Within the human brain, a system of long-distance pathways, referred to as the “rich club,” has been proposed to play an important role in enabling efficient communication between distant parts of the neural network. In their study, van den Heuvel and colleagues show that schizophrenia involves a reduced connectivity of this centrally embedded communication backbone and that abnormal wiring of the brain’s rich club may contribute to altered brain dynamics and reduced integration of information between subsystems of the brain in patients.
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Nelson and colleagues conducted a long-term follow-up of 416 patients identified as being at “ultra high risk” of psychotic disorder. Findings indicated that participants continued to be at risk up to 10 years after entry, with a 35% rate of transition to psychotic disorder over this period. Factors associated with transition included year of entry to the clinic, duration of symptoms prior to clinic entry, baseline functioning, negative symptoms, and disorders of thought content.
Sutin and colleagues used data from a long-run longitudinal study to model the trajectory of depressive symptoms across the adult life span. Depressive symptoms were highest in young adulthood, declined across middle adulthood, and increased again at older ages. The sex difference in depressive affect seen in younger adulthood disappeared by older age. Depressive symptoms still showed an uptick in old age even after accounting for increases in comorbidity, functional limitations, and impending death.
Benros and colleagues conducted a prospective cohort study based on the entire Danish population. The study revealed that hospital contacts with an autoimmune disease or an infection increased the risk of a subsequent mood disorder by 45% and 62%, respectively. The number of autoimmune diseases, particularly infections, increased the risk of mood disorders in a dose-response relationship. These findings are compatible with an immunologic hypothesis for the development of mood disorders in subgroups of patients.
For patients with major depression, biomarkers that stratify individuals into treatment-specific subgroups are needed to better guide first-line treatment selection. McGrath and colleagues report anterior insula metabolism as a putative treatment stratification biomarker for predicting differential outcomes to escitalopram and cognitive behavior therapy. Prerandomization anterior insula hypometabolism was associated with remission to cognitive behavior therapy and poor response to escitalopram, whereas hypermetabolism characterized remission to escitalopram and nonresponse to cognitive behavior therapy, suggesting potential for such an approach.
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Within the context of the population-based Québec Longitudinal Study of Child Development (n = 1759), Herba and colleagues investigated whether early child care moderates associations between maternal depressive symptoms and child internalizing problems (emotional problems, separation anxiety symptoms, and social withdrawal symptoms) over the preschool period. Participants were assessed repeatedly between ages 5 and 60 months. Children of mothers with elevated maternal depressive symptoms and who attended regulated early child care services showed fewer internalizing problems.
Little is understood about delayed-onset posttraumatic stress disorder. In a longitudinal study of 1084 traumatic injury survivors conducted over 2 years, Bryant and colleagues observed that delayed-onset posttraumatic stress disorder may be explained in terms of ongoing stress compounding initial stress responses, as well as pointing to the role of mild traumatic brain injury in contributing to worsening stress over time.
To examine a possible effect of maternal smoking during pregnancy on the offspring’s brain functioning, Müller and colleagues compared neural reward processing between 177 adolescents who were prenatally exposed to maternal cigarette smoking and 177 matched peers. Using functional magnetic resonance imaging, they found a weaker response to reward anticipation but not to reward receipt in the ventral striatum in prenatally exposed adolescents.
Konova and colleagues investigated brain functional connectivity in individuals addicted to cocaine in a placebo-controlled, crossover study of a single dose of the indirect dopamine agonist methylphenidate. Methylphenidate modulated brain connectivity in circuits relevant to the pathophysiology of addiction and habit formation, such that the drug reduced connectivity between the ventral and dorsal striatum, a connection that was associated with the severity of addiction. Methylphenidate also strengthened several connections relevant to emotion regulation and inhibitory control.
Uddin and colleagues used functional magnetic resonance imaging to examine connectivity of large-scale brain networks and determine whether specific networks can distinguish children with autism spectrum disorder (ASD) from typically developing (TD) children. They report hyperconnectivity within several large-scale brain networks in children with ASD compared with TD children. The salience network showed the highest classification accuracy among all networks examined; this network discriminated children with ASD from TD children with a classification accuracy of 78%.
Highlights. JAMA Psychiatry. 2013;70(8):769-771. doi:10.1001/jamapsychiatry.2013.1997