抑郁症患者情绪图片刺激早期低频脑磁图研究

目的：探讨抑郁症患者给予视觉情绪图片刺激早期0～100ms、100～200ms、200～300ms3个时段8～30Hz的神经磁场激活特征。方法：8例抑郁症患者及12例健康右利手对照者,在给予国际情绪图片库（IAPS）正性、中性、负性情绪图片刺激同时记录脑磁图信号,使用SPM8b软件进行数据分析：设两样本t检验P〈0.01（未校正）和K值≥10个体素范围为差异有统计学意义。结果：与对照组相比,抑郁组在正性情绪图片刺激下,100～200ms内的左侧额下回,右侧的终板旁回、额内侧回、海马回激活增强。在中性情绪图片刺激下,抑郁组在0～100ms的右侧豆状核、岛叶、额上回,左内侧额叶,100～200ms内的右侧岛叶、豆状核壳核及屏状核,左侧额下回、额上回、颞上回,200～300ms内的右侧岛叶、豆状核、尾状核体激活增强。负性情绪图片刺激下抑郁组在0～100ms内的右侧颞上回、岛叶、尾状核头部、额中下回激活增强,100～200ms内的右侧额中回、尾状核体,200～300ms内右额下回激活增强。此外还比较一致的发现抑郁组在楔前叶、后扣带回等顶叶脑区激活降低。结论：抑郁个体起注意调节功能的顶叶脑区如楔前叶功能不足,对视觉皮质向前部脑区情绪信息颞叶底部传递通路抑制不足,腹侧前额皮质、岛叶过度的激活,可能是抑郁症的一个发病基础。     

抑郁症首次发作患者情绪偏向任务的脑功能磁共振成像研究

目的 研究抑郁症首次发作(以下简称首发)患者对不同性质情绪线索的差异脑激活反应,以探讨抑郁症患者"负性情绪偏向性"的脑活动特征.方法 14例抑郁症首发患者与14名配对健康对照者,接受国际情绪图片系统中正性-中性-负性三组图片刺激的脑功能磁共振成像(fMRI)扫描,任务为组块设计;以文拉法辛(75～150 mg/d,口服)治疗患者,随访12周;以汉密尔顿抑郁量表(HAMD17)减分率评估疗效;用神经功能影像分析(AFNI)软件处理影像数据.结果 (1)文拉法辛治疗8周时有效率为58%;12周时有效率为92%,HAMD17总分减分率为60%.(2)两组均激活的脑区包括双侧额中回、双侧背外侧前额叶皮质、左侧丘脑、双侧岛叶、双侧颞叶、双侧杏仁核和海马.(3)在正性/中性图片激活的脑区中,患者组双侧额中回(右侧0.11%,左侧0.09%)及左侧丘脑(0.31%)激活强度均低于对照组(分别为0.98%,1.17%和1.32%;P＜0.05);左侧岛叶(1.03%)及双侧杏仁核(右侧0.47%,左侧0.11%)的激活强度高于对照组(分别为0.45%,-0.34%和-0.49%;P＜0.05).对于负性图片,患者组左侧额中回(2.77%)、左背外侧前额叶皮质(0.18%)、左侧岛叶(1.36%)、左侧颞叶(0.33%)和右侧杏仁核(0.44%)的激活强度高于对照组(分别为1.91%.-0.32%.0.91%,-0.31%,-0.29%;P＜0.05);患者组左侧丘脑激活强度(-0.79%)低于对照组(1.15%;P＜0.05).(4)治疗后,对于正性图片,患者组左侧、右侧额中回及左侧丘脑激活增加为1.21%,1.14%及1.23%(P＜0.05).对于负性图片,左侧额中回(2.05%)、左外侧前额叶皮质(-0.42%)及左侧岛叶(0.73%)的激活降低(P＜0.05);左侧丘脑(1.53%)激活增加(P＜0.05).结论 前额叶、左侧岛叶、左侧颞叶、杏仁核和左侧丘脑对不同性质情绪诱导线索的异常激活,与抑郁症首发患者偏向性情绪障碍相关;文拉法辛对前额叶、左侧岛叶和丘脑的异常激活有调节作用.     

