Measurement of the Q

We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9 GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02 GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.

Probing quark-gluon interactions with transverse polarized scattering.

We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.

Behavior problems of children with Down syndrome and life events.

Behavior problems of 44 children with Down syndrome between the ages of 6 and 15 and 44 controls without mental retardation matched for age, sex, and socioeconomic status were compared on the basis of mother and teacher ratings. Ratings from both sources indicated that children with Down syndrome had more behavior problems, in particular attention deficit, noncompliance, thought disorder, and social withdrawal. Life events from the past year were significantly associated with mother but not teacher ratings of Down syndrome behavior problems.

Simulation and counterconditioning as adjuncts to pharmacotherapy for invasive pediatric procedures.

Behavioral counterconditioning was conducted during simulated medical routines to supplement medical management of five children's distress during invasive procedures (bone marrow aspiration, lumbar puncture, tracheostomy care, venipuncture, and finger pricks). Preferred activities were paired in vivo with medical stimuli, and differential positive reinforcement was provided contingent on engagement with the preferred activities and on compliance with adult instructions, first during simulations and later during actual procedures. Data on cooperation, escape/avoidance, and negative vocalizations were evaluated using both single-subject experimental methods and a baseline-treatment group statistical comparison. Results support the benefits of this approach as an adjunctive intervention to decrease behavioral distress in some children requiring repeated invasive procedures. Discussion emphasizes the potential for training medical personnel to implement these techniques preventively, for decreasing or discontinuing sedation for some children treated under local anesthesia, and for preparing children with developmental disabilities for invasive procedures.

Reduction of eye gouging using a response interruption procedure.

A profoundly retarded male with severe congenital impairment of vision and hearing was treated for self-inflicted eye gouging. Prior to intervention, continuous mechanical restraint was required to prevent the response, precluding participation in educational and play activities. The response topography, the nature of the client's deficits, and a preliminary behavioral and medical assessment suggested that the response functioned as a source of sensory self-stimulation. Presentation of toys plus differential reinforcement of other behavior (DRO) as alternate sources of stimulation during baseline had no impact on eye gouging. The introduction of a contingent response interruption procedure reduced eye gouging and decreased the amount of time spent in restraints. Treatment effects were replicated in a group setting, and in the natural environment. Parents and school personnel were trained to use the treatment, and eye gouging remained infrequent at a 9-month follow-up.

Assessment and treatment of multiple behavior problems exhibited by a profoundly retarded adolescent.

The severe aggression and noncompliance of a profoundly retarded blind male were subjected to extensive behavioral assessment in order to identify controlling variables. The assessment, conducted across settings and therapists, suggested that these inappropriate behaviors functioned to avoid or terminate nonpreferred activities. Intervention consisted of manual guidance when there was noncompliance with instructions and edible reinforcement upon compliance; there were no direct contingencies for the inappropriate behaviors. Treatment procedures were implemented in a multiple baseline design across therapists and settings. Results show that the intervention consistently increased compliance, with concurrent decreases in inappropriate behaviors. Edible reinforcement and neuroleptic medication were withdrawn systematically with no loss of therapeutic gains. Family members and school personnel were trained to use the intervention procedures. Results are discussed in terms of functional assessment, response covariation, compliance training, parent and staff training, and behavioral assessment of the effects of neuroleptic medication.

Behavior analysis, program development, and transfer of control in the treatment of self-injury.

This case study illustrates an empirical approach to the diagnosis, treatment, and controlled follow-up of self-injurious clients. Following an assessment period, during which environmental factors associated with a severely retarded adolescent's self-injury were identified, the contingent application of protective equipment was combined with a differential reinforcement procedure (DRO) and implemented in a multiple baseline design across two hospital settings. Results showed a marked decrease in the rate of self-injury. Upon discharge from the hospital, the program was successfully replicated at the adolescent's residential center, again using a multiple baseline design across settings.

Toward a functional analysis of self-injury.

