Kamiya et alArticle report 2 lines of evidence that support a role for the centrosome in the pathology of schizophrenia. Biological data indicate a centrosomal pathway that includes the PCM1, DISC1, and BBS proteins playing a role in proper cortical development. Genetic data further confirm the notion that PCM1 is a risk factor for schizophrenia by providing a nonsense mutation that segregates with schizophrenia spectrum psychosis in a pedigree.
Hong et alArticle use a signal processing technique called discrete wavelet to decompose auditory brain waves into different frequency bands. Their results show that gating of the θ-α frequency band responses is significantly impaired in people with schizophrenia and in their first-degree relatives and is highly heritable. These findings suggest that inability to sufficiently suppress θ-α activates may reflect the underlying biological process of abnormal sensory gating in schizophrenia.
Kempton et alArticle conducted a meta-analysis of 98 structural imaging studies in bipolar disorder, revealing robust but regionally nonspecific changes of brain structure, with lithium medication being associated with increased gray matter volume. The authors conclude that studies will remain underpowered unless sample size is increased or improvements in phenotypic selection and imaging methods are made.
Frans et alArticle examined the association between advancing paternal age and bipolar disorder in a nationwide nested case-control study based on Swedish registers. Advancing paternal age monotonously increased the risk of bipolar disorder in the offspring and the paternal age effect was even more pronounced in patients with an early disorder onset.
Using tract-based spatial statistics, Versace et alArticle examined fractional anisotropy (FA) longitudinal and radial diffusivities in the white matter skeleton of individuals with bipolar disorder and healthy controls. They found greater FA in the left orbitomedial prefrontal cortex and reduced FA in the right orbitomedial prefrontal cortex in individuals with bipolar disorder vs healthy controls. This abnormal right-left asymmetry may represent a biological mechanism for mood dysregulation in bipolar disorder.
Miklowitz et alArticle examined the effectiveness of family-focused therapy and medications in 58 adolescents recovering from an episode of bipolar spectrum disorder. Adolescent patients who were randomly assigned to 21 sessions of family-focused therapy and pharmacotherapy recovered from their baseline depression symptoms faster, spent fewer weeks in depressive episodes, and had fewer severe depression symptoms over 2 years than patients assigned to 3 sessions of psychoeducation and pharmacotherapy.
Van den Oord et alArticle tested 420 000 genetic markers for their association with neuroticism in a sample of 1227 healthy subjects. The 60 most promising markers were subsequently genotyped in a replication sample comprising 1880 healthy subjects. The most promising results were for the MAMDC1 gene, where associations involved exactly the same markers and direction of effects.
Praschak-Rieder et alArticle investigated the relationship between regional serotonin transporter (5-HTT) binding and season using carbon 11–labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)-benzonitrile positron emission tomography in humans. During the darker months of the year, 5-HTT binding was elevated relative to the brighter months of the year. Since higher 5-HTT density is associated with lower synaptic serotonin levels, regulation of 5-HTT density by season is a mechanism that may explain seasonal changes in mood and behavior.
Using data collected at ages 6, 11, and 17 years on stratified samples of urban and suburban children, Bohnert and BreslauArticle found that low-birth-weight children have modest excesses of externalizing and internalizing disturbances compared with normal-birth-weight children. An increased risk of attention disturbance was associated with low birth weight only in urban children. Low birth weight effects on psychiatric disturbance were stable through the period of school attendance.
In a study of young children (N = 101, aged 18.8-45.0 months), Hoeft et alArticle show that voxel-wise multivariate morphometric patterns classify fragile X syndrome from typically developing and idiopathic developmentally delayed controls with more than 90% prediction accuracy. These findings demonstrate the feasibility and clinical importance of examining detailed spatial patterns of healthy and atypical brain development.
This Month in Archives of General Psychiatry. Arch Gen Psychiatry. 2008;65(9):991. doi:10.1001/archgenpsychiatry.2008.4