Association between smaller left posterior superior temporal gyrus volume on magnetic resonance imaging and smaller left temporal P300 amplitude in first-episode schizophrenia

BACKGROUND: In chronic schizophrenia, the P300 is broadly reduced and shows a localized left temporal deficit specifically associated with reduced gray matter volume of the left posterior superior temporal gyrus (STG). In first-episode patients, a similar left temporal P300 deficit is present in schizophrenia, but not in affective psychosis. The present study investigated whether the left temporal P300-left posterior STG volume association is selectively present in first-episode schizophrenia. METHOD: P300 was recorded as first-episode subjects with schizophrenia (n = 15) or affective psychosis (n = 18) or control subjects (n = 18) silently counted infrequent target tones amid standard tones. High-resolution spoiled gradient-recalled acquisition magnetic resonance images provided quantitative measures of temporal lobe gray matter regions of interest. RESULTS: Patients with first-episode schizophrenia displayed a reversed P300 temporal area asymmetry (smaller on the left), while magnetic resonance imaging showed smaller gray matter volumes of left posterior STG relative to control subjects and patients with affective psychosis (15.4% and 11.0%, respectively), smaller gray matter volumes of left planum temporale (21.0% relative to both), and a smaller total Heschl's gyrus volume (14.6% and 21.1%, respectively). Left posterior STG and the left planum temporale, but not other regions of interest, were specifically and positively correlated (r>0.5) with left temporal P300 voltage in patients with schizophrenia but not in patients with affective psychosis or in control subjects. CONCLUSION: These results suggest that the left temporal P300 abnormality specifically associated with left posterior STG gray matter volume reduction is present at the first hospitalization for schizophrenia but is not present at the first hospitalization for affective psychosis.     

The percentage and clinical correlates of alexithymia in stable patients with schizophrenia

Alexithymia is a common, but less-recognized affective deficit in patients with schizophrenia. To date, no definitive conclusions have been drawn about the relationship between alexithymia and the clinical symptoms or their clinical correlates, particularly in stable patients with schizophrenia. The purpose of this study was to investigate the link between alexithymia and psychopathological symptoms, as well as any associated correlates, in stable patients with schizophrenia. A total of 435 Chinese patients with schizophrenia were recruited. The Positive and Negative Symptoms Scale (PANSS) was used to evaluate each patient’s psychopathological symptoms. The Toronto Alexithymia Scale (TAS-20) was used to measure alexithymia. The percentage of alexithymia was 35.2% in stable patients with schizophrenia. Compared to non-alexithymia patients, patients with alexithymia had higher PANSS total scores, negative subscores, depressive subscores, and cognitive subscores (all p < 0.05). Multivariate regression analysis revealed that the following variables were positively associated with TAS-20 total scores: PANSS negative subscores (β = 0.274, t = 3.198, p = 0.001) and PANSS depressive subscores (β = 0.366, t = 2.500, p = 0.013). Education years (β = – 0.453, t = – 2.824, p = 0.005) was negatively associated with TAS-20 total scores. Our results suggest that the percentage of alexithymia was relatively higher in stable patients with schizophrenia. Education levels, negative symptoms, and depressive symptoms were independently associated with alexithymia in this specific population.

     

