Manipulating establishing operations to verify and establish stimulus control during mand training

Acquisition of verbal behavior is a major goal of interventions for children with developmental disabilities. We evaluated the effectiveness of manipulation of an establishing operation for functional discriminated mands. Four individuals with developmental disabilities participated in a training procedure designed to teach two separate mands for two separate preferred items. Participants were taught to mand using picture cards. Following training, the manipulation of the establishing operation was used to assess and establish discriminated manding. This manipulation involved providing free access to one of the preferred items, such that there should be no motivation to ask for it, while motivation to ask for the other item remained in place. Three of the 4 participants acquired discriminated manding using topographically similar responses (picture cards). One participant did not acquire a discriminated mand until topographically distinct mands were taught (vocal and picture card). Results suggest that discrimination training is not necessarily sufficient to teach discriminated manding when more than one picture card showing preferred items is used. In addition, manipulation of the establishing operation served as an appropriate assessment tool for the verification of discriminated manding as well as a possible training tool to establish discriminated manding.     

Coordination of rapid stepping with arm pointing: anticipatory changes and step adaptation

The present study explored whether rapid stepping is influenced by the coordination of an arm pointing task. Nine participants were instructed to (a) point the index finger of the dominant arm towards a target from the standing posture, (b) initiate a rapid forward step with the contralateral leg, and (c) synchronize stepping and pointing (combined task). Force plate and ankle muscle electromyography (EMG) recordings were contrasted between (b) and (c). In the combined task, the arm acceleration trace most often peaked around foot-off, coinciding with a 15% increase in the forward acceleration of the center of gravity (CoG). Backward displacement of the center of foot pressure at foot-off, duration of anticipatory postural adjustments (APAs) and ankle muscle EMG activity remained unchanged. In contrast, durations of swing phase and whole step were reduced and step length was smaller in the combined task. A reduction in the swing phase was correlated with an increased CoG forward acceleration at foot-off. Changes in the biomechanics of step initiation during the combined task might be ascribed to the postural dynamics elicited by arm pointing, and not to a modulation of the step APAs programming.     

The virtual haptic display: A device for exploring 2-D virtual shapes in the tactile modality

In order to understand better the processes involved in the perception of shape through touch, someelement of control is required over the nature of the shape presented to the hand and the presentation timing. To that end, we have developed a cost-effective, computer-controlled apparatus for presenting haptic stimuli using active touch, known as a virtual haptic display (VHD). The operational principle behind this device is that it translates black and white visual images into topographic, 2-D taxel (tactile pixel) arrays, along the same principle using in Braille letters. These taxels are either elevated or depressed at any one time representing white and black pixel colors of the visual image, respectively. To feel the taxels, the participant places their fingers onto a carriage which can be moved over the surface of the device to reveal a virtual shape. We conducted two experiments and the results show that untrained participants are able to recognize different, simple and complex, shapes using this apparatus. The VHD apparatus is therefore ideal at presenting 2-Dshapes through touch alone. Moreover,this device and its supporting software can also be used for presenting computer-controlled stimuli in cross-modal experiments.     

The impact of misleading questions on eyewitness memory in children and adults

The study examined developmental patterns of the negative effect of misleading post‐event information in two different kinds of eyewitness interviews. A total of 284 subjects aged between five and 64 years were shown a short video about a theft and three weeks as well as four weeks later questioned about it. The social pressure in the interview after three weeks was manipulated by asking half of the subjects suggestive and misleading questions. The other half was asked open‐ended and unbiased questions. In the neutral interview four weeks later, all subjects were asked the same set of recognition questions about the event. The results revealed that preschoolers in particular had problems with the interplay between cognitive and social factors (social pressure induced through the wording of the misleading questions) in the interview setting after three weeks. In the neutral recognition test, all age groups were shown to suffer from prior misinformation to about the same extent. However, with an exception in the group of 6‐year‐old children the negative effect of prior misinformation on the accuracy of recognition proved to be due to items that were peripheral to the observed event. Copyright © 2000 John Wiley & Sons, Ltd.     

