Multimodal morphometry and functional magnetic resonance imaging in schizophrenia and auditory hallucinations

AIM:To validate a multimodal[structural and functional magnetic resonance(MR)]approach as coincidence brain clusters are hypothesized to correlate with clinical severity of auditory hallucinations.METHODS:Twenty-two patients meeting Diagnostic and Statistical Manual of Mental Disorders(fourth edition,DSM-Ⅳ)criteria for schizophrenia and experiencing persistent hallucinations together with 28 healthy controls were evaluated with structural and functional MR imaging with an auditory paradigm designed to replicate those emotions related to the patients’hallucinatory experiences.Coincidence maps were obtained by combining structural maps of gray matter reduction with emotional functional increased activation.Abnormal areas were correlated with the brief psychiatric rating scale(BPRS)and the psychotic symptom rating scale(PSYRATS)scales.RESULTS:The coincidence analysis showed areas with coexistence gray matter reductions and emotional activation in bilateral middle temporal and superior temporal gyri.Significant negative correlations between BPRS and PSYRATS scales were observed.BPRS scores were negatively correlated in the middle temporal gyrus(right)(t=6.86,P=0.001),while negative PSYRATS correlation affected regions in both the superior temporal gyrus(left)(t=7.85,P=0.001)and middle temporal gyrus(left)(t=4.97,P=0.002).CONCLUSION:Our data identify left superior and middle temporal gyri as relevant areas for the understanding of auditory hallucinations in schizophrenia.The use of multimodal approaches,sharing structural and functional information,may demonstrate areas specifically linked to the severity of auditory hallucinations.     

Evaluation of regional cerebral blood flow in fahr disease with schizophrenia-like psychosis: a case report

We report the case of a patient with Fahr disease presenting with schizophrenia-like psychosis for whom a technetium Tc99 methyl cysteinate dimmer brain study was used to evaluate regional blood flow. A brain single photon-emission CT study showed increased cerebral blood flow to the bilateral temporal lobes. Such perfusion abnormalities may reflect psychotic symptoms, including auditory hallucinations and delusions, which suggests a disruption of the cortico-subcortical neural circuits in psychosis.     

Chronic auditory hallucinations in schizophrenic patients: MR analysis of the coincidence between functional and morphologic abnormalities

PURPOSE: To prospectively evaluate if functional magnetic resonance (MR) imaging abnormalities associated with auditory emotional stimuli coexist with focal brain reductions in schizophrenic patients with chronic auditory hallucinations. MATERIALS AND METHODS: Institutional review board approval was obtained and all participants gave written informed consent. Twenty-one right-handed male patients with schizophrenia and persistent hallucinations (started to hear hallucinations at a mean age of 23 years +/- 10, with 15 years +/- 8 of mean illness duration) and 10 healthy paired participants (same ethnic group [white], age, and education level [secondary school]) were studied. Functional echo-planar T2*-weighted (after both emotional and neutral auditory stimulation) and morphometric three-dimensional gradient-recalled echo T1-weighted MR images were analyzed using Statistical Parametric Mapping (SPM2) software. Brain activation images were extracted by subtracting those with emotional from nonemotional words. Anatomic differences were explored by optimized voxel-based morphometry. The functional and morphometric MR images were overlaid to depict voxels statistically reported by both techniques. A coincidence map was generated by multiplying the emotional subtracted functional MR and volume decrement morphometric maps. Statistical analysis used the general linear model, Student t tests, random effects analyses, and analysis of covariance with a correction for multiple comparisons following the false discovery rate method. RESULTS: Large coinciding brain clusters (P < .005) were found in the left and right middle temporal and superior temporal gyri. Smaller coinciding clusters were found in the left posterior and right anterior cingular gyri, left inferior frontal gyrus, and middle occipital gyrus. CONCLUSION: The middle and superior temporal and the cingular gyri are closely related to the abnormal neural network involved in the auditory emotional dysfunction seen in schizophrenic patients.     