首发精神分裂症额叶白质和海马氢质子波谱的非对称性异常及其治疗1年后的变化

目的探讨首发精神分裂症患者脑代谢物非对称性的改变及其受非典型抗精神病药物治疗的影响。方法对符合美国精神障碍诊断与统计手册第4版(Diagnostic and Statistical Manual of Mental Disorders,DSM-Ⅳ)诊断标准的21例首发精神分裂症患者和21名健康对照进行氢质子磁共振波谱扫描,并在治疗1年后对患者再次进行扫描,检测双侧额叶白质和海马的N-乙酰天门冬氨酸(N-Acetylaspartate,NAA)、胆碱(choline,Cho)和肌酸(creatine,Cr),以Cr为参照物,分别计算双侧NAA/Cr、Cho/Cr比值。在治疗前后对患者进行阳性和阴性量表(positive and negcotive symtoms scale,PANSS)、大体功能量表(global assessment function,GAF)评定。采用配对t检验进行脑代谢物非对称性分析。结果非对称性分析发现基线期健康对照组左侧海马NAA/Cr比右侧高[(1.41±0.09)vs.(1.32±0.10),P<0.05],首发精神分裂症组左、右侧海马代谢物比较,差异无统计学意义;而经过1年治疗后,与治疗前相比首发精神分裂症组PANSS评分显著降低(68.57±27.74vs.97.95±13.81)、GAF量表评分显著增加(58.76±23.07 vs.28.05±8.99),均P<0.05,精神分裂症组左侧海马NAA/Cr比右侧高[(1.41±0.10)vs.(1.31±0.13),P<0.05]。健康对照组及首发精神分裂症组治疗前后双侧额叶白质代谢物差异均无统计学意义(P>0.05)。结论首发精神分裂症患者海马NAA/Cr的非对称性消失,经非典型抗精神病药物治疗后,在精神症状改善的同时海马NAA/Cr的非对称性恢复。     

Increased Cerebellar Functional Connectivity With the Default-Mode Network in Unaffected Siblings of Schizophrenia Patients at Rest

The default-mode network (DMN) is vital in the neurobiology of schizophrenia, and the cerebellum participates in the high-order cognitive network such as the DMN. However, the specific contribution of the cerebellum to the DMN abnormalities remains unclear in unaffected siblings of schizophrenia patients. Forty-six unaffected siblings of schizophrenia patients and 46 healthy controls were recruited for a resting-state scan. The images were analyzed using the functional connectivity (FC) method. The siblings showed significantly increased FCs between the left Crus I and the left superior medial prefrontal cortex (MPFC), as well as between the lobule IX and the bilateral MPFC (orbital part) and right superior MPFC compared with the controls. No significantly decreased FC was observed in the siblings relative to the controls. The analyses were replicated in 49 first-episode, drug-naive patients with schizophrenia, and the results showed that the siblings and the patients shared increased FCs between the left Crus I and the left superior MPFC, as well as between the lobule IX and the left MPFC (orbital part) compared with the controls. These findings suggest that increased cerebellar-DMN connectivities emerge earlier than illness onset, which highlight the contribution of the cerebellum to the DMN alterations in unaffected siblings. The shared increased cerebellar-DMN connectivities between the patients and the siblings may be used as candidate endophenotypes for schizophrenia.Key words: unaffected siblings of schizophrenia patients, schizophrenia, cerebellum, functional connectivity, default-mode network     

Reduced paralimbic system gray matter volume in schizophrenia: Correlations with clinical variables,symptomatology and cognitive function

BackgroundPsychopathy is associated with dysfunction in regions that compose the paralimbic system, such as the orbitofrontal cortex (OFC), insular cortex (IC), temporal pole (TP), parahippocampal gyrus (PHG) and cingulate cortex (CC). However, findings of structural alterations in these regions are inconsistent in schizophrenia, and correlations between paralimbic system measures and symptomatology and cognitive function have not been investigated.Method93 patients with schizophrenia and 99 healthy controls received structural magnetic resonance imaging and clinical and cognitive assessment. We compared gray matter volume (GMV) between the two groups using voxel-based morphometry, and evaluated correlations between abnormal GMVs and clinical variables, symptomatology and cognitive function. The assessment of cognition included measures of processing speed, verbal fluency and memory.ResultsPatients with schizophrenia demonstrated significant GMV decreases in the paralimbic system, including bilateral OFC, IC and TP (p < 0.05, FWE corrected). GMV decreases were also observed in bilateral superior temporal gyri (STG). The GMVs in bilateral OFC, left IC, left TP and bilateral STG were positively correlated with processing speed, and the GMVs in bilateral OFC were positively correlated with memory function in all participants. In our patient group, the GMV deficits were also associated with earlier age of onset, longer duration of illness, greater number of hospitalizations and more severe positive symptoms.ConclusionsGMVs in the paralimbic system were significantly reduced in schizophrenia, and these abnormalities were correlated with clinical variables, symptomatology and cognitive function. These results suggest the paralimbic system plays an important role in the pathophysiology of schizophrenia.     

