GABAergic and glycinergic inhibition modulate monaural auditory response properties in the avian superior olivary nucleus.

The superior olivary nucleus (SON) is the primary source of inhibition in the avian auditory brainstem. While much is known about the role of inhibition at the SON's target nuclei, little is known about how the SON itself processes auditory information or how inhibition modulates these properties. Additionally, the synaptic physiology of inhibitory inputs within the SON has not been described. We investigated these questions using in vivo and in vitro electrophysiological techniques in combination with immunohistochemistry in the chicken, an organism for which the auditory brainstem has otherwise been well characterized. We provide a thorough characterization of monaural response properties in the SON and the influence of inhibitory input in shaping these features. We found that the SON contains a heterogeneous mixture of response patterns to acoustic stimulation and that in most neurons these responses are modulated by both GABAergic and glycinergic inhibitory inputs. Interestingly, many SON neurons tuned to low frequencies have robust phase-locking capability and the precision of this phase locking is enhanced by inhibitory inputs. On the synaptic level, we found that evoked and spontaneous inhibitory postsynaptic currents (IPSCs) within the SON are also mediated by both GABAergic and glycinergic inhibition in all neurons tested. Analysis of spontaneous IPSCs suggests that most SON cells receive a mixture of both purely GABAergic terminals, as well as terminals from which GABA and glycine are coreleased. Evidence for glycinergic signaling within the SON is a novel result that has important implications for understanding inhibitory function in the auditory brainstem.

Rab3a deletion reduces vesicle docking and transmitter release at the mouse diaphragm synapse.

Rab3a is a small GTP binding protein associated with presynaptic vesicles that is thought to regulate vesicle targeting to active zones. Although this rab3a function implies that vesicle docking and action potential-evoked release might be inhibited in rab3a gene-deleted synapses, such inhibition has never been demonstrated. To investigate vesicle docking at the neuromuscular junction of rab3a gene-deleted (rab3a(-)) mice, we performed electron microscopy analysis of the diaphragm slow-fatigue (type I) synapses. We found a significant (26%) reduction in the number of vesicles docked to the presynaptic membrane in rab3a(-) terminals, although intraterminal vesicles were not affected. Aiming to detect possible changes in quantal release due to rab3a gene deletion, we minimized the variability between preparations employing focal recordings of synaptic responses from visualized type I endplates. We found a significant decrease in both evoked (27% reduction in quantal content) and spontaneous (28% reduction in mini frequency) quantal release. The decrease in the evoked release produced by rab3a deletion was most pronounced at reduced extracellular Ca(2+) concentrations (over 50% decrease at 0.5 and 0.2 mM Ca(2+)). By manipulating extracellular calcium, we demonstrated that calcium cooperativity is not altered in rab3a(-) synapses, however calcium sensitivity of quantal release is affected. Thus, we demonstrated that rab3a positively regulates docking and basal quantal release at the mouse neuromuscular junction. This result is consistent with the proposed role of rab3a in trafficking and targeting vesicles to the active zones.

The prenatal visit.

In their role as advocates for children and families, pediatricians are in an excellent position to support and guide parents during the prenatal period. Prenatal visits allow the pediatrician to gather basic information from parents, provide information and advice to them, and identify high-risk situations in which parents may need to be referred to appropriate resources for help. In addition, prenatal visits are the first step in establishing a relationship between the pediatrician and parents and help parents develop parenting skills. The prenatal visit may take several possible forms depending on the experience and preferences of the parents, competence and availability of the pediatrician, and provisions of the health care plan.

Binaural function in children with attention-deficit hyperactivity disorder.

OBJECTIVE: To evaluate the basic binaural function of children with attention-deficit hyperactivity disorder (ADHD). DESIGN: Case-control study. Measures of binaural function were compared for children with and without ADHD. SUBJECTS: Forty-two children; 26 had ADHD and 16 were normal controls. INTERVENTIONS: None. RESULTS: For detection tasks, no differences were seen between children with ADHD and controls. For speech recognition tasks, the younger children with ADHD did not perform as well as the controls. CONCLUSIONS: Younger children with ADHD might have a reduced processing efficiency for signal recognition in certain types of noise, but not for signal detection.

Family-focused behavioral pediatrics: clinical techniques for primary care.

Whenever a behavioral or psychosocial problem presents in a child, all members of the family are affected. Conversely, when the problem lies within the family, the child is affected and often presents as the symptomatic patient. The goals of family-focused pediatrics are to: 1) determine the need for a family intervention; 2) conduct a family interview-assessment; 3) clarify the issues; 4) teach healthy communication skills and interactions; and 5) facilitate generation of family goals and solutions. Family-focused strategies provide an effective, brief, and timely approach that can aid the pediatrician in helping children and their families function in more healthy and satisfying ways.

The first interview with a family.

