Timo D. Vloet

Morphometric brain abnormalities in boys with conduct disorder.

OBJECTIVE Children with the early-onset type of conduct disorder (CD) are at high risk for developing an antisocial personality disorder. Although there have been several neuroimaging studies on morphometric differences in adults with antisocial personality disorder, little is known about structural brain aberrations in boys with CD. METHOD Magnetic resonance imaging and voxel-based morphometry were used to assess abnormalities in gray matter volumes in 23 boys ages 12 to 17 years with CD (17 comorbid for attention-deficit/hyperactivity disorder) in comparison with age- and IQ-matched controls. RESULTS Compared with healthy controls, mean gray matter volume was 6% smaller in the clinical group. Compared with controls, reduced gray matter volumes were found in the left orbitofrontal region and bilaterally in the temporal lobes, including the amygdala and hippocampus on the left side in the CD group. Regression analyses in the clinical group indicated an inverse association of hyperactive/impulsive symptoms and widespread gray matter abnormalities in the frontoparietal and temporal cortices. By contrast, CD symptoms correlated primarily with gray matter reductions in limbic brain structures. CONCLUSIONS The data suggest that boys with CD and comorbid attention-deficit/hyperactivity disorder show brain abnormalities in frontolimbic areas that resemble structural brain deficits, which are typically observed in adults with antisocial behavior.

Emotional Processing in Male Adolescents with Childhood-Onset Conduct Disorder.

BACKGROUND Boys with early onset of conduct disorder (CD), most of whom also meet diagnostic criteria of a comorbid attention deficit hyperactivity disorder (ADHD), tend to exhibit high levels of aggression throughout development. While a number of functional neuroimaging studies on emotional processing have been performed in antisocial adults, little is known about how CD children process emotional information. METHOD Functional magnetic resonance imaging data were analyzed in 22 male adolescents aged 12 to 17 years with childhood-onset CD (16 of them with comorbid ADHD) compared to 22 age-matched male healthy controls. In order to consider the likely confounding of results through ADHD comorbidity, we performed a supplementary study including 13 adolescent subjects with pure ADHD who were compared with healthy controls. To challenge emotional processing of stimuli, a passive viewing task was applied, presenting pictures of negative, positive or neutral valence. RESULTS When comparing CD/combined disorder patients with healthy controls, we found enhanced left-sided amygdala activation in response to negative pictures as compared to neutral pictures in the patient group. In addition, these boys exhibited no reduced activation in the orbitofrontal, anterior cingulate and insular cortices. By contrast, children with pure ADHD did not show any abnormalities in amygdala activation but showed decreased neural activity in the insula only in response to negative pictures. CONCLUSIONS Increased rather than reduced amygdala activation found in our study may indicate an enhanced response to environmental cues in adolescents with early-onset CD (most of whom also met the condition of ADHD), and is not consistent with the assumption of a reduced capacity to take note of affective information in the social environment. Further studies with an emphasis on developmental aspects of affect regulation are needed to clarify the relationship between CD and adult personality pathology associated with different modes of persistent antisocial behavior.

Cerebral dysfunctions of emotion-cognition interactions in adolescent-onset schizophrenia.