图片命名处理过程中的脑电变化及其空间溯源定位

目的探讨高密度脑电图及其溯源定位技术研究视觉语言处理加工过程,构建视觉语言处理的时空间网络,阐述大脑对图片信息的动态处理。方法本研究入组30例正常志愿受试者,均完成靶刺激和背景刺激记录。剔除数据记录不佳者,实际数据分析23例,分为靶刺激组和背景刺激组,每组均为23例。使用无创256导联高密度脑电图监测图片命名任务,分析事件相关电位和γ波小波,利用任务脑电信息与背景刺激有显著相关时间段的脑电数据进行溯源定位分析。结果事件相关电位分析:图片命名任务处理过程早期在100 ms和170 ms处出现峰值电位,295ms和550～640 ms时段脑电数据目标刺激与背景刺激时段比较,差异有统计学意义(P0.05)。脑电γ波小波分析显示波段35～45 Hz、时段350～400 ms处差异有统计学意义(P0.05)。时间段溯源定位研究提示:在100 ms、170 ms、295ms、350～400 ms和550～640 ms时段,分别发现双侧顶下小叶参与视觉信息的整合过程、双侧前颞叶参与概念的提取过程,左侧前颞叶和左侧顶下小叶协同对词意表征进行处理、左侧缘上回与岛盖部进行了语音编码、Broca区与运动皮质协同处理发音过程。结论高密度脑电图及溯源定位技术可以从语言处理过程的时间维度和定位空间维度构建视觉-语言通路在不同脑区之间的动态联系过程。     

草酸艾司西酞普兰对抑郁症患者事件相关电位P300的影响

目的:探讨草酸艾司西酞普兰对抑郁症患者的事件相关电位P300影响。方法:随机将年龄在18～65岁之间符合中国精神障碍分类与诊断标准第3版抑郁症诊断标准患者30例作为研究组,选择30例性别年龄健康者作为对照组。研究组予草酸艾司西酞普兰治疗。两组分别予听觉P300检测,比较P300潜伏期及波幅的差异。结果:研究组Fz、Pz点潜伏期分别为(319±23)ms、(315±20)ms均比对照组分别为(300±22)ms、(299±21)ms延长,研究组Fz、Cz、Pz点分别为(2.5±1.8)μV、(2.6±2.4)μV、(2.5±3.3)μV波幅均比对照组分别为(3.8±2.0)μV、(3.7±1.9)μV、(4.1±3.0)μV降低(P<0.05或P<0.01)。治疗8周后,研究组Fz、Pz点潜伏期分别为(301±19)ms、(305±19)ms]明显缩短,Fz、Cz、Pz点分别为(3.5±1.8)μV、(3.7±2.1)μV、(3.6±3.5)μV波幅明显升高(P<0.05)。结论:抑郁症患者存在P300异常,草酸艾司西酞普兰具有改善这种异常现象的作用。     

卒中后抑郁与抑郁症事件相关电位变化特点和对比研究

目的观察卒中后抑郁(post-stroke depression,PSD)和抑郁症患者事件相关电位失匹配负波(mismatch negative,MMN)和P300的变化特征。方法纳入卒中后抑郁患者28例,抑郁症患者35例,正常对照30名,均采用Oddball范式进行事件相关电位MMN和P300检测。结果3组MMN和P300潜伏期和波幅均具有统计学差异(P<0.05)。与对照组相比,卒中后抑郁组和抑郁症组MMN和P300潜伏期延长、波幅下降(P<0.05);卒中后抑郁组较抑郁症组MMN和P300潜伏期延长、波幅下降(P<0.05)。结论卒中后抑郁比抑郁症MMN和P300的潜伏期更长,波幅更低,可作为与抑郁症鉴别诊断的参考。     

抑郁症患者识别负性表情的脑磁源性影像动态变化

目的 利用磁源性影像技术以及表情事件相关识别实验范式探讨抑郁症患者识别负性动态表情的神经网络磁源性影像动态变化的特点.方法 利用脑磁图检测12例抑郁症患者(患者组)及12名年龄、性别、受教育年限近似匹配的健康对照者(对照组)识别负性动态表情视频时的脑部反应.设P＜0.01时,差异均具有统计学意义.结果 与对照组相比,患者组识别负性面部表情时,活动异常主要出现在双侧钩回、双侧颞上回、右额中回、右杏仁核、右颞回下、左梭状回、左枕下回、右海马旁回、左枕舌回、双侧楔前叶、左楔叶等脑区,这些脑区组成的神经网络在识别负性动态表情过程有相应脑区激活异常.结论 抑郁症患者识别负性表情的功能网络的脑磁源性影像动态变化特点与正常人比较差异有统计学意义.     

