Faculty Bibliography

Active contour segmentation and its robust implementation using level sets have been studied thoroughly in the medical image analysis literature. Despite the availability of these powerful methods, clinical research still largely relies on manual slice-by-slice outlining for anatomical structure segmentation. To bridge the gap between methodological advances and clinical routine, we developed ITK-SNAP: an open source application intended to make level set segmentation easily accessible to a wide range of users with various levels of mathematical expertise. We briefly describe this new tool and report the results of a validation study in which ITK-SNAP was compared to manual segmentation of the caudate in the context of an ongoing child neuroimaging autism study

Fear and anxiety represent emotions that have captured the minds of the public for as long as artists and philosophers have been commenting on the most troubling problems confronting human beings. No doubt, this fascination relates to the ubiquity of anxiety and the great toll that it takes on many individuals: As any person who has experienced the grip of anxiety firsthand can attest, anxiety disorders bring a level of suffering that warrants considerable attention from both a clinical and research perspective. Four major insights have crystallized in recent research on pediatric anxiety disorders, each of which is echoed in papers within this special section. Two papers in the special section address issues relevant to risk for anxiety. While each of the seven papers in this special section illustrates the diversity of research conducted during the past decade, these reports clearly raise as many questions as they answer. One can only hope that studies over the next 10 years, by capitalizing on methodological advances allowing us to assess functional aspects of the human fear circuit, will address the many pressing questions raised by studies conducted over the prior 10 years.

The stimulants have been the mainstay of pharmacologic treatment for over fifty years. Methylphenidate is the most frequently prescribed of the stimulant agents. In the past, one of the main drawbacks of these agents was the abbreviated duration of action. Over the last few years three longer acting methylphenidate preparations have been released to the market. Though all these agents contain the same chemical compound they do vary in a number of ways. In this article we will present how the formulations compare in their technology and the differences in their delivery systems. We will also compare the available literature that focus on head to head comparisons in terms of pharmacokinetics studies and those reports that present efficacy data. Finally, we will suggest based on a theoretical framework on how to approach selecting an agent based on the results of these trials and the individual needs of the patient

In a multisite study of 351 children with autism spectrum disorders, 21 children with developmental delays, and 31 children with typical development, this study used caregiver interviews (i.e., the Autism Diagnostic Interview-Revised) at the time of entry into other research projects and follow-up telephone interviews designed for this project to describe the children's early acquisition and loss of social-communication milestones. Children who had used words spontaneously and meaningfully and then stopped talking were described by their caregivers as showing more gestures, greater participation in social games, and better receptive language before the loss and fewer of these skills after the loss than other children with autism spectrum disorders. A significant minority of children with autism without word loss showed a very similar pattern of loss of social-communication skills, a pattern not observed in the children with developmental delays or typical development

OBJECTIVE: Heart rate variability (HRV) reflects functioning of the autonomic nervous system and possibly also regulation by the neural limbic system, abnormalities of which have both figured prominently in various etiological models of schizophrenia, particularly those that address patients' vulnerability to stress in connection to psychosis onset and exacerbation. This study provides data on cardiac functioning in a sample of schizophrenia patients that were either medication free or on atypical antipsychotics, as well as cardiac data on matched healthy controls. We included a medication-free group to investigate whether abnormalities in HRV previously reported in the literature and associated with atypical antipsychotics were solely the effect of medications or whether they might be a feature of the illness (or psychosis) itself. METHOD: We collected 24-hour ECGs on 19 patients and 24 controls. Of the patients, 9 were medication free and 10 were on atypical antipsychotics. All subject groups were matched for age and gender. Patient groups showed equivalent symptom severity and type, as well as duration of illness. We analyzed the data using nonlinear complexity (symbolic dynamic) HRV analyses as well as standard and relative spectral analyses. RESULTS: For the medication-free patients as compared to the healthy controls, our data show decreased R-R intervals during sleep, and abnormal suppression of all frequency ranges, but particularly the low frequency range, which persisted even after adjusting the spectral data for the mean R-R interval. This effect was exacerbated for patients on atypical antipsychotics. Likewise, nonlinear complexity analysis showed significantly impaired HRV for medication-free patients that was exacerbated in the patients on atypical antipsychotics. CONCLUSIONS: Altogether, the data suggest a pattern of significantly decreased cardiac vagal function of patients with schizophrenia as compared to healthy controls, apart from and beyond any differences due to medication side effects. The data additionally confirm earlier reports of a deleterious effect of atypical antipsychotics on HRV, which may exacerbate an underlying vulnerability in patients. These results support previous evidence that autonomic abnormalities may be a core feature of the illness (or psychosis), and that an even more conservative approach to cardiac risk in schizophrenia than previously thought may therefore be clinically appropriate