A follow-up MRI study of the fusiform gyrus and middle and inferior temporal gyri in schizophrenia spectrum

While longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive gray matter reduction of the superior temporal gyrus (STG) during the early phases of schizophrenia, it remains largely unknown whether other temporal lobe structures also exhibit similar progressive changes and whether these changes, if present, are specific to schizophrenia among the spectrum disorders. In this longitudinal MRI study, the gray matter volumes of the fusiform, middle temporal, and inferior temporal gyri were measured at baseline and follow-up scans (mean inter-scan interval = 2.7 years) in 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. Both schizophrenia and schizotypal patients had a smaller fusiform gyrus than controls bilaterally at both time points, whereas no group difference was found in the middle and inferior temporal gyri. In the longitudinal comparison, the schizophrenia patients showed significant fusiform gyrus reduction (left, − 2.6%/year; right, − 2.3%/year) compared with schizotypal patients (left: − 0.4%/year; right: − 0.2%/year) and controls (left: 0.1%/year; right: 0.0%/year). However, the middle and inferior temporal gyri did not exhibit significant progressive gray matter change in all diagnostic groups. In the schizophrenia patients, a higher cumulative dose of antipsychotics during follow-up was significantly correlated with less severe gray matter reduction in the left fusiform gyrus. The annual gray matter loss of the fusiform gyrus did not correlate with that of the STG previously reported in the same subjects. Our findings suggest regional specificity of the progressive gray matter reduction in the temporal lobe structures, which might be specific to overt schizophrenia within the schizophrenia spectrum.     

Internal capsule size associated with outcome in first-episode schizophrenia

Subtle structural brain abnormalities are an established finding in first-episode psychosis. Nevertheless their relationship to the clinical course of schizophrenia is controversially discussed. In a multicentre study 45 first-episode schizophrenia patients (FE-SZ) underwent standardized MRI scanning and were followed up to 1 year. In 32 FE-SZ volumetric measurement of three regions of interests (ROIs) potentially associated with disease course, hippocampus, lateral ventricle and the anterior limb of the internal capsule (ALIC) could be performed. The subgroups of FE-SZ with good (12 patients) and poor outcome (11 patients), defined by a clinically relevant change of the PANSS score, were compared with regard to these volumetric measures. Multivariate analysis of covariance revealed a significant reduced maximal cross sectional area of the left ALIC in FE-SZ with clinically relevant deterioration compared to those with stable psychopathology. There were no differences in the other selected ROIs between the two subgroups. In conclusion, reduced maximal area of ALIC, which can be interpreted as a disturbance of fronto-thalamic connectivity, is associated with poor outcome during the 1 year course of first-episode schizophrenia.     

An MRI study of the superior temporal subregions in first-episode patients with various psychotic disorders

Morphologic abnormalities of the superior temporal gyrus (STG) have been reported in schizophrenia, but have not been extensively studied in other psychotic disorders such as affective psychosis. In the present study, magnetic resonance imaging was used to examine the volumes of the STG and its subregions [planum polare (PP), Heschl gyrus (HG), planum temporale (PT), rostral STG, and caudal STG] in 162 first-episode patients with various psychotic disorders [46 schizophrenia (31 schizophrenia and 15 schizoaffective disorder), 57 schizophreniform disorder, 34 affective psychosis, and 25 other psychoses] and 62 age- and sex-matched healthy controls. The first-episode schizophrenia patients had significantly less gray matter in HG, PT, and caudal STG bilaterally compared with all other groups, but there was no difference between the controls and affective psychosis, schizophreniform disorder, or other psychoses for any STG subregion. The STG white matter volume did not differ between groups. Our findings indicate that morphologic abnormalities of the STG gray matter are specific to schizophrenia among various psychotic disorders, implicating its role in the underlying pathophysiology of schizophrenia.     

