Dear Colleagues,
It is my pleasure to welcome you to the fourth issue of 2011.
Hannah J. Broadbent and colleagues present a review article. The aim was to examine the reporting of blinding success in randomised sham-controlled trials (RCTs) of repetitive Transcranial Magnetic Stimulation (rTMS) applied to the dorsolateral prefrontal cortex. Thirteen out of 96 (13.5%) RCTs reported blinding success. Available data from nine of 13 studies showed that participants in real and sham rTMS groups were not significantly different in their ability to correctly guess their intervention allocation, but with a trend for participants in the real group to more often guess correctly. However, participants in the real rTMS groups were significantly more likely to think they had received real rTMS compared with those in sham rTMS groups.
Rüdiger J. Seitz and colleagues reviewed the current discussed on the neuroscientific basis of psychiatric diseases and the recent studies in functional neuroimaging and systems physiology on mental functions of the human brain. The findings are conceptualized as starting points for a neuroscience-based diagnosis and treatment of brain diseases at the border of psychiatry and neurology. The authors propose that brain functional units are organized in modular networks. Modular networks allow for flexibility within the modular processing units and across interconnected modules affording optimization of task performance and deficit compensation in disease.
Johannes C. Ahrendts and German colleagues present an original investigation which aimes to clarify the involvement of prefronto-striatal and posterior parietal areas in adult Attention Deficit Hyperactivity Disorder (ADHD). Voxel-based morphometry of high resolution MRI scans was applied to analyze volumetric brain differences between 31 adult patients with ADHD and 31 control subjects. The results show that ADHD patients displayed a significant reduction of gray matter volume bilaterally in the early visual cortex which supports the notion that executive dysfunction may not be the dominant neurobiological characteristic of ADHD at least in adult patients.
Neuroimaging studies have shown abnormal task-related deactivations during working memory (WM) in schizophrenia patients with recent emphasis on brain regions within the default mode network. Using fMRI, Ayna B. Nejad and colleagues from Denmark tested whether schizophrenia patients who are also antipsychotic-naïve were impaired at deactivating brain regions that do not subserve WM. Twenty-three antipsychotic-naïve patients with first-episode schizophrenia and 35 healthy individuals were included for this study. The results revealed that patients deactivated default mode network regions to a similar degree as controls. However, patients were impaired in deactivating large bilateral clusters centered on the superior temporal gyrus with increasing WM load.
Elzbieta Paszynska and colleagues investigated whether vomiting bulimic and/or non-bulimic depressive patients, both treated with a serotonin reuptake inhibitor (fluoxetine), have changes in their whole salivary secretion and inorganic components: Na+, K+, Ca2+. A total of 108 female subjects were included in this study. The findings support the hypothesis that salivary flow is an unreliable indicator of bulimia, the lack of increase in sodium level in stimulated saliva in bulimic subjects could be a more reliable confirmation of the eating disorder.
Ying-Jay Liou and colleagues from Taiwan examined the associations between genetic variations in the human PAWR gene and major depressive disorder (MDD) as well as the response to antidepressant treatment. A total of 602 patients diagnosed with MDD and 543 healthy controls wer included in this study. Genetic variations in the PAWR gene are related to susceptibility to MDD but not to SSRI treatment response. Neither single-marker nor haplotype-based analyses suggested an association between the studied markers and SSRI treatment response.
Somatoform disorder patients demonstrate a disturbance in the balance between internal and external information processing, with a decreased focus on external stimulus processing. Moritz de Greck and colleagues investigated brain activity of somatoform disorder patients, during the processing of rewarding external events, paying particular attention to the effects of inpatient multimodal psychodynamic psychotherapy. The results suggest that diminished responsiveness of brain regions involved in the processing of external stimuli underlies the disturbed balance of internal and external processing of somatoform disorder patients. By providing new approaches to cope with distressing events, multimodal psychodynamic psychotherapy led to decreased symptoms and normalization of neuronal activity.
Alexandra Schosser and colleagues present a brief report in which they aimed to replicate findings identifiying a bipolar disorder (BPB) susceptibility region on chromosome 3q20 in an independent case–control sample collected in London and Vienna. No genotypic and/or allelic association, as well as no haplotypic association, was found for any single nucleotide polymorphisms (SNP) after multiple testing correction. However, the authors cannot exclude the possibility that the sample might not have the power to detect rare variants associated with susceptibility to BPD.
Yours sincerely,