The family interview is the essence of family-focused pediatric care. The first interview is especially critical because it provides the creation of a therapeutic alliance, an assessment of the family and its concerns, and the formation of goals and solutions. Knowing interviewing techniques will ensure a successful outcome for the family and the pediatrician.

Brief solution-focused strategies for behavioral pediatrics.

In an era of shrinking resources and managed care, brief models of psychotherapy are receiving increasing attention. One of the newest and innovative of those, brief, solution-focused therapy, is particularly efficient, because it concentrates on the present and the future; builds on strengths; focuses on clear, realistic goals; uses tasks; and develops client cooperation and efficacy. Parents have long turned to pediatricians for help in addressing a variety of child-rearing and other family concerns. Behavioral pediatricians who are looking for time-effective ways to counsel families should consider the six solution-focused techniques described in this article and pursue training in this approach to family therapy, yet another example of family-focused pediatrics.

Talkative children: verbal fluency as a marker for problematic peer relationships in clinic-referred children with attention deficits.

The relationships between attention deficits, hyperactivity, neurodevelopmental performance, and problematic peer relationships were examined in 99 consecutive children (ages 9 to 11 years) referred for school problems to a clinic. Using a teachers' rating scale, 32 children with cognitive inattention and a comparison group of 67 children without cognitive inattention were identified. The former group comprised children who met criteria for Attention Deficit-Hyperactivity Disorder (ADHD). The latter group comprised children with learning disorders and school problems, 42 of whom did not meet criteria for ADHD. Analysis indicated that the study group had greater peer problems, as estimated by teachers' ratings, than the comparison group. Cognitive inattention was related to peer problems over and above the effects of hyperactivity. Neurodevelopmental predictors of peer problems were different among children with ADHD and those without ADHD. Among children with ADHD, proficiency in tasks of verbal fluency was significantly predictive of peer problems. These preliminary findings suggest that children showing teacher-rated cognitive inattention also manifest significant peer problems and that the presence of strong verbal fluency may make these children prone to inappropriate excessive talking and, subsequently, to alienation of peers.

Interpersonal disabilities: social skill deficits in older children and adolescents. Their description, assessment, and management.

Good social skills are critical for peer acceptance and friendship formation, which are developmental missions for the older child and adolescent. Good social skills can be developed and can favorably influence other domains of function. A sensitive and comprehensive assessment and management plan is essential. Pediatricians have a unique vantage point because of their familiarity with a child, the family, the school and community, and their knowledge of child development and behavior. Pediatricians can therefore play a central role in the assessment, management, and follow-up of social skills problems.

Neurodevelopmental study of writing disorders in middle childhood.

This study investigated patterns of neurodevelopmental dysfunction in children with writing disorders (WD). Records of children, ages 9 to 15 years, referred to a school problems clinic were examined. Using teacher questionnaire information, including ratings of writing legibility, mechanics, rate, linguistic sophistication, and spelling, 99 cases of WD were found. Sixty-three children without WD served as clinic controls. A cluster analysis revealed four discrete subtypes of WD and two non-WD control clusters. The four WD clusters were found to have different patterns of writing and reading characteristics. Neurodevelopmental tests discriminated among the clusters (F = 2.8, p less than .0001), and an examination of neurodevelopmental performance characteristics among the clusters showed different patterns of strengths and weaknesses. An empirically derived subtyping of WD is proposed: WD with fine motor and linguistic deficits, WD with visual-spatial deficits, WD with attention and memory deficits, and WD with sequencing deficits. This subtyping, if confirmed in a population study, may have important diagnostic and therapeutic implications.

Neurodevelopmental readiness for adolescence: studies of an assessment instrument for 9- to 14-year-old children.

The Pediatric Examination of Educational Readiness at Middle Childhood (PEERAMID) is a neurodevelopmental examination for 9- to 14-year-old children. The examination was designed largely for use by developmental-behavioral pediatricians as a way of assessing certain critical developmental functions, including attention, memory, language, and motor coordination in children with school problems. Preliminary field testing of the PEERAMID was carried out in one community, and subsequently a revised version was standardized on randomly selected subjects from three communities near Boston, Massachusetts, and on groups of children from those towns said to be having significant problems at school. Additionally, the examination was used for the evaluation of 106 consecutive patients referred to the School Function Program at The Children's Hospital in Boston. Statistically significant performance differences discriminated between children with normal academic performance and those with school problems in the community as well as in the referral setting. It was discovered that children with school problems tended to have clusters of dysfunction, whereas normally achieving youngsters more often harbored no developmental dysfunctions or perhaps one or two areas of difficulty. It is believed that the PEERAMID can be a useful instrument in serving as part of a pediatric contribution to a multidisciplinary assessment in children in this age group.

Recurrent chest pain in children.

Chest pain in children is relatively common and is often benign and self-limited, but it has received scant attention in the pediatric literature. The author offers rational guidelines for diagnosing the causes of chest pain and comments on the management and follow-up of the patient.