Progressive Grey Matter Volume Changes in Patients with Schizophrenia over 6 Weeks of Antipsychotic Treatment and Their Relationship to Clinical Improvement

Cross-sectional and longitudinal studies have identified widespread and progressive grey matter volume (GMV) reductions in schizophrenia, especially in the frontal lobe. In this study, we found a progressive GMV decrease in the rostral medial frontal cortex (rMFC, including the anterior cingulate cortex) in the patient group during a 6-week follow-up of 40 patients with schizophrenia and 31 healthy controls well-matched for age, gender, and education. The higher baseline GMV in the rMFC predicted better improvement in the positive score on the Positive and Negative Syndrome Scale (PANSS), and this might be related to the improved reality-monitoring. Besides, a higher baseline GMV in the posterior rMFC predicted better remission of general symptoms, and a lesser GMV reduction in this region was correlated with better remission of negative symptoms, probably associated with ameliorated self-referential processing and social cognition. Besides, a shorter disease course and higher educational level contributed to better improvement in the general psychopathological PANSS score, and a family history was negatively associated with improvement of the negative and total PANSS scores. These phenomena might be important for understanding the neuropathological mechanisms underlying the symptoms of schizophrenia and for making clinical decisions.     

精神病未治疗期对首发未服药精神分裂症脑白质完整性的影响

目的 探讨精神病未治疗期(DUP)对首发未服药精神分裂症患者脑白质完整性的影响.方法 应用汉化的诺丁汉发病症状量表评定39例首发未服药精神分裂症患者的DUP,以其中位数为界将患者分为长DUP组和短DUP组,同时比较两组患者的性别构成、年龄、受教育年限、阳性和阴性症状量表总分.采用自旋回波序列得到弥散张量磁共振成像资料,以DTI-Studi0软件和统计参数图软件(SPM5)对所得图像进行预处理,得到的分子各向异性分数(FA)图像在SPM5软件中进行两样本t检验,获得两组FA差异统计参数图.结果 两组患者性别构成、年龄、受教育年限、阳性和阴性症状量表总分比较差异无统计学意义(P＞0.05).在P值小于0.001(未校正)水平下,长DUP组患者大脑右侧前扣带束(x=8,y=40,z=24)和左侧前额叶白质(x=32,y=34,z=4)FA值较短DUP组降低.结论 延长的DUP会降低首发未服药精神分裂症患者脑白质的完整性.     

Structural brain correlates of sensorimotor gating in antipsychotic-naive men with first-episode schizophrenia

Background: Prepulse inhibition (PPI) of the startle reflex is modulated by a complex neural network. Prepulse inhibition impairments are found at all stages of schizophrenia. Previous magnetic resonance imaging (MRI) studies suggest that brain correlates of PPI differ between patients with schizophrenia and healthy controls; however, these studies included only patients with chronic illness and medicated patients. Our aim was to examine the structural brain correlates of PPI in antipsychotic-naive patients with first-episode schizophrenia. Methods: We performed acoustic PPI assessment and structural MRI (1.5 and 3 T) in men with first-episode schizophrenia and age-matched controls. Voxel-based morphometry was used to investigate the association between PPI and grey matter volumes. Results: We included 27 patients and 38 controls in the study. Patients had lower PPI than controls. The brain areas in which PPI and grey matter volume correlated did not differ between the groups. Independent of group, PPI was significantly and positively associated with regional grey matter volume in the right superior parietal cortex. Prepulse inhibition and grey matter volume associations were also observed in the left rostral dorsal premotor cortex, the right presupplementary motor area and the anterior medial superior frontal gyrus bilaterally. Follow-up analyses suggested that the rostral dorsal premotor cortex and presupplementary motor area correlations were driven predominantly by the controls. Limitations: We used 2 different MRI scanners, which might have limited our ability to find subcortical associations since interscanner consistency is low for subcortical regions. Conclusion: The superior parietal cortex seems to be involved in the regulation of PPI in controls and antipsychotic-naive men with first-episode schizophrenia. Our observation that PPI deficits in schizophrenia may be related to the rostral dorsal premotor cortex and presupplementary motor area, brain areas involved in maintaining relevant sensory information and voluntary inhibition, warrants further study.     