基于体素的形态测量学在震颤麻痹型多系统萎缩中的应用

目的 评价震颤麻痹型多系统萎缩(MSA-P型)患者全脑灰、白质体积减少区域及分布特征.方法 选取13例临床拟诊为MSA-P型可能性大的患者及14名年龄匹配的正常对照者行全脑三维快速扰相梯度回波(3D fast spoiled gradient echo,3D-FSPGR)序列扫描,采用基于体素的形态测量学(voxel-based morphometry,VBM)分析方法的统计参数图软件(statistical parametric mapping,SPM)8,对MSA-P型患者及正常对照者的灰、白质体素进行分析.结果 与正常对照者相比,MSA-P患者的脑灰、白质体积均减少;脑灰质减少区多数区域呈双侧对称分布:包括双侧辅助运动区、背侧后扣带皮层、额叶内侧回、颞上回、小脑半球皮层等;少数区域仅累及单侧,如右侧初级运动皮层、体感联合皮层及左侧下前扣带皮层等.脑白质区主要累及双侧额上回、楔前叶、额叶下,左侧颞上回、扣带回及右侧额眶回、颞叶下等.结论 VBM方法具有自动、全面的特点,能客观地反映MSA-P患者组全脑结构的差异.     

帕金森病认知障碍患者脑结构的体素形态学研究

目的：分析帕金森病(PD)患者脑灰质异常区域及分布特征,探寻与轻度认知障碍(MCI)有关的脑结构变化。方法采用基于体素的形态学测量(VBM)方法,对20例伴 PD-MCI 患者、17例无轻度认知障碍 PD(PD-nMCI)患者及20例正常对照组(NC)的3组3D-T1 WI 脑容积数据进行处理统计,得到3组全脑灰质图像。结果与 NC 组相比,PD-nMCI 组脑灰质体积异常减少的脑区包括：右侧梭状回、右颞中下回、右钩回及左侧颞上回。与 PD-nMCI 组相比,PD-MCI 组脑灰质体积异常减少的脑区包括：两侧额叶(两额中下回、左侧中央前回)、颞叶(右颞中回、左颞上回)、岛叶、右枕叶(右楔叶、舌回)、右后扣带回。结论PD-nMCI 患者灰质体积的缺失相对局限,随认知障碍的出现、发展,缺失脑区的范围逐渐扩大,其中两侧额叶中下回、左侧中央前回的体积缺失与 PD 患者的 MCI 关系密切。     

VBM-DARTEL法观察带状疱疹后遗神经痛患者脑灰质体积的形态学改变

目的 观察带状疱疹后遗神经痛(PHN)患者全脑灰质形态学改变,探讨其形态学改变与PHN患者视觉模拟评分(VAS)及病程之间的相关性.方法 对17例PHN患者及17例正常对照的3D T1WI结构图像进行预处理,采用VBM-DARTEL法比较2组分割后的脑灰质体积,并分析脑灰质体积改变与PH患者VAS及病程之间的相关性.结果 相对于正常对照组,PHN患者脑灰质体积减小的脑区包括:双侧眶额区(眶回及直回)、左侧额下回、左侧岛叶、左侧尾状核、右侧扣带回、左侧颞上回、左侧楔叶、双侧小脑前后叶;PHN患者脑灰质体积增加的脑区包括:双侧额上回、左侧额中回、小脑蚓部、脑桥;PHN组两侧半球脑灰质体积改变不对称(左侧>右侧);PHN患者脑灰质体积异常脑区与VAS及病程之间均无相关性.结论 VBM-DARTEL法揭示PHN患者存在广泛脑灰质体积异常,这些改变可能在疼痛的形成及慢性状态维持中发挥重要作用.     

Increased accumulation of N-isopropyl-(I-123) p-iodoamphetamine in the left auditory area in a schizophrenic patient with auditory hallucinations

A schizophrenic patient with auditory hallucinations is reported in which IMP markedly accumulated in the left superior temporal and inferior parietal lobes which correspond to the left primary and secondary cortical auditory areas and angular gyrus, respectively.     

Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

Objective

To investigate gray matter concentration changes in the brains of narcoleptic patients.

Materials and Methods

Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images.

Results

Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05).

Conclusion

Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy.     

遗忘型轻度认知损害的全脑灰质基于体素的MRI形态分析

目的：利用优化基于体素的MRI形态分析（voxel-based morphometry,VBM）,研究遗忘型轻度认知损害（amnestic mild cognitive impairment,aMCI）和正常老年人的脑灰质体积变化。方法：选取aMCl患者20例和正常老年对照18例,MRI排除脑内其他病变,然后行高分辨率三维T1WI扫描。应用优化VBM方法处理数据,将脑组织分割成灰质、白质和脑脊液,最后应用两样本t检验比较两组被试灰质体积改变。结果：VBM结果显示与正常老年对照组比较,aMCI患者组双侧额颞叶出现广泛的灰质体积减少,具体脑区为右侧海马钩回、双侧额下回、双侧额中回、右侧额上回、双颞叶额中回、左侧颞下回、左侧颞上回、右侧顶上小叶、左侧枕中回等结构灰质体积小于对照组,差异有统计学意义（P〈0.001）。结论：VBM方法可显示aMCl患者全脑灰质萎缩情况,对临床早期诊断aMCl患者有重要价值,具有广阔的临床应用前景。     

蒙汉双语者与单汉语者语义加工差异脑机制的功能磁共振成像研究

目的 通过熟练蒙汉双语者及单汉语志愿者的语言功能磁共振成像,探讨蒙汉双语者及汉语志愿者在汉语语义判断过程中汉语信息加工差异的脑机制.方法 采用汉语词的语义判断任务,15名蒙汉双语健康志愿者（男8名,女7名）和15名汉语健康志愿者（男7名,女8名）进行功能磁共振成像研究.应用软件包AFNI分析两种语言任务的脑功能激活情况及其差异.结果 熟练蒙汉双语者及单汉语志愿者在汉语语义信息加工过程中,均激活语义信息加工的经典脑区,包括左侧颞中回后部、左侧顶下小叶、左侧额下回三角部、双侧辅助运动区等区域.比较蒙汉双语者与汉语者在加工汉语的语义信息过程的差异,发现蒙汉双语者主要在双侧枕叶、扣带回后部、左侧颞上回和颞中回后部的激活显著比单汉语者的增加,而在双侧基底节、右侧舌回、左侧额下回眶部,表现比单汉语者的激活更弱.结论 蒙汉双语者加工第二语言存在特殊性,功能磁共振成像研究能够为双语者的语言加工脑机制提供影像学依据.     

MR imaging of the human brain at 1.5 T: regional variations in transverse relaxation rates in the cerebral cortex.

BACKGROUND AND PURPOSE: Heterogeneity in cortical signal intensity on T2-weighted MR images has been recently documented. Using a whole-brain, multiecho MR imaging technique, we sought to determine the T2 relaxation times of nine predefined regions in the cerebral cortex and one region in the deep gray matter. METHODS: Ten adult volunteers (nine men and one woman; age range, 18-40 y; average age, 30.8 y) underwent whole-brain imaging with an oblique coronal multiecho 3D Carr-Purcell-Meiboom-Gill MR sequence at 1000/25, 50, 75, 100, 125, and 150 (TR/TE). T2 measurements were obtained, with variably sized regions of interest, from the primary auditory cortex, primary visual cortex, caudate nucleus, superior frontal gyrus, inferior temporal gyrus, middle temporal gyrus, superior temporal gyrus, insula cortex, cingulate gyrus, and hippocampus. Repeated-measures analysis of variance was used to assess the existence of differences in T2 measurements among the anatomic locations. RESULTS: On the basis of T2 measurements, the gray matter structures examined could be divided into four statistically different groups. In ascending order of T2 measurements, the first group consisted of the primary auditory cortex and primary visual cortex; the second group, the caudate nucleus, superior frontal gyrus, inferior temporal gyrus, middle temporal gyrus, and superior temporal gyrus; the third group, the insula cortex; and the fourth group, the cingulate gyrus and hippocampus. CONCLUSION: Significant variation in T2 values among the cortical gray matter of the human brain exists.     

