Generalized imitation within three response classes in typically developing infants

Effects of modeling and contingent praise on infant imitation of three different responses was analyzed. Generalization to nonreinforced probe models was assessed both within and across response types. Three 12- to 14-month-old infants and their mothers participated in this study. During baseline the mothers provided models only. During treatment mothers modeled and also praised contingent upon infant matching of the training models. During interspersed probe trials the mothers modeled different responses, which, if matched by the infant, produced no praise. The three responses modeled were motor-with-toy, motor-without-toy, and vocal responses. The dependent measure was the percentage of maternal models that were matched by the infant within 6 s. Nonmatching responses of the same response type were also measured. Results showed a systematic increase in the percentages of training and probe models matched by the three infants following the introduction of the model-and-praise treatment condition. Nonmatching responses did not systematically increase. Thus, imitation generalized within response class, but not across response classes.     

Preventing Contagion With Avian Influenza: Disease Salience,Attitudes Toward Foreigners,and Avoidance Beliefs1

Building on an evolutionary approach to out‐group avoidance, this study showed relations between perceived disease salience and beliefs in the efficacy of avoiding foreigners as protective measures in the context of a real‐life pandemic risk; i.e., avian influenza. People for whom avian influenza was salient and who held unfavorable attitudes toward foreigners were more likely to believe that avoiding contact with foreigners protects against infection. This finding suggests that individual differences in social attitudes moderate evolved mechanisms relating threat of disease to out‐group avoidance.     

The infant vocal-conditioning literature: a theoretical and methodological critique

Most studies of operant conditioning of infant vocalization do not fully use the experimental-analysis-of-behavior methodology that behavioral researchers have developed to study operant phenomena. This could be a contributing factor in their failure to correctly operationalize the definition of reinforcement, severely limiting the amount of information they can provide about operant learning in infants. Furthermore, single-subject-design studies may be added to supplement or replace group experimental designs in the study of infant vocal conditioning if we are to recognize the different learning processes that affect infant learning. Finally, single-subject experimental designs may be crucial to the development of an effective technology of early language intervention.     

Differential reinforcement of other-than-vocalization as a control procedure in the conditioning of infant vocalization rate

The purpose of the present study is to demonstrate reinforcement control over infant vocalization rates using a DRO schedule to control for elicitation of social stimulation. Mothers of four 2 1/2- to 3-month-old infants provided social reinforcement for their infants' vocalization under two schedules: continuous reinforcement (CRF) and differential reinforcement of other-than-vocalization (DRO). In a repeated-reversal single-subject experimental design, all four infants produced systematically higher vocalization rates during CRF, even though densities of social stimulation during DRO were equal to or greater than densities provided during CRF. Thus, whatever its elicitation value, social stimulation may reinforce infant vocalization rates.     

Effects of delayed reinforcement on infant vocalization rate.

Three previous studies have failed to demonstrate conditioning in infants using a 3-s delay of reinforcement. The effects of a delayed reinforcement schedule on vocalization rates therefore were explored in a single-subject repeated-reversal experimental design for 3 4- to 6-month-old normally developing infants. Each infant received delayed social reinforcement from his or her parent for vocalizing. The comparison condition was a schedule of differential reinforcement of behavior other than vocalizations to control for elicitation by social stimulation. An operant level of infant vocalizations was the initial condition, after which the differential reinforcement schedule was implemented in an across-subjects multiple baseline design. Infants' vocalization rates increased above levels measured during differential reinforcement following onset of the delayed reinforcement condition. Also, vocalization rates decreased during differential reinforcement compared to operant levels. The successful use of delayed reinforcement schedules with infants in this study, as opposed to others, is discussed in terms of procedural differences among them.     

Psychodynamic assessment of changes in children with autism under psychoanalytic treatment

In this article the authors report insights into autism developed through their extensive experience of psychoanalytic therapy with children with autism. The fi rst stages of body psychic development are seriously disrupted by this pathology, resulting in primitive anxieties of falling and of being liquefi ed. These anxieties are connected to the fragile development of body ego and of its related spatiotemporal organisation. The changes in children observed by the authors during the therapeutic process lead them to offer a psychodynamic assessment tool, which revolves principally around the development of body ego. After the initial state of 'severe autism', the authors describe three stages: the stage of 'recovery of the skin' (Bick); the established 'symbiotic phase', subdivided into 'vertical then horizontal splitting of the body ego'; and fi nally the stage of 'individuation'. First, the authors describe the principal psychoanalytic approaches to autism and refl ect on the links possible with nonpsychoanalytic work.