Spatial selectivity in visual search

To what extent does successful search for a target letter in a visual display depend on the allocation of attention to the target’s spatial position? To investigate this question, we required subjects to discriminate the orientation of a briefly flashed U-shaped form while searching for a target letter. Performance operating characteristics (POCs) were derived by varying the relative amounts of attention subjects were to devote to each task. Extensive tradeoffs in performance were observed when the orientation form and target letter occurred in nonadjacent display positions. In contrast, the tradeoff was much more restricted when the two targets occurred in adjacent positions. These results suggest that the interference between simultaneous visual discriminations depends critically on their separation in visual space. Both visual search and form discrimination require a common limited-capacity visual resource.     

Haptic cues for orientation and postural control

Haptic cues from fingertip contact with a stable surface attenuate body sway in subjects even when the contact forces are too small to provide physical support of the body. We investigated how haptic cues derived from contact of a cane with a stationary surface at low force levels aids postural control in sighted and congenitally blind individuals. Five sighted (eyes closed) and five congenitally blind subjects maintained a tandem Romberg stance in five conditions: (1) no cane; (2, 3) touch contact (<2 N of applied force) while holding the cane in a vertical or slanted orientation; and (4, 5) force contact (as much force as desired) in the vertical and slanted orientations. Touch contact of a cane at force levels below those necessary to provide significant physical stabilization was as effective as force contact in reducing postural sway in all subjects, compared to the no-cane condition. A slanted cane was far more effective in reducing postural sway than was a perpendicular cane. Cane use also decreased head displacement of sighted subjects far more than that of blind subjects. These results suggest that head movement control is linked to postural control through gaze stabilization reflexes in sighted subjects; such reflexes are absent in congenitally blind individuals and may account for their higher levels of head displacement.     

Group CBT for Externalizing Disorders in Urban Schools: Effect of Training Strategy on Treatment Fidelity and Child Outcomes

Public schools are an ideal setting for the delivery of mental health services to children. Unfortunately, services provided in schools, and more so in urban schools, have been found to lead to little or no significant clinical improvements. Studies with urban school children seldom report on the effects of clinician training on treatment fidelity and child outcomes. This study examines the differential effects of two levels of school-based counselor training: training workshop with basic consultation (C) vs. training workshop plus enhanced consultation (C +) on treatment fidelity and child outcomes. Fourteen school staff members (counselors) were randomly assigned to C or C +. Counselors implemented a group cognitive behavioral therapy protocol (Coping Power Program, CPP) for children with or at risk for externalizing behavior disorders. Independent coders coded each CPP session for content and process fidelity. Changes in outcomes from pre to post were assessed via a parent psychiatric interview and interviewer-rated severity of illness and global impairment. Counselors in C + delivered CPP with significantly higher levels of content and process fidelity compared to counselors in C. Both C and C + resulted in significant improvement in interviewer-rated impairment; the conditions did not differ from each other with regard to impairment. Groups did not differ with regard to pre- to- posttreatment changes in diagnostic severity level. School-based behavioral health staff in urban schools are able to implement interventions with fidelity and clinical effectiveness when provided with ongoing consultation. Enhanced consultation resulted in higher fidelity. Enhanced consultation did not result in better student outcomes compared to basic consultation. Implications for resource allocation decisions with staff training in EBP are discussed.     

Establishing initial auditory‐visual conditional discriminations and emergence of initial tacts in young children with autism spectrum disorder

Children with autism spectrum disorder (ASD) often display impaired listener skills, and few studies have evaluated procedures for establishing initial auditory‐visual conditional discrimination skills. We developed and evaluated a treatment package for training initial auditory‐visual conditional discriminations based on the extant research on training such discriminations in children with ASD with at least some preexisting skills in this area. The treatment package included (a) conditional‐only training, (b) prompting the participant to echo the sample stimulus as a differential observing response, (c) prompting correct selection responses using an identity‐match prompt, (d) using progressively delayed prompts, and (e) repeating trials until the participant emitted an independent correct response. Results indicated all participants mastered all listener targets, and the two participants for whom we tested the emergence of corresponding tacts showed mastery of most tacts without direct training. We discuss these results relative to prior research on listener skills and tacts.