Acquisition and retention of gestures by apraxic patients

The purpose of this study was to examine whether apraxic-aphasic patients with parietal lesions had difficulty learning lists of gestures and whether the performance deficits they displayed resulted from an inability either to consolidate this information in memory or to retrieve the information once stored. The findings indicate that apraxic-aphasic patients do have difficulty acquiring lists of gestures. This inability to reproduce gestural information was not associated with a retrieval disorder, but instead the apraxic-aphasic subjects could not consolidate the information in memory.     

An auto-adjusting shaping procedure

A variable interval (VI) schedule is described that automatically adjusts the programmed rates of reinforcement in accordance with the rates of responding of subjects during the two immediately preceding 30-sec time intervals. The schedule prescribes that as rate of responding decreases, programmed reinforcement rate increases, and that when rate of responding increases, reinforcement rate decreases. Thus, programmed reinforcement rate is adjusted continuously until some target value is reached. Ten rats were exposed to this procedure five times a day at 1-h intervals. The target, set at VI 120 sec, was reached by most subjects within 4 days of training. Subsequently, all subjects responded consistently during five daily 1-h sessions with VI 120 sec. This procedure speeds up the training of subjects on long VI schedules and substantially reduces the time and effort spent observing the subjects and adjusting the schedule parameter value during the early development of responding.     

Optimizing Engagement in Behavioral Parent Training: Progress Toward a Technology-Enhanced Treatment Model

Low-income families are more likely to have a child with an early-onset Behavior Disorder (BD); yet, socioeconomic strain challenges engagement in Behavioral Parent Training (BPT). This study follows a promising pilot to further examine the potential to cost-effectively improve low-income families’ engagement in and the efficiency of BPT. Low-income families were randomized to (a) Helping the Noncompliant Child (HNC; McMahon & Forehand, 2003), a weekly, mastery-based BPT program that includes both the parent and child or (b) Technology-Enhanced HNC (TE-HNC), which includes all of the standard HNC components plus a parent mobile application and therapist web portal that provide between-session monitoring, modeling, and coaching of parent skill use with the goal of improved engagement in the context of financial strain. Relative to HNC, TE-HNC families had greater homework compliance and mid-week call participation. TE-HNC completers also required fewer weeks to achieve skill mastery and, in turn, to complete treatment than those in HNC without compromising parent satisfaction with treatment; yet, session attendance and completion were not different between groups. Future directions and clinical implications are discussed.     

Empirical Evidence for Extended Cognitive Systems

We present an empirically supported theoretical and methodological framework for quantifying the system-level properties of person-plus-tool interactions in order to answer the question: “Are person-plus-tool-systems extended cognitive systems?” Nineteen participants provided perceptual judgments regarding their ability to pass through apertures of various widths while using visual information, blindfolded wielding a rod, or blindfolded wielding an Enactive Torch—a vibrotactile sensory-substitution device for detecting distance. Monofractal, multifractal, and recurrence quantification analyses were conducted to assess features of person-plus-tool movement dynamics. Trials where people utilized the rod or Enactive Torch demonstrated stable “self-similarity,” or indices of healthy and adaptive single systems, regardless of aperture width, trial order, features of the participants’ judgments, and participant characteristics. Enactive Torch trials exhibited a somewhat greater range of dynamic fluctuations than the rod trials, as well as less movement recurrence, suggesting that the Enactive Torch allowed for more exploratory movements. Findings provide support for the notion that person-plus-tool systems can be classified as extended cognitive systems and a framework for quantifying system-level properties of these systems. Implications concerning future research on extended cognition are discussed.     

Infants of “depressed” mothers interact better with their nondepressed fathers

To determine whether infants of “depressed” mothers interact better with their nondepressed fathers, twenty-six 3- to 6-month-old infants were videotaped during face-to-face interactions with their parents. The “depressed” mother group consisted of twelve 3- to 6-month-old infants and their “depressed” mothers and nondepressed fathers. The control group was composed of 14 nondepressed mothers and nondepressed fathers and their 3- to 6-month-old infants. In the “depressed” mother group, the nondepressed fathers received better interaction ratings than the “depressed” mothers. In turn, the infants received better interaction ratings when they interacted with their nondepressed fathers than with their “depressed” mothers. In contrast, nondepressed fathers and mothers and their infants in the control group did not differ on any of their interaction ratings. These findings suggest that infants' difficult interaction behaviors noted during interactions with their “depressed” mothers may not extend to their nondepressed fathers. The data are discussed with respect to the notion that nondepressed fathers may “buffer” the effects of maternal depression on infant interaction behavior.     