OBJECTIVE Schizophrenia is among the most severe of psychiatric disorders, leading to impairments of affective and cognitive abilities. These dysfunctions affect each other mutually. Adolescent-onset schizophrenia (AOS) constitutes a particularly severe form of the disorder. In this study, possible dysfunctions of the neural correlates underlying the interaction of negative emotion and working memory in AOS were investigated. METHOD During functional magnetic resonance imaging, 12 patients with AOS and 12 non-AOS adolescents performed a verbal n-back task. Intermittently, negative and neutral emotions were induced by olfactory stimulation. Group differences in working memory, emotion, and their interaction were evaluated. RESULTS In patients with AOS, lower performance sensitivity was observed, along with dorsolateral prefrontal, anterior cingulate, and inferior parietal hypoactivation during working memory demands. For negative versus neutral emotion induction, patients with AOS mainly showed increased brain activation compared with control subjects in widespread brain regions including the left orbitofrontal cortex and the medial frontal gyrus. Finally, during the interaction of emotion and cognition, altered patterns of activation in patients with AOS were found in the thalamocortical network, including the angular and the middle cingulate gyri extending to the precuneus. These activation differences were further decomposed by parameter estimates. CONCLUSIONS Our results provide new insights into the neural correlates underlying the mutual influence of affective and cognitive symptoms in AOS. During the n-back task, areas typically associated with working memory performance were found hypoactivated in patients relative to the control subjects, including the dorsolateral prefrontal and parietal cortex and the anterior cingulate. However, patients with AOS mainly demonstrated increased activation in key areas of emotion processing, such as the left orbitofrontal cortex and medial frontal areas, during negative emotion induction. A dysfunctional thalamocortical network during the interaction mainly included regions involved in the integration of converging information--either on the subcortical (thalamus) or on a higher-order cortical level (comprising the angular gyrus). These findings point to dysfunctional emotion-cognition interactions in AOS, which may explain its poor prognosis.

Ätiologie und Verlauf kindlichen dissozialen Verhaltens - Risikofaktoren für die Entwicklung einer antisozialen Persönlichkeitsstörung

Zusammenfassung: Gegenstand: Storungen des Sozialverhaltens gehoren zu den haufigsten Erkrankungen in unserem Fachgebiet. Methode: Die an der Entstehung von Storungen des Sozialverhaltens wesentlich beteiligten biologischen und psychosozialen Faktoren sowie deren Interaktion werden in dieser Ubersichtsarbeit dargestellt. Dabei wird speziell auf Veranderungen der autonomen Reagibilitat eingegangen. Ergebnis: Bei den unterschiedlichen Entwicklungspfaden hin zu einer antisozialen Personlichkeitsstorung kommt fruhen Formen von Storungen des Sozialverhaltens und dem psychopathischen Subtyp eine besondere Aussagekraft zu. Schlussfolgerung: Es wird die Bedeutung einer fruhzeitigen Forderung gefahrdeter Kinder zur Vermeidung einer dissozialen Entwicklung herausgestellt.

Attentional functions in children and adolescents with ADHD, depressive disorders, and the comorbid condition.

BACKGROUND Attention-deficit hyperactivity disorder (ADHD) and depressive disorders (DDs) often co-occur in children and adolescents, but evidence on the respective influence of these disorders on attention parameters is inconsistent. This study examines the influence of DDs on ADHD in a model-oriented approach that includes selectivity and intensity attention parameters. METHODS Ten- to fifteen-year-olds with ADHD (n=63), DDs (n=61), ADHD+DDs (n=64), and healthy controls (n=64) completed a battery of tests including five neuropsychological tasks (i.e., alertness, sustained attention, divided attention, go/no-go, and attentional set-shifting). RESULTS All clinical groups showed attentional problems, especially in more complex attentional tasks and in the intensity aspects of attention. We observed the most severe attentional impairments in children with ADHD that was independent from a comorbid DD. CONCLUSION The clinical groups were significantly different from the healthy control group, especially in more complex attentional tasks and in the intensity aspects of attention. Some differences between ADHD, DDs and ADHD+DDs groups were detected on neuropsychological attentional performance, but the effects were not strong enough to differentiate the clinical groups from each other.

Effects of the DRD4 genotype on neural networks associated with executive functions in children and adolescents

Highlights ▸ Dopamine is essential for executive functioning. ▸ 7-repeat allele of the DRD4-48 base pair repeat gene leads to sub-sensitive postsynaptic D4 receptor. ▸ We investigated effects of genotype on executive functions with fMRI in children. ▸ 7-repeat allele influences brain activation patterns and connectivity patterns.