老年抑郁症患者脑磁共振波谱成像研究

目的 应用磁共振波谱成像(MRS)研究老年抑郁症患者脑内神经环路物质代谢异常,探讨其发病机制.方法 对23例老年抑郁症患者(抑郁症组)及18名老年健康志愿者(正常对照组)行常规磁共振及三维磁共振氢质子波谱(<'1>H-MRS)检查,测量双侧额叶背外侧白质、前部扣带回皮质、杏仁核、海马、丘脑的N-乙酰天门冬氨酸(N从)、胆碱(Cho)与肌酸(Cr)的比值,对两组各部位的比值分别进行独立样本t检验.结果 (1)抑郁症组额叶背外侧白质(2.28±0.32)、前部扣带回皮质(2.19 ±0.39)、杏仁核(1.95 ±0.22)、海马的Cho/Cr比值(2.38 ±0.30)均高于正常对照组(分别为1.88 ±0.40、1.68±0.30、1.66±0.24、2.00±0.34),差异有统计学意义(P＜0.01～0.05);而丘脑Cho/Cr比值与对照组的差异无统计学意义(P＞0.05).(2)抑郁症组前部扣带回皮质(2.08 ±0.26)、杏仁核(2.20 ±0.27)、海马的NAA/Cr比值(2.10 ±0.27)低于正常对照组(分别为2.58 ±0.35、2.52±0.22、2.44±0.24),差异有统计学意义(P＜0.01～0.05);而额叶背外侧白质及丘脑未见明显变化(P＞0.05).结论 老年抑郁症患者额叶背外侧白质、前部扣带回皮质、杏仁核、海马的Cho/Cr比值明显高于对照组,提示边缘系统-皮质-纹状体-苍白球-丘脑环路的功能受到影响,该神经环路在老年抑郁症发病机制中可能起一定作用.     

首、复发抑郁症患者额颞叶神经纤维偏侧化与疾病严重程度的相关研究

目的:探讨首、复发抑郁症患者额颞叶神经纤维是否存在偏侧化改变,以及与认知、疾病严重程度的相关性。方法:入组首发抑郁症患者25例、复发抑郁症患者27例及健康对照者24名,入组者均进行弥散张量成像扫描(DTI)及威斯康辛卡片分类测试(WCST);抑郁患者同时进行汉密尔顿抑郁量表(HAMD)评分。结果:首、复发抑郁组,在右额中回、右额下回、右颞下回的各向异性(FA)值较左侧显著性降低(P0.05),复发抑郁组右侧海马回FA值较左侧显著性升高(P0.01),健康对照组未发现左右脑FA值差异有统计学意义(P0.05);对照组左额叶中回、左额下回FA值与持续错误数正相关,右额下回FA值与完成第一分类所需应答数正相关,首发抑郁组的左额叶中回FA值与持续错误数相关,右额下回FA值与完成第一分类所需应答数相关(P均0.05);复发抑郁组右额下回FA值与HAMD评分呈负相关(P0.05)。结论:首、复发抑郁症患者均存在右侧颞叶、额叶的偏侧化,且与认知功能的改变存在一定的相关性,反复发作、病程迁延的复发患者偏侧化程度进一步加重,且右侧额叶下回的纤维完整性与疾病严重程度呈负相关。     

帕金森病伴抑郁症患者的事件相关电位研究

目的评价事件相关电位(ERP)对帕金森病伴抑郁症患者的诊断价值。方法应用听觉经典Oddball序列和视觉非经典Oddball序列分别对正常健康人、帕金森病不伴抑郁症患者、帕金森病伴抑郁症患者进行ERP检查,记录其电生理指标。结果听觉模式下诱发的P300潜伏期和波幅,3组间无明显差异;视觉模式下诱发的P450,帕金森病伴抑郁症组潜伏期较其他2组明显延长,波幅较其他2组明显降低;帕金森病伴抑郁症组患者潜伏期与汉密尔顿得分呈正相关(r=0.382,P<0.05),波幅与得分呈负相关(r=-0.412,P<0.05)。结论一定模式下的ERP对帕金森病伴抑郁症患者的诊断提供了较为可靠的电生理指标。     

