Brain structure in post-traumatic stress disorder A voxel-based morphometry analysis

This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, using the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter volume was the highest in the trauma control group, followed by the symptoms-improved group, and the lowest in the chronic post-traumatic stress disorder group. Compared with the symptoms-improved group, the gray matter volume in the lingual gyrus of the right occipital lobe was reduced in the chronic post-traumatic stress disorder group. Compared with the trauma control group, the gray matter volume in the right middle occipital gyrus and left middle frontal gyrus was reduced in the symptoms-improved group. Compared with the trauma control group, the gray matter volume in the left superior parietal lo- bule and right superior frontal gyrus was reduced in the chronic post-traumatic stress disorder group. The gray matter volume in the left superior parietal Iobule was significantly positively correlated with the State-Trait Anxiety Inventory subscale score in the symptoms-improved group and chronic post-traumatic stress disorder group （r = 0.477, P = 0.039）. Our findings indicate that （1） chronic post-traumatic stress disorder patients have gray matter structural damage in the prefrontal lobe, oc- cipital lobe, and parietal lobe, （2） after post-traumatic stress, the disorder symptoms are improved and gray matter structural damage is reduced, but cannot recover to the trauma-control level, and （3） the superior parietal Iobule is possibly associated with chronic post-traumatic stress disorder. Post-traumatic stress disorder patients exhibit gray matter abnormalities.

Decreased frontal lobe function in people with Internet addiction disorder

In our previous studies, we showed that frontal lobe and brainstem functions were abnormal in online game addicts. In this study, 14 students with Internet addiction disorder and 14 matched healthy controls underwent proton-magnetic resonance spectroscopy to measure cerebral function. Results demonstrated that the ratio of N-acetylaspartate to creatine decreased, but the ratio of cho- line-containing compounds to creatine increased in the bilateral frontal lobe white matter in people with Internet addiction disorder. However, these ratios were mostly unaltered in the brainstem, suggesting that frontal lobe function decreases in people with Internet addiction disorder.

Testing the role of genetic variation of the MC4R gene in Chinese population in antipsychotic-induced metabolic disturbance

Antipsychotic-induced metabolic disturbance(AIMD) is a common adverse effect of antipsychotics with genetics partly underpinning variation in susceptibility among schizophrenia patients. Melanocortin4 receptor(MC4 R) gene, one of the candidate genes for AIMD, has been under-studied in the Chinese patients. We conducted a pharmacogenetic study in a large cohort of Chinese patients with schizophrenia. In this study, we investigated the genetic variation of MC4 R in Chinese population by genotyping two SNPs(rs489693 and rs17782313) in 1,991 Chinese patients and examined association of these variants with the metabolic effects that were often observed to be related to AIMD. Metabolic measures, including body mass index(BMI), waist circumference(WC), glucose, triglyceride, high-density lipoprotein(HDL), and low-density lipoprotein(LDL) levels were assessed at baseline and after 6-week antipsychotic treatment. We found that interaction of SNP×medication status(drug-na?ve/medicated) was significantly associated with BMI, WC, and HDL change %, respectively. Both SNPs were significantly associated with baseline BMI and WC in the medicated group. Moderate association of rs489693 with WC, Triglyceride, and HDL change % were observed in the whole sample. In the drug-na?ve group, we found recessive effects of rs489693 on BMI gain more than 7%, WC and Triglyceride change %, with AA incurring more metabolic adverse effects. In conclusion, the association between rs489693 and the metabolic measures is ubiquitous but moderate. Rs17782313 is less involved in AIMD. Two SNPs confer risk of AIMD to patients treated with different antipsychotics in a similar way.