Relationship‐based intervention with at‐risk mothers: Factors affecting variations in outcome

A previous group comparison had shown that in families experiencing the UCLA Family Development Project intervention as opposed to a group that did not, mothers became more responsive to the needs of their infants, and the infants were more secure in their attachment to their mothers. The present study asks whether variations in these outcomes following participation in a relationally based intervention are anticipated by maternal involvement in the intervention, partner support, personality dimensions, and mother–infant interactions that were assessed early in the intervention process. The sample consists of 46 mothers at risk for inadequate parenting who also were poor and generally lacked support. It was found that variations at 12 months of age in the child's secure response to separation, his or her expectation of being cared for (felt security), and the mother's responsiveness to need are anticipated by variations in the mother's 6‐ to 12‐month involvement in the home‐visiting intervention, the quality of her partner's support as measured at six months, and her own trust, ability to form stable relationships, and lack of self doubt. Parents who, at one month, were responsive to the needs of their more soothable babies were more likely to have secure children at 12 months, but these associations were not as robust as those summarized above. © 2000 Michigan Association for Infant Mental Health.     

Studying the process of psychoanalytic parent–infant psychotherapy: Embodied and discursive aspects

This paper presents findings from an intensive, mixed methods case study of one session of psychoanalytic parent–infant psychotherapy (PPIP) addressing early relational trauma, and aims to shed light on the multimodal interactive processes that take place in the moment-to-moment exchanges comprising the therapeutic encounter. Different research methods were used on video material from PPIP sessions, including microanalysis of adult–infant interactions, discourse analysis of talk, and coding systems developed to study parent–infant interaction. These different perspectives were brought together with the clinical narrative to illuminate the complex, dynamic processes of parent–infant–therapist interaction. More specifically, the detailed analysis of one interactive episode revealed brief behavioral manifestations of fearful and disoriented states of mind, reflecting dysregulated interaction between mother and infant, which also powerfully affected the therapist. The processes through which the therapist gradually resolves this rupture are also described in detail. Through this pilot study, we were able to show that it is possible to systematically study the process of PPIP. The study contributes to the growing psychotherapy research literature that takes into account both the verbal domain and implicit, interactional processes in therapeutic practice, and underscores the therapist's comprehensive engagement in the therapeutic process.     

Predicting change in middle school students’ leisure-time physical activity participation: A prospective test of the trans-contextual model

We applied the trans-contextual model (TCM) to examine the effects of middle school students’ perceived autonomy support from their physical education (PE) teachers on autonomous motivation toward PE in school and, critically, autonomous motivation toward, and actual participation in, leisure-time physical activity (PA). The research adopted a three-wave prospective design enabling the modeling of change in the TCM constructs over time. Middle school students (N = 248) aged from 12 to 16 years reported their perceived autonomy support, autonomous motivation in PE, autonomous motivation toward leisure-time PA, attitudes, subjective norms, perceived behavioral control (PBC), intentions for PA in leisure-time, and leisure-time PA participation. The psychological constructs and leisure-time PA were measured at baseline (T0) and at a first follow-up occasion (T1) 5 weeks later. Another measure of PA was taken at a second follow-up occasion (T2) a further 5 weeks later. A single-indicator structural equation model using residualized change scores revealed that perceived autonomy support predicted autonomous motivation in PE (β = .345), and autonomous motivation in PE predicted autonomous motivation for leisure-time PA (β = .484). Autonomous motivation toward leisure-time PA predicted attitudes (β = .425), subjective norms (β = .264), and PBC (β = .517). Autonomous motivation toward leisure-time PA (β = .376), attitude (β = .231), and subjective norms (β = .185) predicted intentions toward leisure-time PA, and intentions predicted PA (β = .198). Findings extend research on the TCM by demonstrating its efficacy in predicting change in middle school students’ autonomous motivation across PE and leisure-time contexts, and accounting for change in intentions toward, and actual participation in, leisure-time PA.     

Counting to Infinity: Does Learning the Syntax of the Count List Predict Knowledge That Numbers Are Infinite?

By around the age of 5½, many children in the United States judge that numbers never end, and that it is always possible to add 1 to a set. These same children also generally perform well when asked to label the quantity of a set after one object is added (e.g., judging that a set labeled “five” should now be “six”). These findings suggest that children have implicit knowledge of the “successor function”: Every natural number, n, has a successor, n + 1. Here, we explored how children discover this recursive function, and whether it might be related to discovering productive morphological rules that govern language-specific counting routines (e.g., the rules in English that represent base-10 structure). We tested 4- and 5-year-old children’s knowledge of counting with three tasks, which we then related to (a) children’s belief that 1 can always be added to any number (the successor function) and (b) their belief that numbers never end (infinity). Children who exhibited knowledge of a productive counting rule were significantly more likely to believe that numbers are infinite (i.e., there is no largest number), though such counting knowledge was not directly linked to knowledge of the successor function, per se. Also, our findings suggest that children as young as 4 years of age are able to implement rules defined over their verbal count list to generate number words beyond their spontaneous counting range, an insight which may support reasoning over their acquired verbal count sequence to infer that numbers never end.