The influence of gender on auditory and language cortical activation patterns: preliminary data

PURPOSE AND BACKGROUND: Intersex cortical and functional asymmetry is an ongoing topic of investigation. In this pilot study, we sought to determine the influence of acoustic scanner noise and sex on auditory and language cortical activation patterns of the dominant hemisphere. MATERIALS AND METHODS: Echoplanar functional MR imaging (fMRI; 1.5T) was performed on 12 healthy right-handed subjects (6 men and 6 women). Passive text listening tasks were employed in 2 different background acoustic scanner noise conditions (12 sections/2 seconds TR [6 Hz] and 4 sections/2 seconds TR [2 Hz]), with the first 4 sections in identical locations in the left hemisphere. Cross-correlation analysis was used to construct activation maps in subregions of auditory and language relevant cortex of the dominant (left) hemisphere, and activation areas were calculated by using coefficient thresholds of 0.5, 0.6, and 0.7. RESULTS: Text listening caused robust activation in anatomically defined auditory cortex, and weaker activation in language relevant cortex of all 12 individuals. As a whole, there was no significant difference in regional cortical activation between the 2 background acoustic scanner noise conditions. When sex was considered, men showed a significantly (P < .01) greater change in left hemisphere activation during the high scanner noise rate condition than did women. This effect was significant (P < .05) in the left superior temporal gyrus, the posterior aspect of the left middle temporal gyrus and superior temporal sulcus, and the left inferior frontal gyrus. CONCLUSION: Increase in the rate of background acoustic scanner noise caused increased activation in auditory and language relevant cortex of the dominant hemisphere in men compared with women where no such change in activation was observed. Our preliminary data suggest possible methodologic confounds of fMRI research and calls for larger investigations to substantiate our findings and further characterize sex-based influences on hemispheric activation patterns.     

Differences in brain structure in deaf persons on MR imaging studied with voxel-based morphometry

BACKGROUND AND PURPOSE: The loss of a major sensory input early in life is known to cause alterations in neuronal connectivity and physiology at the cellular level, but effects on gross anatomy are less well understood. The purpose of this study was to compare volumetric structural brain MR imaging scans of deaf versus hearing subjects by using voxel-based morphometry (VBM). The hypothesis was that the deaf would have relative hypoplasia in the temporal lobe centers involved in hearing and speech. METHODS: T1-weighted volumetric images from 53 prelingually deaf persons and 51 control subjects were analyzed with VBM. Initial segmentations were spatially normalized, and then these deformation parameters were applied to the original images, which were again segmented. Statistic parametric mapping was then applied on a voxel-by-voxel basis to determine group differences and asymmetries. RESULTS: The white matter analysis revealed a statistically significant focal deficit in the deaf persons in the left posterior superior temporal gyrus (STG), corresponding to white matter inferior to auditory cortex. Gray matter asymmetries in the deaf persons were overall similar to that in hearing persons but a focal loss of asymmetry was noted in the posterior STG white matter in the deaf persons. CONCLUSION: These results support the hypothesis that there are gross alterations in brain anatomy as a consequence of early deafness. The white matter deficit in the posterior left superior temporal gyrus may represent hypoplasia of the auditory/speech related tracts. Hemispheric asymmetries however remain largely intact.     

Activation of auditory white matter tracts as revealed by functional magnetic resonance imaging

Introduction

The ability of functional magnetic resonance imaging (fMRI) to detect activation in brain white matter (WM) is controversial. In particular, studies on the functional activation of WM tracts in the central auditory system are scarce. We utilized fMRI to assess and characterize the entire auditory WM pathway under robust experimental conditions involving the acquisition of a large number of functional volumes, the application of broadband auditory stimuli of high intensity, and the use of sparse temporal sampling to avoid scanner noise effects and increase signal-to-noise ratio.