Grey matter volume abnormalities in patients with bipolar I depressive disorder and unipolar depressive disorder:a voxelbased morphometry study

Bipolar disorder and unipolar depressive disorder（UD） may be different in brain structure. In the present study,we performed voxel-based morphometry（VBM） to quantify the grey matter volumes in 23 patients with bipolar I depressive disorder（BP1） and 23 patients with UD,and 23 age-,gender-,and educationmatched healthy controls（HCs） using magnetic resonance imaging. We found that compared with the HC and UD groups,the BP1 group showed reduced grey matter volumes in the right inferior frontal gyrus and middle cingulate gyrus,while the UD group showed reduced volume in the right inferior frontal gyrus compared to HCs. In addition,correlation analyses revealed that the grey matter volumes of these regions were negatively correlated with the Hamilton depression rating scores. Taken together,the results of our study suggest that decreased grey matter volume of the right inferior frontal gyrus is a common abnormality in BP1 and UD,and decreasedgrey matter volume in the right middle cingulate gyrus may be specifi c to BP1.

Altered regional homogeneity in post-traumatic stress disorder: a resting-state functional magnetic resonance imaging study

Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder （PTSD）. Comparison of the resting-state patterns of intrinsic functional synchronization, as measured by functional magnetic resonance imaging （fMRI）, between groups with and without PTSD following a traumatic event can help identify the neural mechanisms of the disorder and targets for intervention. Methods Fifty-four PTSD patients and 72 matched traumatized subjects who experienced the 2008 Sichuan earthquake were imaged with blood oxygen level-dependent （BOLD） fMRI and analyzed using the measure of regional homogeneity （ReHo） during the resting state. Results PTSD patients presented enhanced ReHo in the left inferior parietal lobule and right superior frontal gyrus, and reduced ReHo in the right middle temporal gyrus and lingual gyrus, relative to traumatized individuals without PTSD. Conclusion Our findings showed that abnormal brain activity exists under resting conditions in PTSD patients who had been exposed to a major earthquake. Alterations in the local functional connectivity of cortical regions are likely to contribute to the neural mechanisms underlying PTSD.

Interaction Between Variations in Dopamine D2 and Serotonin 2A Receptor is Associated with Short-Term Response to Antipsychotics in Schizophrenia

Dear Editor,Schizophrenia is a chronic and debilitating brain disorder,which has a strong genetic component with heritability ranging from 66%to 85%[1,2].Currently,antipsychotic drugs remain the most effective treatment for the psychotic symptoms of schizophrenia[3].Because of the severe sideeffects of first-generation antipsychotics(FGAs),secondgeneration antipsychotics(SGAs)have become more widely used in the treatment of schizophrenia.

Altered functional connectivity networks of hippocampal subregions in remitted late-onset depression:a longitudinal resting-state study

The regional specifi city of hippocampal abnormalities in late-life depression（LLD） has been demonstrated in previous studies. In this study,we sought to examine the functional connectivity（FC） patterns of hippocampal subregions in remitted late-onset depression（r LOD）,a special subtype of LLD. Fourteen r LOD patients and 18 healthy controls underwent clinical and cognitive evaluations as well as resting-state functional magnetic resonance imaging scans at baseline and at ~21 months of follow-up. Each hippocampus was divided into three parts,the cornu ammonis（CA）,the dentate gyrus,and the subicular complex,and then six seed-based hippocampal subregional networks were established.Longitudinal changes of the six networks over time were directly compared between the rL OD and control groups. From baseline to follow-up,the r LOD group showed a greater decline in connectivity of the left CA to the bilateral posterior cingulate cortex/precuneus（PCC/PCUN）,but showed increased connectivity of the right hippocampal subregional networks with the frontal cortex（bilateral medial prefrontal cortex/anterior cingulate cortex and supplementary motor area）. Further correlative analyses revealed thatthe longitudinal changes in FC between the left CA and PCC/PCUN were positively correlated with longitudinal changes in the Symbol Digit Modalities Test（r = 0.624,P = 0.017） and the Digit Span Test（r = 0.545,P = 0.044） scores in the r LOD group. These results may provide insights into the neurobiological mechanism underlying the cognitive dysfunction in r LOD patients.

An update on research and approaches in biological psychiatry

Many studies have shown that,in terms of global burden,mental disorders have exceeded diseases of the cardiovascular and respiratory systems as well as malignant tumors.Nevertheless,the pathological mental activities caused by the millions of neurons in the human brain are far less clear than diseases of other organs and systems.This is not only due to the limited approaches to exploring the human brain,but also the multiple mechanisms by