Television Exposure and Children's Decoding of Nonverbal Behavior1

Two studies considered the way in which the magnitude of exposure to television relates to children's understanding and interpretation of others' nonverbal behavior. In the first study, 6th graders made judgments regarding other children whose nonverbal facial behavior did not match their internal emotional state. Results showed that heavier television viewers held a less differentiated, more simplistic view of the consequences of nonverbal self-presentation strategies. In the second study, children in Grades 2 through 6 made judgments of others' nonverbal expressions of emotion. As predicted, heavier television viewers were better at decoding others' nonverbal expressions than lighter viewers, presumably because of their greater exposure to nonverbal displays of emotion on television. In addition, nonverbal decoding skills improved with age.     

Control of Trajectory Modifications in Target-Directed Reaching

Human reaching movements to fixed and displaced visual targets were recorded and compared with simulated movements generated by using a two-joint arm model based on the equilibrium-point (EP) hypothesis (lambda model) of motor control (Feldman, 1986). The aim was to investigate the form of central control signals underlying these movements. According to this hypothesis, movements result from changes in control variables that shift the equilibrium position (EP) of the arm. At any time, muscle activations and forces will depend on the difference between the arm's EP and its actual position and on the limb's velocity. In this article, we suggest that the direction of EP shift in reaching is specified at the hand level, whereas the rate of EP shift may be specified at the hand or joint level. A common mechanism underlying reaching to fixed and displaced targets is proposed whereby the EP of the hand shifts in a straight line toward the present target. After the target is displaced, the direction of the hand EP shift is modified toward the second target. The results suggest that the rate of shift of the hand EP may be modified for movements in different parts of the work space. The model, with control signals that vary in a simple fashion over time, is able to generate the kinematic patterns observed empirically.     

PARENT EDUCATION PROJECT III: INCREASING AFFECTION AND RESPONSIVITY IN DEVELOPMENTALLY HANDICAPPED MOTHERS: COMPONENT ANALYSIS,GENERALIZATION, AND EFFECTS ON CHILD LANGUAGE

We evaluated the effects of a parent training program consisting of verbal instruction, modeling, and feedback on the affection and responsivity of 3 developmentally handicapped mothers towards their children. The results indicated the following: First, the training package increased maternal physical affection, praise, and imitation of child vocalizations. These parenting skills increased to levels found in comparison groups of nonhandicapped mothers. Second, the training package was more effective than verbal instruction alone, the latter being the predominant method presently used by social service workers. Third, most maternal gains were maintained over a 3- to 18-month follow-up period, although one mother required a reinforced maintenance procedure. Fourth, instructing mothers to generalize served to increase the generalization of newly acquired skills from play times (the training context) to child-care tasks (e.g., diapering, feeding). Fifth, teaching the parents to imitate child vocalizations was related to gains in both the frequency and quality of verbal behavior of the two language delayed children as measured by standardized developmental tests and in vivo comparisons with age-matched children (who had nonhandicapped parents). These results show that behavioral instruction can improve important child-rearing skills of developmentally handicapped mothers, with corresponding benefits to their children.     

Relations among regular and irregular morphologically related words in the lexicon as revealed by repetition priming

Several experiments examined repetition priming among morphologically related words as a tool to study lexical organization. The first experiment replicated a finding by Stanners, Neiser, Hernon, and Hall (Journal of Verbal Learning and Verbal Behavior, 1979,18, 399-412), that whereas inflected words prime their unaffixed morphological relatives as effectively as do the unaffixed forms themselves, derived words are effective, but weaker, primes. The experiment also suggested, however, that this difference in priming may have an episodic origin relating to the less formal similarity of derived than of inflected words to unaffixed morphological relatives. A second experiment reduced episodic contributions to priming and found equally effective priming of unaffixed words by themselves, by inflected relatives, and by derived relatives. Two additional experiments found strong priming among relatives sharing the spelling and pronunciation of the unaffixed stem morpheme, sharing spelling alone, or sharing neither formal property exactly. Overall, results with auditory and visual presentations were similar. Interpretations that repetition priming reflects either repeated access to a common lexical entry or associative semantic priming are both rejected in favor of a lexical organization in which components of a word (e.g., a stem morpheme) may be shared among distinct words without the words themselves, in any sense, sharing a “lexical entry.”     

Touch attenuates infants’ physiological reactivity to stress

Animal studies demonstrate that maternal touch and contact regulate infant stress, and handling during periods of maternal deprivation attenuates the stress response. To measure the effects of touch on infant stress reactivity during simulated maternal deprivation, 53 dyads were tested in two paradigms: still‐face (SF) and still‐face with maternal touch (SF+T). Maternal and infant cortisol levels were sampled at baseline, reactivity, and recovery and mother’s and infant’s cardiac vagal tone were measured during the free play, still‐face, and reunion episodes of the procedure. Cortisol reactivity was higher among infants in the SF condition and while cortisol decreased at recovery for infants in the SF+T, it further increased for those in the SF. Vagal tone showed a greater suppression when SF was not accompanied by maternal touch. Touch synchrony during free play was associated with higher infant vagal tone, whereas touch myssynchrony – maternal tactile stimulation while the infant gaze averts – correlated with higher maternal and infant cortisol. In humans, as in mammals, the provision of touch during moments of maternal unavailability reduces infants’ physiological reactivity to stress.