前额叶-边缘环路theta波功能连接对抑郁症的识别作用

目的:探讨识别负性情绪面孔时前额叶-边缘环路theta波功能连接能否作为识别抑郁症的脑影像学特征。方法:利用脑磁图检测31例抑郁症患者(抑郁症组)及43名与其相匹配的健康人(正常对照组)在识别动态面部悲伤表情时的脑部电生理反应。通过一致性方法计算出感兴趣脑区间在300~600 ms的功能连接值,比较抑郁症组与正常对照组的功能连接差异,将感兴趣脑区功能连接矩阵作为特征用支持向量机进行分类,并与汉密尔顿抑郁量表(HAMD-17)评分作相关分析。结果:识别负性情绪面孔时感兴趣脑区theta波功能连接对抑郁症患者识别率为94.59%(P=0.0015)。在300~400 ms,抑郁症组右海马与左眶额叶上部(r=-0.49,P=0.0055)、与左眶额叶下部(r=-0.52,P=0.0022)的功能连接值与HAMD-17评分负相关;在500~600 ms,抑郁症组左海马与左扣带中部功能连接增强与HAMD-17评分呈正相关(r=0.62,P=0.002)。结论:在识别负性情绪面孔时前额叶-边缘环路感兴趣脑区的theta波功能连接有助于识别抑郁症。     

Effects of antidepressive therapy on auditory processing in severely depressed patients: a combined MRS and MEG study

BACKGROUND: Alterations in brain metabolism as well as in brain function in different brain areas can be observed in severely depressed patients. METHODS: The present study combined proton magnetic resonance spectroscopy (1H MRS, n=16; healthy controls n=27) and magnetoencephalography (MEG, n=17, controls n=18) of the left auditory cortex in severely depressed inpatients pre- and post successful antidepressive therapy. For MEG recordings, patients were stimulated with trains of 4 successive vowels or 4 sine tones, respectively. For each of the 4 stimuli, the amplitude and latency of the N1m was calculated. As a measure of habituation the decrease of the individual amplitudes of the second, third and fourth N1m compared to the first N1m was calculated. RESULTS: Prior to therapy, a subset of patients presented clearly disturbed auditory processing to stimuli (missing of distinct N1m1 and subsequent habituation; 5 of 17 patients (vowels) and 9/17 (tones, respectively)). After treatment, compared to controls, a normalized habituation pattern was observed in all patients for vowels, but not for tones. In contrast, MRS revealed no significant differences between the metabolite concentrations of patients and healthy controls in both measurements. CONCLUSION: Depression may be accompanied by impaired auditory processing, which seems to improve with reduction in depressive symptoms. Auditory cortical dysfunction probably reflects only a part from more widespread aberrations of brain function occurring with severe mood disorder.     

Perception of facial expressions of emotion in bipolar disorder

OBJECTIVES: Some studies have reported deficits in the perception of facial expressions among depressed individuals compared with healthy controls, while others have reported negative biases in expression perception. We examined whether altered perception of emotion reflects an underlying trait-like effect in affective disorder by examining facial expression perception in euthymic bipolar patients. METHODS: Sensitivity to six different facial expressions, as well as accuracy of emotion recognition, was examined among 17 euthymic bipolar patients and 17 healthy controls using an interactive computer program. RESULTS: No differences were found between euthymic bipolar patients and controls in terms of sensitivity to any particular emotion. Although initial analysis of the data suggested impairment in the recognition of fear among the patients, identification of this emotion was not relatively impaired compared with that of the other emotions. CONCLUSIONS: The study did not find any conclusive evidence for trait-like deficits in the perception of facially conveyed emotions in bipolar disorder. Altered perception of facial expressions that has been found to accompany depressed mood may instead reflect mood-congruent biases.     