首发未用药精神分裂症与精神分裂症患者健康子女静息态脑功能低频振幅研究

目的探讨首发未用药精神分裂症患者和精神分裂症患者健康子女脑功能磁共振低频振幅(amplitude of low frequency fluctuation,ALFF)的共性与差异。方法应用静息态功能磁共振ALFF的方法对年龄30岁的23例首发未用药精神分裂症患者、25名精神分裂症患者健康子女以及29名健康对照进行大脑范围内ALFF值比较。结果与对照组相比,患者组和患者子女组在左侧颞下回后部、左侧海马旁回、左侧海马、右侧中央后回、双侧楔前叶的ALFF值有统计学差异(P0.05),而患者组和患者子女组间在以上脑区的ALFF值无统计学差异(P0.05);与患者子女组和对照组相比,患者组在左侧颞下回前部、左侧颞上极、双侧距状裂周围皮层的ALFF值有统计学差异(P0.05),患者子女组和对照组间在以上脑区的ALFF值无统计学差异(P0.05)。结论首发未用药精神分裂症患者以及精神分裂症患者健康子女都存在脑功能异常;左侧颞下回后部、左侧海马旁回、左侧海马、右侧中央后回、双侧楔前叶可能是与精神分裂症遗传素质性相关的脑区;左侧颞下回前部、左侧颞上极、双侧距状裂周围皮层可能是与疾病状态性相关的脑区。     

Superior temporal gyrus in schizophrenia: a volumetric magnetic resonance imaging study

The left superior temporal gyrus (STG) has been reported to be smaller in patients with schizophrenia. The volume of the STG has been found to correlate negatively with severity of hallucinations and thought disorder. In this study, we measured the STG volume of 20 normal controls and 20 patients with schizophrenia using 3 mm contiguous coronal T1 magnetic resonance images. We found that patients had a significantly smaller left anterior STG, and that the volume of this region negatively correlated with the severity of hallucinations. The left posterior STG was not significantly smaller in patients than in controls, but its volume negatively correlated with severity of thought disorder. We also found that the left anterior STG was smaller than the right STG in patients but not in controls. The STG has at least three histologically distinct areas, each with different connections to the rest of the brain. These data are consistent with the proposition that dysfunction of the primary auditory cortex in the anterior and middle STG and auditory association cortex in the posterior STG may play a role in the production of auditory perceptual abnormalities and poor organization of thought respectively.     

Sex differences in prevalence and clinical correlates of insomnia in Chinese patients with chronic schizophrenia

Objective

It is generally recognized that there are sex differences in many aspects of schizophrenia. The main purpose of this study was to investigate the sex differences in the prevalence and clinical correlates of insomnia in patients with chronic schizophrenia.

Methods

A total of 957 patients who met the DSM-IV diagnostic criteria for schizophrenia were recruited in this cross-sectional study (male/female = 630/327). Demographic, clinical, and insomnia data were collected using self-reported questionnaires. Fasting blood samples were collected to evaluate the status of blood lipids. Psychopathological symptoms were evaluated using the Positive and Negative Syndrome Scale (PANSS).

Results

The prevalence rate of insomnia in female patients with schizophrenia was significantly higher than that in male patients (17.3% for males and 26.3% for females; χ² = 10.74, p = 0.001). Regression analysis showed that in male patients, insomnia was independently associated with severe PANSS positive symptoms, severe PANSS depressive factor, and high levels of low-density lipoprotein levels, while in female patients, insomnia was associated with low education level, high PANSS depressive factor, and high levels of apolipoprotein B levels.

Conclusion

This study illustrates that insomnia is more frequent in female than male schizophrenia patients, and that there are differences in the clinical correlates of insomnia by sex, suggesting that sex differences should be considered in prevention and treatment strategies for coexisting insomnia in schizophrenia patients.

