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There exists a divide between findings from integrative neuroscience and clinical research focused on mechanisms of psychopathology. Specifically, a clear correspondence does not emerge between clusters of complex clinical symptoms and dysregulated neurobiological systems, with many apparent redundancies. For instance, many mental disorders involve multiple disruptions in putative mechanistic factors (e.g., excessive fear, deficient impulse control), and different disrupted mechanisms appear to play major roles in many disorders. The Research Domain Criteria (RDoC) framework is a heuristic to facilitate the incorporation of behavioral neuroscience in the study of psychopathology. Such integration might be achieved by shifting the central research focus of the field away from clinical description to more squarely examine aberrant mechanisms. RDoC first aims to identify reliable and valid psychological and biological mechanisms and their disruptions, with an eventual goal of understanding how anomalies in these mechanisms drive psychiatric symptoms. This approach will require new methods to ascertain samples, relying on hypothesized psychopathological mechanisms to define experimental groups instead of traditional diagnostic categories. RDoC, by design, uncouples research efforts from clinically familiar categories to focus directly on fundamental mechanisms of psychopathology. RDoC proposes a matrix of domains and levels of analyses and invites the field to test and refine the framework. If RDoC is successful, the domains will ultimately relate to familiar psychopathologies in ways that promote new knowledge regarding etiology and more efficient development of new preventive and treatment interventions.

Objective: The purpose of this study was to describe the clinical characteristics of a novel group of patients with obsessive-compulsive disorder (OCD) and tic disorders, designated as pediatric autoimmune neuropsychiatric disorders associated with streptococcal (group A β-hemolytic streptococcal [GABHS]) infections (PANDAS). Method: The authors conducted a systematic clinical evaluation of 50 children who met all of the following five working diagnostic criteria: presence of OCD and/or a tic disorder, prepubertal symptom onset, episodic course of symptom severity, association with GABHS infections, and association with neurological abnormalities. Results: The children's symptom onset was acute and dramatic, typically triggered by GABHS infections at a very early age (mean=6.3 years, SD=2.7, for tics; mean=7.4 years, SD=2.7, for OCD). The PANDAS clinical course was characterized by a relapsingremitting symptom pattern with significant psychiatric comorbidity accompanying the exacerbations; emotional lability, separation anxiety, nighttime fears and bedtime rituals, cognitive deficits, oppositional behaviors, and motoric hyperactivity were particularly common. Symptom onset was triggered by GABHS infection for 22 (44%) of the children and by pharyngitis (no throat culture obtained) for 14 others (28%). Among the 50 children, there were 144 separate episodes of symptom exacerbation; 45 (31%) were associated with documented GABHS infection, 60 (42%) with symptoms of pharyngitis or upper respiratory infection (no throat culture obtained), and six (4%) with GABHS exposure. Conclusions: The working diagnostic criteria appear to accurately characterize a homogeneous patient group in which symptom exacerbations are triggered by GABHS infections. The identification of such a subgroup will allow for testing of models of pathogenesis, as well as the development of novel treatment and prevention strategies. (Reprinted with permission from the American Journal of Psychiatry 1998; 155:264-271)

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In this report we describe the outcome of a consensus meeting that occurred at the National Institutes of Health in Bethesda, Maryland, March 12 through 14, 2005. The meeting brought together 39 specialists from multiple clinical and research disciplines including developmental pediatrics, neurology, neurosurgery, orthopedic surgery, physical therapy, occupational therapy, physical medicine and rehabilitation, neurophysiology, muscle physiology, motor control, and biomechanics. The purpose of the meeting was to establish terminology and definitions for 4 aspects of motor disorders that occur in children: weakness, reduced selective motor control, ataxia, and deficits of praxis. The purpose of the definitions is to assist communication between clinicians, select homogeneous groups of children for clinical research trials, facilitate the development of rating scales to assess improvement or deterioration with time, and eventually to better match individual children with specific therapies. "Weakness" is defined as the inability to generate normal voluntary force in a muscle or normal voluntary torque about a joint. "Reduced selective motor control" is defined as the impaired ability to isolate the activation of muscles in a selected pattern in response to demands of a voluntary posture or movement. "Ataxia" is defined as an inability to generate a normal or expected voluntary movement trajectory that cannot be attributed to weakness or involuntary muscle activity about the affected joints. "Apraxia" is defined as an impairment in the ability to accomplish previously learned and performed complex motor actions that is not explained by ataxia, reduced selective motor control, weakness, or involuntary motor activity. "Developmental dyspraxia" is defined as a failure to have ever acquired the ability to perform age-appropriate complex motor actions that is not explained by the presence of inadequate demonstration or practice, ataxia, reduced selective motor control, weakness, or involuntary motor activity.