This study describes the use of an operant methodology to assess functional relationships between self-injury and specific environmental events. The self-injurious behaviors of nine developmentally disabled subjects were observed during periods of brief, repeated exposure to a series of analogue conditions. Each condition differed along one or more of the following dimensions: (1) play materials (present vs absent), (2) experimenter demands (high vs low), and (3) social attention (absent vs noncontingent vs contingent). Results showed a great deal of both between and within-subject variability. However, in six of the nine subjects, higher levels of self-injury were consistently associated with a specific stimulus condition, suggesting that within-subject variability was a function of distinct features of the social and/or physical environment. These data are discussed in light of previously suggested hypotheses for the motivation of self-injury, with particular emphasis on their implications for the selection of suitable treatments.

Behavior analysis of motion control for pediatric neuroimaging.

Magnetic resonance imaging is a promising technological advance used for research and diagnosis of disease. The procedure has no risks, except when uncooperative patients require sedation. Four normal children participated in simulated scans to study the effects of (a) antecedent changes in the imaging environment and (b) operant conditioning of movement inhibition. Changing the environment can decrease movement, but operant contingencies were necessary to decrease movement to a level that, in most cases, would allow the procedure to occur without sedation.

A preliminary neuroimaging study of preschool children with ADHD.

Attention-deficit/hyperactivity disorder (ADHD) is a developmental disorder that, by current definition, has onset prior to age 7 years. MRI studies have provided some insight into brain differences associated with ADHD, but thus far have almost exclusively focused on children ages 7 years and older. To better understand the neurobiological development of ADHD, cortical and subcortical brain development should be systematically examined in younger children presenting with symptoms of the disorder. High-resolution anatomical (MPRAGE) images, acquired on a 3.0T scanner, were analyzed in a total of 26 preschoolers, ages 4-5 years (13 with ADHD, 13 controls, matched on age and sex). The ADHD sample was diagnosed using DSM-IV criteria, and screened for language disorders. Cortical regions were delineated and measured using automated methods in Freesurfer; basal ganglia structures were manually delineated. Children with ADHD showed significantly reduced caudate volumes bilaterally; in contrast there were no significant group differences in cortical volume or thickness in this age range. After controlling for age and total cerebral volume, left caudate volume was a significant predictor of hyperactive/impulsive, but not inattentive symptom severity. Anomalous basal ganglia, particularly caudate, development appears to play an important role among children presenting with early onset symptoms of ADHD.

3He spin-dependent cross sections and sum rules.

We present a measurement of the spin-dependent cross sections for the 3He over -->(e over -->,e')X reaction in the quasielastic and resonance regions at a four-momentum transfer 0.1< or =Q2< or =0.9 GeV2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt-Cottingham and extended Gerasimov-Drell-Hearn sum rules for the first time. The data are also compared to an impulse approximation calculation and an exact three-body Faddeev calculation in the quasielastic region.

Proton spin structure in the resonance region.

We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeV

Recoil-proton polarization in high-energy deuteron photodisintegration with circularly polarized photons.

We measured the angular dependence of the three recoil-proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.

Precision Rosenbluth measurement of the proton elastic form factors.

We report the results of a new Rosenbluth measurement of the proton electromagnetic form factors at Q2 values of 2.64, 3.20, and 4.10 GeV2. Cross sections were determined by detecting the recoiling proton, in contrast to previous measurements which detected the scattered electron. Cross sections were determined to 3%, with relative uncertainties below 1%. The ratio mu(p)G(E)/G(M) was determined to 4%-8% and showed mu(p)G(E)/G(M) approximately 1. These results are consistent with, and much more precise than, previous Rosenbluth extractions. They are inconsistent with recent polarization transfer measurements of similar precision, implying a systematic difference between the techniques.

A video system to help children cooperate with motion control for radiation treatment without sedation.

A behavioral program for teaching children to cooperate with radiation treatment without sedation was previously published in this journal. Outcome data from using that program with 11 more children are reported here. For these children, an apparatus was developed to display video cartoons and movies during their behavioral training, radiation therapy planning, and daily treatments. Literature supporting the use of video displays to provide relaxation, distraction, and counterconditioning during medical procedures is highlighted. With behavioral training and the video display, 9 of the 11 children were able to avoid any sedation for daily treatments. A 10th child was able to avoid general anesthesia for his last 10 daily treatments. The advantages and limitations of behavioral training as an alternative to repeated sedation or anesthesia for radiation treatment are discussed.