     

吸烟对精神分裂症男性患者精神病理症状的影响

目的 分析吸烟对精神分裂症临床精神病理症状的影响,探索精神分裂症患者高比例吸烟的原因.方法 收集慢性精神分裂症吸烟患者(332例)和非吸烟患者(95例)共427例,首次发病(以下简称首发)精神分裂症吸烟患者(22例)和非吸烟患者(41例)共63例,均为男性;使用阳性和阴性症状最表(PANSS)评定其临床精神病理症状.结果 (1)在慢性精神分裂症患者巾,吸烟组PANSS阴性症状分量表中的情感交流障碍得分[(3.9±1.5)分]、被动或淡漠得分[(3.6±1.6)分]及其总分[(24.0.±8.2)分]低于非吸烟组[分别为(4.4.±1.7)分、(4.0±1.7)分和(26.3.±9.5)分;P<0.05];PANSS阴性症状分量表7个条目得分及其总分、一般精神病理分量表总分和PANSS总分与患者每天的吸烟量呈负相关(P<0.05～0.01);阴性症状分量表中的情感交流障碍[比值比(OR)=0.832,95%可信区间(95%CI)=0.691～0.980,P=0.029]和一般精神病理分量表中的紧张(OR=0.534,95%CI=0.363～0.786,P=0.001)进入Logistic模型.(2)在首发精神分裂症患者中,吸烟组在阴性症状分量表中的情绪退缩得分[(2.7±1.3)分]、被动或淡漠得分[(2.7 ±1.3)分]低于非吸烟组[分别为(3.5±1.3)分和(3.5±1.4)分;P<0.05];一般精神病理分量表中的动作迟缓与患者每天的吸烟量呈负相关,自知力缺乏与吸烟量呈正相关(均P<0.05);PANSS一般精神病理分量表中的动作迟缓(OR=0.589,95%CI:0.350～0.989,P=0.045)进入Logistic模型.结论 吸烟对阴性症状的正性作用可能是精神分裂症患者高比例吸烟的原因之一.     

Serum brain-derived neurotrophic factors in Taiwanese patients with drug-naïve first-episode schizophrenia: Effects of antipsychotics

Objectives: Brain-derived neurotrophic factors (BDNF) are known to be related to the psychopathology of schizophrenia. However, studies focussing on drug-naïve first-episode schizophrenia are still rare.

Methods: Over a 5-year period, we investigated the serum BDNF levels in patients with first-episode drug-naïve schizophrenia and compared them to age- and sex-matched healthy controls. We also explored the association between antipsychotic doses, positive and negative syndrome scale (PANSS) scores, and serum BDNF levels before and after a 4-week antipsychotic treatment.

Results: The baseline serum BDNF levels of 34 patients were significantly lower than those of the controls (df?=?66, P?=?.001). Although the PANSS scores of 20 followed-up patients improved significantly after antipsychotic treatment, the elevation of the serum BDNF levels was not statistically significant (P?=?.386). In addition, Pearson’s correlation test showed significant correlations between pre-treatment negative scale scores and percentage changes in BDNF (P?=?.002).

Conclusions: The peripheral BDNF levels in Taiwanese patients with drug-naïve first-episode schizophrenia, compared with healthy controls, did not elevate after antipsychotic treatment, and pre-treatment negative symptoms played a pivotal role in trajectories of serum BDNF levels. Large samples will be needed in future studies to verify these results.     

Structural brain correlates of sensorimotor gating in antipsychotic-naive men with first-episode schizophrenia

Background

Prepulse inhibition (PPI) of the startle reflex is modulated by a complex neural network. Prepulse inhibition impairments are found at all stages of schizophrenia. Previous magnetic resonance imaging (MRI) studies suggest that brain correlates of PPI differ between patients with schizophrenia and healthy controls; however, these studies included only patients with chronic illness and medicated patients. Our aim was to examine the structural brain correlates of PPI in antipsychotic-naive patients with first-episode schizophrenia.

Methods

We performed acoustic PPI assessment and structural MRI (1.5 and 3 T) in men with first-episode schizophrenia and age-matched controls. Voxel-based morphometry was used to investigate the association between PPI and grey matter volumes.