Distributed source modeling of language with magnetoencephalography: Application to patients with intractable epilepsy

Purpose:   To examine distributed patterns of language processing in healthy controls and patients with epilepsy using magnetoencephalography (MEG), and to evaluate the concordance between laterality of distributed MEG sources and language laterality as determined by the intracarotid amobarbital procedure (IAP).
Methods:   MEG was performed in 10 healthy controls using an anatomically constrained, noise-normalized distributed source solution (dynamic statistical parametric map, dSPM). Distributed source modeling of language was then applied to eight patients with intractable epilepsy. Average source strengths within temporoparietal and frontal lobe regions of interest (ROIs) were calculated, and the laterality of activity within ROIs during discrete time windows was compared to results from the IAP.
Results:   In healthy controls, dSPM revealed activity in visual cortex bilaterally from ∼80 to 120 ms in response to novel words and sensory control stimuli (i.e., false fonts). Activity then spread to fusiform cortex ∼160–200 ms, and was dominated by left hemisphere activity in response to novel words. From ∼240 to 450 ms, novel words produced activity that was left-lateralized in frontal and temporal lobe regions, including anterior and inferior temporal, temporal pole, and pars opercularis, as well as bilaterally in posterior superior temporal cortex. Analysis of patient data with dSPM demonstrated that from 350 to 450 ms, laterality of temporoparietal sources agreed with the IAP 75% of the time, whereas laterality of frontal MEG sources agreed with the IAP in all eight patients.
Discussion:   Our results reveal that dSPM can unveil the timing and spatial extent of language processes in patients with epilepsy and may enhance knowledge of language lateralization and localization for use in preoperative planning.     

Oscillatory cortical drive to isometrically contracting muscle in Unverricht-Lundborg type progressive myoclonus epilepsy (ULD)

OBJECTIVE: We investigated with whole-scalp magnetoencephalography (MEG) oscillatory cortical drive to isometrically contracting muscle in 8 genetically verified, and thus etiologically homogeneous, Unverricht-Lundborg type progressive myoclonus epilepsy (ULD) patients suffering from cortical myoclonus and generalized tonic-clonic seizures. The results were compared with those of 8 healthy control subjects. METHODS: Cortical MEG signals were measured simultaneously with surface electromyography (EMG) during isometric contraction of the left and right first dorsal interosseus muscles. Cortex-muscle coherence and cross-correlograms between MEG and EMG signals were calculated as indicators of oscillatory cortical drive to muscle. The cortical areas involved in the maximum cortex-muscle coherence were also identified. RESULTS: In patients, the strengths of the dominant coherent peaks were 2-4 fold compared with the healthy controls. Whereas the coherence was found strictly in the contralateral primary motor cortex in controls, additional coherent activity was observed ipsilaterally in 5 out of 8 patients. CONCLUSIONS: The remarkably increased MEG-EMG coherence in ULD patients suggests altered oscillatory cortical drive to the muscle during isometric contraction. We suggest that the enhanced cortex-muscle coherence in ULD patients reflects reduced inhibition in the motor cortex, and may contribute to disturbed voluntary movements.     

抑郁症晨重夕轻特征与生物学的关系

目的:探讨抑郁症患者临床症状晨重夕轻的特征与血浆皮质醇、细胞因子浓度的关系。方法:采用放射免疫法、酶联免疫吸附法对55例双相障碍(抑郁相)和抑郁发作诊断标准的抑郁症患者及38名正常对照组早7:00、晚7:00血浆皮质醇、IL-6、IL-2浓度进行测定,比较各指标早、晚浓度及早晚差值在抑郁症晨重夕轻组和无晨重夕轻组以及正常对照组的差异。结果:抑郁症晨重夕轻组和无晨重夕轻组早间的皮质醇浓度、早晚之间的皮质醇浓度差值均较正常对照组显著增高;晨重夕轻组晚间的血IL-6浓度较正常对照组显著增高,两组的IL-6早晚的差值与正常对照组相比有显著性差异;晨重夕轻组和无晨重夕轻组晚间IL-2水平均明显低于正常对照组。结论:抑郁症患者不管临床症状有无晨重夕轻的特征,均存在血浆皮质醇浓度早晨高于晚上和血浆IL-6浓度晚上高于早晨的异常改变。     

Further investigation on benzodiazepine binding inhibitory activity in patients with major depression or panic disorder and in healthy volunteers

Preliminary findings regarding the presence of plasmatic benzodiazepine binding inhibitory activity (BBIA) in 14 psychiatric patients prompted us to investigate it further in larger samples of psychiatric patients (n = 44) and in healthy controls (n = 14). The results have shown that BBIA is present in all the subjects included with statistically significant differences between the patients and controls. The highest concentrations were found in the patients with no difference between anxious or depressed patients, and the lowest in the healthy controls. These findings indicate that BBIA might play a role in the pathophysiology of some manifestations of anxiety.     

