Objective Disruptive mood dysregulation disorder (DMDD), characterized by severe irritability, and attention-deficit/hyperactivity disorder (ADHD) are highly comorbid. This is the first study to characterize neural and behavioral similarities and differences in attentional functioning across these disorders. Method Twenty-seven healthy volunteers, 31 patients with DMDD, and 25 patients with ADHD (8–18-year-olds) completed a functional magnetic resonance imaging (fMRI) attention task. Group differences in intra-subject variability in reaction time (ISVRT) were examined. The current fMRI analytic approach precisely quantified trial-wise associations between reaction time and brain activity. Results Group differences manifested in the relationship between reaction time and brain activity (all regions: p<.01, F>2.54, ηp2>0.06). Patients with DMDD showed specific alterations in the right paracentral lobule, superior parietal lobule, fusiform gyrus, and cerebellar culmen. In contrast, both patients with DMDD and ADHD exhibited blunted compensatory increases in activity on long reaction time trials. Additionally, youth with DMDD exhibited increased activity in the postcentral gyrus, medial frontal gyrus, and cerebellar tonsil and declive (all regions: p<.05, F>2.46, ηp2>0.06). The groups in the imaging sample did not differ significantly in ISVRT (F[2,79]=2.664, p=.076, ηp2=0.063), though ISVRT was significantly elevated among youth with DMDD and ADHD when including those not meeting strict motion and accuracy criteria for the imaging analysis (F[2,96]=4.283, p=.017, ηp2=0.083). Conclusion Patients with DMDD exhibited specific alterations in the relationship between pre-stimulus brain activity and reaction time. Both patients with DMDD and ADHD exhibited similar blunting of compensatory neural activity in frontal, parietal, and other regions. Additionally, patients with DMDD demonstrated elevated reaction time variability relative to healthy youth. This work is the first to identify common and unique behavioral and neural signatures of DMDD and ADHD.

Background Few neuroimaging studies compare individuals affected with bipolar disorder (BP), at high familial risk for BP, and at low risk to identify endophenotypes for BP. None have examined variability in attention, despite promising behavioral work in this area. We used functional magnetic resonance imaging (fMRI) methods uniquely powered to compare the neural correlates of attention variability in these three groups. Methods The current study examined 106 8–25-year-olds who completed an fMRI attention task: 24 with BP, 29 at-risk based on a first-degree relative with BP, and 53 healthy, low-risk individuals. Group differences in intra-subject variability in reaction time were examined and a sophisticated fMRI analytic approach was used to quantify precisely trial-wise associations between reaction time and brain activity. The latter has not been examined previously in BP or risk for BP. Results Relative to healthy individuals, those with BP or at-risk for BP exhibited increased reaction time variability (F(2,102)=4.26, p=.02, ηp2=0.08). Importantly, we identified blunted relationships between trial-wise variation in reaction time and brain activity in the inferior and middle frontal gyri, precuneus, cingulate cortex, caudate, and postcentral gyrus (all regions: p<.001, ηp2>0.06) in both at-risk and BP individuals compared to healthy, low-risk individuals. This blunting partially mediated group differences in reaction time variability (β=0.010, 95% Confidence Interval=[0.002–0.020], Sobel Z=2.08, p=.038). Conclusions Blunting in key frontal, cingulate, and striatal areas was evident in unaffected, at-risk individuals and in euthymic BP patients. Elucidating such novel neural endophenotypes can facilitate new approaches to BP prediction, diagnosis, and prevention.

A number of studies have used variable-centered approaches to examine informant discrepancies on children's behavior problems; however, few such studies have used person-centered approaches to explore patterns of informant discrepancies or correlates of discrepancies in informant symptom ratings. The present study addressed these gaps by examining profiles of informant agreement on internalizing and externalizing symptoms and examining whether two important contextual factors, parenting and school engagement, are associated with profile membership. Data from an at-risk, urban sample of youth participants (N = 346, M age = 12.47 +/− 0.60 years, 56% male, and 75% Black), their caregivers, and one of their teachers were analyzed in the current study. Youth from 20 schools in a Mid-Atlantic state were screened for elevated levels of aggression and were selected to participate in the Early Adolescent Coping Power study. At baseline, youth, caregivers, and teachers reported on youth's internalizing symptoms and caregivers and teachers reported on youth's externalizing symptoms. Caregivers reported on their parenting; youth

Background-Few neuroimaging studies compare individuals affected with bipolar disorder (BP), at high familial risk for BP, and at low risk to identify endophenotypes for BP. None have examined variability in attention, despite promising behavioral work in this area. We used functional magnetic resonance imaging (fMRI) methods uniquely powered to compare the neural correlates of attention variability in these three groups.Methods-The current study examined 106 8-25-year-olds who completed an fMRI attention task: 24 with BP, 29 at-risk based on a first-degree relative with BP, and 53 healthy, low-risk individuals. Group differences in intra-subject variability in reaction time were examined and a sophisticated fMRI analytic approach was used to quantify precisely trial-wise associations between reaction time and brain activity. The latter has not been examined previously in BP or risk for BP.Results-Relative to healthy individuals, those with BP or at-risk for BP exhibited increased reaction time variability (F(2,102)=4.26, p=.02, η p 2 =0.08). Importantly, we identified blunted relationships between trial-wise variation in reaction time and brain activity in the inferior and middle frontal gyri, precuneus, cingulate cortex, caudate, and postcentral gyrus (all regions: p<. 001, η p 2 >0.06) in both at-risk and BP individuals compared to healthy, low-risk individuals. This