Methods

Nineteen healthy volunteers were subjected to broadband white noise in a block paradigm; each run had four sound-on/off alternations and was repeated nine times for each subject. Sparse sampling (TR?=?8 s) was used.

Results

In addition to traditional gray matter (GM) auditory center activation, WM activation was detected in the isthmus and midbody of the corpus callosum (CC), tapetum, auditory radiation, lateral lemniscus, and decussation of the superior cerebellar peduncles. At the individual level, 13 of 19 subjects (68 %) had CC activation. Callosal WM exhibited a temporal delay of approximately 8 s in response to the stimulation compared with GM.

Conclusions

These findings suggest that direct evaluation of the entire functional network of the central auditory system may be possible using fMRI, which may aid in understanding the neurophysiological basis of the central auditory system and in developing treatment strategies for various central auditory disorders.     

Improvement of auditory hallucinations and reduction of primary auditory area's activation following TMS

Background

In the present case study, improvement of auditory hallucinations following transcranial magnetic stimulation (TMS) therapy was investigated with respect to activation changes of the auditory cortices.

Methods

Using functional magnetic resonance imaging (fMRI), activation of the auditory cortices was assessed prior to and after a 4-week TMS series of the left superior temporal gyrus in a schizophrenic patient with medication-resistant auditory hallucinations.

Results

Hallucinations decreased slightly after the third and profoundly after the fourth week of TMS. Activation in the primary auditory area decreased, whereas activation in the operculum and insula remained stable.

Conclusions

Combination of TMS and repetitive fMRI is promising to elucidate the physiological changes induced by TMS.     

轻度Alzheimer患者与正常老年人全脑灰质基于体素的形态学比较

目的 利用基于体素的形态学研究方法比较轻度Alzheimer病（AD）患者和正常老年人全脑灰质的差别。方法 对16例正常志愿者和13例轻度AD患者进行了三维T1WI扫描，数据在参数统计软件包SPM99下进行头颅标准化、分割、平滑的后处理后，对AD组和对照组的全脑灰质进行基于体素的统计学比较。结果 AD组的双侧海马及杏仁核、双侧岛叶、双侧内侧丘脑、双侧直回、右侧颞上回、右侧尾状核、右侧前额叶、右侧前脑基底部和有侧部分枕叶与对照组的灰质密度差异具有统计学意义（P〈0．001），这些区域的体素数目从36个至282个不等。结论 基于体素的形念学研究能够发现AD患者中广泛的大脑灰质的萎缩，从而更加全面地评价AD患者的脑结构改变。     

Radiation-induced changes in normal-appearing gray matter in patients with nasopharyngeal carcinoma: a magnetic resonance imaging voxel-based morphometry study

Introduction

Evidence is accumulating that temporal lobe radiation necrosis in patients with nasopharyngeal carcinoma (NPC) after radiotherapy (RT) could involve gray matter (GM). The purpose of the study was to assess the radiation-induced GM volume differences between NPC patients who had and had not received RT and the effect of time after RT on GM volume differences in those patients who had received RT.

Methods

We used magnetic resonance imaging voxel-based morphometry (VBM) to assess differences in GM volume between 30 NPC patients with normal-appearing whole-brain GM after RT and 15 control patients with newly diagnosed but not yet medically treated NPC. Correlation analyses were used to investigate the relationship between GM volume changes and time after RT.

Results

Patients who had received RT had GM volume decreases in the bilateral superior temporal gyrus, left middle temporal gyrus, right fusiform gyrus, right precentral gyrus, and right inferior parietal lobule (p?<?0.001, uncorrected, cluster size >100 voxels). Moreover, the correlation analysis indicated that regional GM volume loss in the left superior temporal gyrus, left middle temporal gyrus, and right fusiform gyrus were negatively related to the mean dose to the ipsilateral temporal lobe, respectively.