Behavioral training of motion control in young children undergoing radiation treatment without sedation.

Preschool-age children undergoing radiation treatment for malignancies often require daily sedation or general anesthesia to assure adequate motion control. A few older children with severe anxiety reactions, a history of behavior problems, or developmental handicaps have similar problems with radiotherapy. The use of sedation or anesthesia adds risk and expense to a procedure that does not require their administration for pain management. This report describes an alternative approach using behavior analysis to teach cooperation and motion control to preschoolers and older children with special needs. Outcome data are presented for 10 children between the ages of 3 and 7. Eight of the 10 appeared to benefit from the behavioral program. These eight cooperated with radiation treatments without the need for repeated sedation or anesthesia. The benefits and limitations of this approach are discussed along with the need for additional research.

Behavior management of aggressive sequela after Reye's syndrome.

This study describes the use of behavior management procedures to reduce the occurrence of severe behavioral sequela in a 14-year-old, post-Reye's syndrome male. Prior to intervention the client exhibited severe self-injurious, hyperaggressive, and food refusal behaviors that precluded any opportunities for rehabilitation, placed him at severe medical risk, and made him a candidate for institutional placement. With contingent restraint, in vivo desensitization, and reinforcement contingencies it was possible to control these behaviors and begin intensive rehabilitation. Subsequently, the client returned to his family and community day school for the severely handicapped where he remains five years later.

Behavioural training during acute brain trauma rehabilitation: an empirical case study.

Operant conditioning-based behavioural interventions are commonly used for the behavioural problems of individuals with mental retardation. There is also growing evidence of the benefits of these interventions for treating some of the behavioural problems of individuals with acquired cognitive deficits resulting from brain trauma. However, the effects of behavioural interventions on behavioural problems occurring during acute neurorehabilitation, when orientation and memory are most impaired, have not been studied. In this empirical case study, operant conditioning-based procedures were applied with an 8-year-old girl recovering from brain trauma and related neurosurgery. Screaming, non-compliance and aggression, which were disrupting rehabilitation therapies and follow-up neuroimaging, were treated using differential positive reinforcement techniques. Beneficial behavioural intervention effects were demonstrated using single-subject experimental methods. Aberrant behaviour during physical and occupational therapies was reduced, and cooperation with a computerized tomography (CT) scan without sedation was accomplished using operant behavioural intervention. Results support the use of operant interventions early in recovery from brain trauma, and highlight the importance of interdisciplinary collaboration for the implementation and further study of early behavioural interventions.

Reliability and validity of the brief behavioral distress scale: a measure of children's distress during invasive medical procedures.

OBJECTIVE: To evaluate the reliability and validity of a new observational measure of children's procedure-related distress behaviors, the Brief Behavioral Distress Scale (BBDS), to provide clinicians with an efficient, economical alternative measure that does not depend on continuous interval coding. METHODS: Forty-eight randomly selected videotaped invasive medical procedures performed on children (ages 2 to 10 years) with chronic illness were coded with the BBDS and the Observation Scale of Behavioral Distress (OSBD). Reliability and validity analyses along with item analysis were conducted. RESULTS: Total distress scores of the BBDS were highly correlated with six of seven concurrent validity measures from multiple sources (i.e., OSBD, parent ratings, two nurse ratings, child self-report, and a physiological arousal measure, heart rate) (range r =.57-.76, p <.001-.0001). A robust association was found between the BBDS distress scores and OSBD total distress scores (r =.72, p <.0001). For two concurrent validity measures, the BBDS demonstrated stronger associations than did the OSBD. Interrater reliability was high for each BBDS distress behavior category. CONCLUSIONS: Based on the findings reported, the BBDS is a reliable and valid measure of children's procedure-related distress with functional utility in both research and clinical settings.