficient. Three experiments documented an asymmetry in the processing of emotionally discrepant faces embedded in crowds. The results suggested that threatening faces pop out of crowds, perhaps as a result of a preattentive, parallel search for signals of direct threat.     

Perceptual sensitivity to dimensional and similarity relations in free and rule-governed classifications

Two experiments were conducted to investigate the perceptual primacy of dimensional and similarity relations in the stimulus classifications of younger and older subjects. In Experiment 1, 4- and 10-year-olds were given free classifications in which they could group stimuli according to overall similarity or identities in size, color, or orientation. Both age groups classified stimuli most frequently according to identities on separate dimensions. In Experiment 2, 4-year-olds and adults were given free classifications followed by rule-governed classifications which required them to group stimuli according to specific relations. In the free classifications, a majority of subjects in both age groups classified the stimuli most frequently according to identities on separate dimensions. In the rule-governed classifications, both age groups were more accurate when a single separate relation was required for solution than when overall similarity was required. These results support a differential-sensitivity view of perceptual development, which asserts that individuals at all ages primarily perceive and use separate relations.