Group Psychoeducation for Parents of Adolescents with Eating Disorders: The Aachen Program

Family-based treatment in adolescents and individual psychoeducation in adults are accepted components in a multimodal treatment of eating disorders. However, only few studies have been conducted on the use of parent-based psychoeducation. This paper presents the structure and content, as well as a preliminary evaluation, of a group psychoeducation program for parents of adolescent patients with eating disorders. The program is limited to five 90-minute sessions and aimed at increasing the parents’ understanding of the disorder and promoting high transparency with regard to our treatment principles. The vast majority of parents rated the group psychoeducation as helpful in coping with their childs disorder and would recommend others to take part in the program. This work was supported by a grant of the Christina Barc Foundation (Essen, Germany).

Reduced Cortisol in Boys with Early-Onset Conduct Disorder and Callous-Unemotional Traits

Background. A growing body of evidence suggests an association between altered hypothalamic-pituitary-adrenal axis reactivity and the development of persistent antisocial behavior in children. However the effects of altered cortisol levels remain poorly understood in the complex context of conduct disorder, callous-unemotional (CU) personality traits, and frequent comorbidities, such as attention deficit hyperactivity disorder (ADHD). The aim of the current study was to investigate associations among CU traits, antisocial behavior, and comorbid ADHD symptomatology with cortisol levels in male children and adolescents. Methods. The study included 37 boys with early-onset conduct disorder (EO-CD, mean age 11.9 years) and 38 healthy boys (mean age 12.5 years). Participants were subjected to multiple daytime salivary cortisol measurements and a psychometric characterization. Results. Subjects in the EO-CD group with elevated CU traits showed a diminished cortisol awakening response compared to healthy participants. In the EO-CD group, high CU traits and impulsivity were associated with decreased diurnal cortisol levels, while associations with antisocial behavior were not detected. The cortisol awakening response was significantly inversely associated with hyperactivity (P = 0.02) and marginally significant with CU traits (P = 0.07). Conclusions. These results indicate a specific association between CU traits and a diminished stress response, which is not explained by antisocial behavior in general.

ADHD and delinquency--a developmental perspective.

Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders of childhood and adolescence. Until now, it has been unclear whether ADHD by itself constitutes a risk factor for later delinquency or does so only in combination with other disruptive symptoms. This article seeks to give a comprehensive account of the literature to shed light on the developmental pathway from childhood ADHD to adult criminality. Comorbid ADHD and conduct disorder (CD) are significantly related to a range of biological and environmental risk factors such as neurocognitive impairment, high parental psychopathology, poor social functioning, and other comorbid mental disorders, particularly substance abuse, that are described in this review. In addition, the results of treatment studies are presented, with a special focus on the results of the Multimodal Treatment Study of Children with ADHD (MTA). Although treatment programs, including medication and psychosocial treatment, can be very effective in improving the functioning of children with ADHD in the social and academic domains in the short term, there is no conclusive evidence that such treatments lower the risk for developing delinquency in adulthood.

Getting the phenotypes right: an essential ingredient for understanding aetiological mechanisms underlying persistent violence and developing effective treatments

In order to reduce societal levels of violence, it is essential to advance understanding of the neurobiological mechanisms involved in initiating and maintaining individual patterns of physical aggression. New technologies such as Magnetic Resonance Imagining and analyses of DNA provide tools for identifying these mechanisms. The reliability and validity of the results of studies using these tools depend not only on aspects of the technology, but also on the methodological rigour with which the studies are conducted, particularly with respect to characterizing the phenotype. The present article discusses five challenges confronting scientists who aim to advance understanding of the neurobiological mechanisms associated with persistent violence. These challenges are: (1) to develop evidence-based hypotheses and to design studies that test alternate hypotheses; (2) to recruit samples that are homogeneous with respect to variables that may be linked to neurobiological mechanisms underpinning violent behaviour; (3) to use reliable and valid measures in order to fully characterize participants so that the external validity of the results is evident; (4) to restrict the range of age of participants so as not to confuse developmental change with group differences; and (5) to take account of sex. Our goal is to contribute to elevating methodological standards in this new field of research and to thereby improve the validity of results and move closer to finding effective ways to reduce violence.