Effects of vestibular stimulation on motor development and stereotyped behavior of developmentally delayed children

Four developmentally delayed babies were given semicircular canal stimulation in an effort to facilitate their motor and reflex development. Each of the children also exhibited abnormal stereotyped movements. The theory was advanced that these movements are related to motor development and that significant improvements in motor abilities will produce changes in the intensity and/or form of stereotypic responding. Semicircular canal stimulation was provided by rotating the children in a motor-driven chair at a velocity of about 17 rpm for 10 minutes daily over a period of 2 weeks. Standard motor and reflex measures were taken before, during, and after the rotation treatment period. Daily observations were made of the children's stereotyped movements. Over the course of the study all of the children showed motor and/or reflex changes that were attributable to the vestibular stimulation. In addition, some evidence was obtained linking changes in stereotypic responding to the vestibular stimulation.This work was supported by PHS Grant Nos.HD15051 and HD13344.     

Observational studies of retarded children with multiple stereotyped movements

Stereotyped movements, such as body rocking and hand gesturing, are common among developmentally delayed children. However, very little is known concerning the naturally occurring circumstances that produce variability in this type of responding. Three relatively long-term observational studies, involving seven preschool children, each of whom exhibited multiple stereotypies, were conducted to determine the extent to which the type of activity or setting had any effect upon the rates of these responses. Repeated observations were made of each child during a variety of school activities. In two studies, adult-child interactions were also recorded. The results showed that, in general, the particular activity greatly affected rates of stereotyped behavior, although there were some marked individual differences. Moreover, in two studies variability was apparent across sessions within a particular setting. For some of the children, there was evidence that their multiple stereotypies were functionally interrelated. Adult interactions, as recorded in one study, appear to be both quantitatively and qualitatively different for stereotyping as contrasted with nonstereotyping children. An environmental analysis employing a sequential model indicated that there were teacher behaviors that affected the frequency and/or conditional probability of the child's aberrant behavior.This research was supported by P.H.S. Grant No. HD-00973.     

The development and flexibility of gaze alternations in bonobos and chimpanzees

Infants’ early gaze alternations are one of their first steps towards a sophisticated understanding of the social world. This ability, to gaze alternate between an object of interest and another individual also attending to that object, has been considered foundational to the development of many complex social‐cognitive abilities, such as theory of mind and language. However, to understand the evolution of these abilities, it is important to identify whether and how gaze alternations are used and develop in our closest living relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). Here, we evaluated the development of gaze alternations in a large, developmental sample of bonobos (N = 17) and chimpanzees (N = 35). To assess the flexibility of ape gaze alternations, we tested whether they produced gaze alternations when requesting food from a human who was either visually attentive or visually inattentive. Similarly to human infants, both bonobos and chimpanzees produced gaze alternations, and did so more frequently when a human communicative partner was visually attentive. However, unlike humans, who gaze alternate frequently from early in development, chimpanzees did not begin to gaze alternate frequently until adulthood. Bonobos produced very few gaze alternations, regardless of age. Thus, it may be the early emergence of gaze alternations, as opposed gaze alternations themselves, that is derived in the human lineage. The distinctively early emergence of gaze alternations in humans may be a critical underpinning for the development of complex human social‐cognitive abilities.     

Perceptions of Credibility for a Memory Report of a Single Versus Repeated Event

Summary: When a person experiences an event that has multiple similar instances (i.e., a repeated event), memories for details that change across instances are challenging to recall. We expected that third parties would perceive memory reports of instances of repeated events as less credible than they would unique (i.e., single) events. Undergraduates participated in a single or repeated event, during which critical details were presented. Participants were asked to recall the session 2 days later, and memory reports were video recorded. New participants then viewed one video and evaluated the credibility of the speaker's memory report. Overall, repeated‐event reports were seen as less credible than were single‐event reports, despite the reports being equally accurate. Although credibility research in the context of repeated events has focused exclusively on child populations, a range of applications exists for adults (e.g., criminal and industrial eyewitnesses, and asylum seekers); we discussed our findings in these areas.Copyright © 2017 John Wiley & Sons, Ltd.