ASSOCIATION ANALYSIS OF SEROTONIN TRANSPORTER PROMOTER GENE POLYMORPHISM WITH ADHD AND RELATED SYMPTOMATOLOGY

Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood behavioral disorders. Genetic factors contribute to the underlying liability to develop attention deficit hyperactivity disorder. Several investigations have reported associations between ADHD and serotonin transporter promoter polymorphisms, but the results have been inconsistent. The present study did not find significant association between ADHD and serotonin transporter promoter polymorphisms, but did find an effect of serotonin transporter promoter polymorphisms on some ADHD symptomatology. Patients homozygous for the short allele showed more Withdrawn or Somatic complaint scores than subjects with the long allele.     

Neural network topology in ADHD; evidence for maturational delay and default-mode network alterations

Objective

Attention-deficit/hyperactivity disorder (ADHD) has been associated with widespread brain abnormalities in white and grey matter, affecting not only local, but global functional networks as well. In this study, we explored these functional networks using source-reconstructed electroencephalography in ADHD and typically developing (TD) children. We expected evidence for maturational delay, with underlying abnormalities in the default mode network.

Network connectivity abnormality profile supports a categorical‐dimensional hybrid model of ADHD

Attention‐deficit/hyperactivity disorder (ADHD) is characterized by inattention, hyperactivity, and impulsivity, but there is no consensus regarding whether ADHD exists on the extreme end of a continuum of normal behavior or represents a discrete disorder. In this study, we sought to characterize both the categorical and dimensional variations in network functional connectivity in order to identify neural connectivity mechanisms of ADHD. Functional connectivity analyses of resting‐state fMRI data from 155 children with ADHD and 145 typically developing children (TDC) defined the dorsal attention network (DA), default mode network (DM), salience processing network (SAL) and executive control network (CON). Regional alterations in connectivity associated with categorical diagnoses and dimensional symptom measures (inattention and hyperactivity/impulsivity) as well as their interaction were systematically characterized. Dimensional relationships between symptom severity measures and functional connectivity that did not differ between TDC and children with ADHD were observed for each network, supporting a dimensional characterization of ADHD. However, categorical differences in functional connectivity magnitude between TDC and children with ADHD were detected after accounting for dimensional relationships, indicating the existence of categorical mechanisms independent of dimensional effects. Additionally, differential dimensional relationships for TDC versus ADHD children demonstrated categorical differences in brain–behavior relationships. The patterns of network functional organization associated with categorical versus dimensional measures of ADHD accentuate the complexity of this disorder and support a dual characterization of ADHD etiology featuring both dimensional and categorical mechanisms. Hum Brain Mapp 35:4531–4543, 2014. © 2014 Wiley Periodicals, Inc .     

DSM‐5 OBSESSIVE‐COMPULSIVE AND RELATED DISORDERS: CLINICAL IMPLICATIONS OF NEW CRITERIA

For the publication of DSM‐5, obsessive‐compulsive disorder (OCD) was the subject of significant revisions to its classification and diagnostic criteria. One of these significant changes was the placement of OCD in a new category, “Obsessive‐Compulsive and Related Disorders (OCRDs),” which also includes body dysmorphic disorder (BDD), trichotillomania (hair‐pulling disorder), excoriation (skin‐picking) disorder, hoarding disorder, substance/medication‐induced OCRD, OCRD due to another medical condition, and other specified OCRDs. Changes in the diagnostic criteria and grouping of these disorders may have significant clinical implications, and will be reviewed in this article.