Increased regional Hurst exponent reflects response inhibition related neural complexity alterations in pediatric bipolar disorder patients during an emotional Go-Nogo task.

Fractal patterns have been shown to change in resting- and task-state blood oxygen level-dependent signals in bipolar disorder patients. However, fractal characteristics of brain blood oxygen level-dependent signals when responding to external emotional stimuli in pediatric bipolar disorder remain unclear. Blood oxygen level-dependent signals of 20 PBD-I patients and 17 age- and sex-matched healthy controls were extracted while performing an emotional Go-Nogo task. Neural responses relevant to the task and Hurst exponent of the blood oxygen level-dependent signals were assessed. Correlations between clinical indices and Hurst exponent were estimated. Significantly increased activations were found in regions covering the frontal lobe, parietal lobe, temporal lobe, insula, and subcortical nuclei in PBD-I patients compared to healthy controls in contrast of emotional versus neutral distractors. PBD-I patients exhibited higher Hurst exponent in regions that involved in action control, such as superior frontal gyrus, inferior frontal gyrus, inferior temporal gyrus, and insula, with Hurst exponent of frontal orbital gyrus correlated with onset age. The present study exhibited overactivation, increased self-similarity and decreased complexity in cortical regions during emotional Go-Nogo task in patients relative to healthy controls, which provides evidence of an altered emotional modulation of cognitive control in pediatric bipolar disorder patients. Hurst exponent may be a fractal biomarker of neural activity in pediatric bipolar disorder.

The Clinical Features of Comorbid Pediatric Bipolar Disorder in Children with Autism Spectrum Disorder.

The aim of this study was to describe clinical features of PBD comorbidity in children with ASD. Forty children with ASD and PBD aged 6-18 years, and 40 age- and sex-matched ASD subjects with no affective episodes were included in the study. Autism Behavior CheckList, Abberant Behavior CheckList, and Young Mania Rating Scale-Parent Version were completed. This study shows that PBD comorbidity in children with ASD involves a highly episodic course, with manic episodes, subsyndromal symptoms and interepisodic periods commonly being described in the manic symptom profile of these children. These findings need to be repeated with large samples, together with controlled studies concerning therapeutic interventions directed toward PBD comorbidity in children with ASD.

A comparison of bipolar disorders in children in Italy and the United States.

BACKGROUND: The clinical presentation of bipolar disorders, though clearly recognized in adolescents, remains controversial in younger children and across cultures. The aim of this study was to compare the clinical presentation of bipolar disorders in Italian and American children between ages 5 and 12 years. METHODS: Sixty-seven children from six outpatient programs were enrolled (Italian sample: n=40; American sample: n=28) between January 2010 and June 2011. Children and their parents were interviewed by experienced clinicians using the Washington University in St. Louis Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present, Lifetime Version (WASH-U K-SADS). RESULTS: Italian children scored significantly higher on ratings of "elevated mood" (p=0.002), whereas American children scored significantly higher on ratings of "flight of ideas" (p=0.001) and "productivity" (p=0.001). Rates of comorbidity were different between groups. LIMITATIONS: Data were acquired from several sites in Italy as compared to from a single American site. Medication and educational information were not systematically collected. Furthermore, the sample collected may only reflect characteristics of a less severely ill group of bipolar children. CONCLUSIONS: Our comparison of Italian and American children with early onset bipolar disorders found that the phenotype of bipolar spectrum disorders is largely shared across cultures, although psychiatric comorbidities differed.