Conclusion

These results indicate that GM volume deficits in bilateral temporal lobes in patients who had received RT might be radiation-induced. Our findings might provide new insight into the pathogenesis of radiation-induced structural damage in normal-appearing brain tissue. Yet this is an exploratory study, whose findings should therefore be taken with caution.     

精神分裂症患者脑结构及功能的多模态影像Meta分析

目的 研究在未用药物干扰前提下精神分裂症患者的脑结构及功能变化及两者之间的关系.方法 系统地从PubMed、Embase、Web of Science和The Cochrane Library数据库上检索相应文献.多模态分析方法采用软件"Seed-based d Mapping".结果 纳入14篇结构研究,包括446例患者和461例正常对照.纳入的15篇功能MRI及PET研究中,共有360例患者和396例正常对照.多模态结果分析表明结构和功能大部分重叠的脑区在额颞叶,双侧扣带回/扣带旁回,双侧岛叶,基底节及左侧小脑.结论 排除药物干扰后发现精神分裂症患者结构和功能重叠的脑区大部分在默认网络(DMN)和听觉网络(AN).在这2种网络中,结构和功能变化的方向不一致,可能反映了精神分裂症患者大脑不同的病理生理改变.     

Abnormal brain function in neuromyelitis optica: A fMRI investigation of mPASAT

PurposeCognitive impairment with the Neuromyelitis Optica (NMO) patients is debated. The present study is to study patterns of brain activation in NMO patients during a pair of task-related fMRI.Materials and methodsWe studied 20 patients with NMO and 20 control subjects matched for age, gender, education and handedness. All patients with NMO met the 2006 Wingerchuk diagnostic criteria. The fMRI paradigm included an auditory attention monitoring task and a modified version of the Paced Auditory Serial Addition Task (mPASAT). Both tasks were temporally and spatially balanced, with the exception of task difficulty.ResultsIn mPASAT, Activation regions in control subjects included bilateral superior temporal gyri (BA22), left inferior frontal gyrus (BA45), bilateral inferior parietal lobule (BA7), left cingulate gyrus (BA32), left insula (BA13), and cerebellum. Activation regions in NMO patients included bilateral superior temporal gyri (BA22), left inferior frontal gyrus (BA9), right cingulate gyrus (BA32), right inferior parietal gyrus (BA40), left insula (BA13) and cerebellum. Some dispersed cognition related regions are greater in the patients.ConclusionsThe present study showed altered cerebral activation during mPASAT in patients with NMO relative to healthy controls. These results are speculated to provide further evidence for brain plasticity in patients with NMO.     

低级别胶质瘤术前语言功能区的fMRI研究

目的：采用恻研究低级胶质瘤语言功能区分布及偏侧性特点。方法：对15例左侧额、颞叶经病理证实的低级别胶质瘤（WHOI～Ⅱ级）患者进行例术前图片命名刺激任务的删研究,另选择10例健康人作为对照组。哪数据处理采用工作站自带软件显示激活脑区并计算偏侧性指数（LI）。结果：对照组激活脑区：左侧为主的双侧额下回、额中回、左侧颞上回、以左侧为主的双侧顶上小叶、前运动区、双侧枕叶、双侧小脑。胶质瘤组的激活脑区：双侧额下回、额中回、左侧为主的双侧颞上回、双侧顶上小叶、双侧枕叶、双侧小脑等。对照组中8例表现为左侧大脑半球优势,2例为双侧大脑半球优势,LI值为84．61％。患者组中5例表现为左侧大脑半球优势,3例为右侧大脑半球优势,7例表现为双侧大脑半球优势,LI为60．15％。结论：fMRI能在术前可靠显示低级别胶质瘤周围语言功能区的分布及语言偏侧性,对术前计划制定有重要意义。