Effects of neonatal treatment with 1-(2,5-dimethoxy-4-lodophenyl)-2 aminopropane HCI (DOI) and ritanserin on agonistic behavior in adult male and female rats

The role played by the neonatal 5-hydroxytryptamine (5HT) system in the organization and sexual differentiation of adult agonistic behavior was investigated in rats. Focus was on the 5HT2 receptor subtype, which has been demonstrated to be involved in agonism control in the adult. 5HT2 activity was experimentally manipulated by administration of a specific agonist [1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane HCl (DOI)] or antagonist (ritanserin) during the second week of life, when serotonin is known to concur to anatomical and behavioral sexual differentiation. Interactions between early 5HT2 activity, genetic sex, and neonatal circulating testosterone (T) were studied by administering the ligands to males, females, and androgenized females. At adulthood, the animals were tested for both aspects of agonism, i. e., aggression and defense, in a 20-min confrontation with an unfamiliar conspecific of the same sex, age, body weight, and social experience. Neonatal administration of the 5HT2 antagonist ritanserin increased aggression independently of sex; it also increased defense, but this effect was confined to males. The agonist DOI had no effect on aggression, but enhanced defense in males and androgenized females, with an effect which depended therefore more on neonatal T than genetic sex. Females appeared in general less sensitive to neonatal 5HT2 manipulation than both androgenized females and males; this suggests that neonatal T is crucial for experimental modifications of neonatal 5HT2 activity to have any consistent effect on adult agonistic behavior. On the other hand, effects observed in males and androgenized females were dependent on the behavior considered and the drug administered. This was especially evident for defense, enhanced by ritanserin in males only, and in both males and androgenized females by DOI. Neonatal 5HT2 activity seems therefore to play a role in the modulation of adult agonistic behaviors, which depends on the behavior considered and is under multiple control of genetic sex and hormonal neonatal substrate. © 1994 Wiley-Liss, Inc.     

The link between maternal and child verbal abilities: An indirect effect through maternal responsiveness

Language abilities in early childhood show stability over time and play an important role in the development of other cognitive processes. Identifying modifiable environmental risk factors is important to informing prevention and early intervention efforts. Maternal verbal ability has been previously linked to child verbal ability. The current study examined whether maternal and child verbal abilities were linked indirectly through early childhood maternal responsiveness. Data come from a longitudinal birth cohort study. Participants included 133 mothers and their children recruited from maternity wards shortly after birth. Maternal verbal ability was measured using the Vocabulary subtest from the Wechsler Abbreviated Scale of Intelligence, Second Edition (child age 8 months). Child verbal ability was assessed using the Peabody Picture Vocabulary Test (36 months). A latent maternal responsiveness variable was estimated using three developmentally sensitive indicators; one during infancy (child age 8 months) and two when children were 36 months. Results of a structural equation model indicated a significant indirect effect from maternal verbal abilities to child verbal abilities through maternal responsiveness. This indirect path was significant even after inclusion of another indirect path from maternal executive functioning to child verbal ability through maternal responsiveness (which was not significant). Future studies will benefit from experimental, genetically sensitive and/or cross‐lagged designs to allow for conclusions related to directionality and causality. This body of research has implications for the study of the intergenerational transmission of verbal abilities and associated skills, behaviours and adaptive outcomes.     

Modeling the personality of dyads and groups

The paper presents a methodological approach for assessing the personality of a dyad or a group, a concept that is not equivalent to the sum, or mean, of the individual scores. We illustrate how the logic of the multitrait multimethod approach, which is a familiar technique for establishing construct validity, can be extended to assess the construct of a relationship "personality." The model, which we call the latent group model, provides a decomposition and comparison of individual-level and group-level variance in a given trait, and the individual-level and group-level covariance or correlation between two traits. The model is also extended to the assessment of stability of the individual and group level traits. Throughout the paper, we draw connections between related methods and show how the latent group model can be estimated through hierarchical linear modeling.     

A case study of mediated learning, delayed auditory feedback, and motor repatterning to reduce stuttering

A case study of DW, an 11-yr. old monolingual, English-speaking boy who exhibits stuttering, language delay, and ADHD is presented. DW experienced only limited improvement during stuttering therapy received in public schools, according to parents and the public school clinician. The purpose of this case study was to assess whether fluency treatment which incorporated Mediated Learning, Delayed Auditory Feedback, and Speech Motor Repatterning would enhance progress. Therapy was delivered in two treatments, with each treatment being 5 wk. of intense therapy, separated by one year. Treatment 1 of combined Mediated Learning and Delayed Auditory Feedback yielded improvement in fluency, judged by parents and the teacher to be clinically significant. The improved fluency was maintained for one year when DW was pretested for participation in Treatment 2, which combined Mediated Learning, Delayed Auditory Feedback, and Speech Motor Repatterning Exercises. As no conclusions are possible, further study is needed.