Raised plasma levels of tumor necrosis factor alpha in patients with depression: normalization during electroconvulsive therapy

OBJECTIVE: To examine whether electroconvulsive therapy (ECT) could modulate tumor necrosis factor (TNF)alpha levels in patients with depressive disorders. METHOD: Plasma levels of TNFalpha were analyzed in 23 depressed patients, mainly with severe depressive disorders, and in 15 sex- and age-matched healthy controls. Fifteen depressed patients were followed longitudinally with measurement of TNFalpha before, during, and after repeated ECT treatment. For comparison, TNFalpha levels were also analyzed longitudinally in the 8 depressed patients not receiving ECT. RESULTS: Patients with depressive disorders had markedly raised TNFalpha levels compared with healthy controls. The clinical improvement during repeated ECT was accompanied by a gradual and significant decline in TNFalpha level, reaching levels comparable with those in healthy controls at the end of the study. Such a decline was not seen in the depressed patients not receiving ECT, who instead showed raised TNFalpha levels throughout the study period. CONCLUSION: Our findings support an association between inflammation and TNFalpha in particular and severe depression, and suggest that ECT may down-regulate this immune activation.     

Life events associated with major depression in Ugandan primary healthcare (PHC) patients: issues of cultural specificity

OBJECTIVE: The study compared life events experienced by depressed patients seen at primary healthcare (PHC) centres with those among healthy community controls. METHOD: Data was collected from 74 depressed patients and 64 unmatched controls from village locales of patients. Interview instruments included the depression module of the Mini International Neuropsychiatric Interview (MINI) and Interview for Recent Life Events (IRLE). Associations between type of respondent and demographic variables were examined. Statistical comparisons were done for the two groups on other variables. RESULTS: Most depressed patients were single by marital status, lacked formal employment and had less post-primary education.They had experienced more life events; job changes, discomforting working hours, unfavourable working conditions, and job losses; personal health problems; loss of valuables; difficulties with intimate partners and family members' marital problems. Independent life events were more among depressed patients and clustered around work, health, bereavement and marriage. Most events reported by depressed patients had high negative impact ratings compared to controls. CONCLUSION: Compared to healthy community controls, depressed patients reported more undesirable life events. The relationship between life events and depression implies that in PHC settings of poor countries, deploying mental health-oriented workers to manage life events may lessen escalation of distress.     

Resting state oscillatory brain dynamics in Parkinson's disease: an MEG study.

OBJECTIVE: The pathophysiological mechanisms of cognitive dysfunction and dementia in Parkinson's disease (PD) are still poorly understood. Altered resting state oscillatory brain activity may reflect underlying neuropathological changes. The present study using magneto encephalography (MEG) was set up to study differences in the pattern of resting state oscillatory brain activity in groups of demented and non-demented PD patients and healthy, elderly controls. METHODS: The pattern of MEG background oscillatory activity was studied in 13 demented PD patients, 13 non-demented PD patients and 13 healthy controls. Whole head MEG recordings were obtained in the morning in an eyes closed and an eyes open, resting state condition. Relative spectral power was calculated using Fast Fourier Transformation in delta, theta, alpha, beta and gamma frequency bands. RESULTS: In the non-demented PD patients, relative theta power was diffusely increased and beta power concomitantly decreased relative to controls. gamma Power was decreased in central and parietal channels. In the demented PD patients, a diffuse increase in relative delta and to lesser extent theta power and a decrease in relative alpha, beta and to lesser extent gamma power were found in comparison to the non-demented PD group. In addition, reactivity to eye opening was much reduced in the demented PD group. CONCLUSIONS: Parkinson's disease is characterized by a slowing of resting state brain activity involving theta, beta and gamma frequency bands. Dementia in PD is associated with a further slowing of resting state brain activity, additionally involving delta and alpha bands, as well as a reduction in reactivity to eye-opening. SIGNIFICANCE: The differential patterns of slowing of resting state brain activity in demented and non-demented PD patients suggests that, in conjunction with a progression of the pathological changes already present in non-demented patients, additional mechanisms are involved in the development of dementia in PD.