Results

We included 27 patients and 38 controls in the study. Patients had lower PPI than controls. The brain areas in which PPI and grey matter volume correlated did not differ between the groups. Independent of group, PPI was significantly and positively associated with regional grey matter volume in the right superior parietal cortex. Prepulse inhibition and grey matter volume associations were also observed in the left rostral dorsal premotor cortex, the right presupplementary motor area and the anterior medial superior frontal gyrus bilaterally. Follow-up analyses suggested that the rostral dorsal premotor cortex and presupplementary motor area correlations were driven predominantly by the controls.

Limitations

We used 2 different MRI scanners, which might have limited our ability to find subcortical associations since interscanner consistency is low for subcortical regions.

Conclusion

The superior parietal cortex seems to be involved in the regulation of PPI in controls and antipsychotic-naive men with first-episode schizophrenia. Our observation that PPI deficits in schizophrenia may be related to the rostral dorsal premotor cortex and presupplementary motor area, brain areas involved in maintaining relevant sensory information and voluntary inhibition, warrants further study.     

Lateral ventricle differences between first-episode schizophrenia and first-episode psychotic bipolar disorder: A population-based morphometric MRI study

Abstract

Objectives. The extent to which psychotic disorders fall into distinct diagnostic categories or can be regarded as lying on a single continuum is controversial. We compared lateral ventricle volumes between a large sample of patients with first-episode schizophrenia or bipolar disorder and a healthy control group from the same neighbourhood. Methods. Population-based MRI study with 88 first-episode psychosis (FEP) patients, grouped into those with schizophrenia/schizophreniform disorder (N=62), bipolar disorder (N=26) and 94 controls. Results. Right and left lateral ventricular and right temporal horn volumes were larger in FEP subjects than controls. Within the FEP sample, post-hoc tests revealed larger left lateral ventricles and larger right and left temporal horns in schizophrenia subjects relative to controls, while there was no difference between patients with bipolar disorder and controls. None of the findings was attributable to effects of antipsychotics. Conclusions. This large-sample population-based MRI study showed that neuroanatomical abnormalities in subjects with schizophrenia relative to controls from the same neighbourhood are evident at the first episode of illness, but are not detectable in bipolar disorder patients. These data are consistent with a model of psychosis in which early brain insults of neurodevelopmental origin are more relevant to schizophrenia than to bipolar disorder.     

Decreased density of muscarinic receptors in the superior temporal gyrusin schizophrenia

Recent studies have indicated that muscarinic receptors are involved in the pathophysiology in schizophrenia, particularly in cognitive deficits. The superior temporal gyrus (STG) is an area that has also been strongly implicated in the pathophysiology of schizophrenia. Therefore, in this study, we investigated the binding density of two muscarinic antagonists, [(3)H]pirenzepine and [(3)H]AF-DX 384, in the STG of schizophrenia patients compared with controls. A significant decrease (44% in the superficial layers and 48% in the deep layers, P<0.01) in binding density of [(3)H]pirenzepine was observed in schizophrenia patients, which suggested a reduction of muscarinic M1 and M4 receptor densities in the STG of schizophrenia patients. A tendency toward decreased [(3)H]AF-DX 384 binding density (34%, P=0.09) was also observed in schizophrenia patients compared with controls. Because of the positive correlation between [(3)H]pirenzepine and [(3)H]AF-DX 384 binding, and, insofar as both ligands have high affinities for the M4 receptor, the involvement of M4 receptor alteration is also suggested in the STG in schizophrenia. These results suggest that changes of the muscarinic receptors M1 and M4 might contribute to the STG pathology in schizophrenia.     

基于形变的形态学测量对首次发病未服药抑郁症患者大脑灰质异常的研究

目的:探讨首次发病未服药抑郁症患者（major depressive disorder）大脑灰质结构改变以及抑郁症早期诊断的影像学指标。方法:对38例抑郁症患者（抑郁症组）和65名年龄、性别相匹配的健康对照（对照组）进行3D T 1加权结构像磁共振成像扫描,采用基于形变的形态学测量（deformation-...