额叶癫(癎)执行功能损害及磁共振弥散张量成像研究

目的用磁共振弥散张量成像技术研究额叶癫患者执行功能损害的相关脑区及病理改变,探讨其可能的发生机制。方法对32例成人额叶癫患者和75例正常健康对照者进行神经心理检查,并对18例常规影像无病灶的额叶癫患者和20例正常健康对照者进行弥散张量成像扫描及统计分析。结果额叶癫患者组语义流畅性明显差于对照组,数字广度测验得分和90min正确填写数字符号个数明显低于对照组。与对照组比较,额叶癫患者右侧额叶MD值明显高于对照组;右侧外囊、尾状核和双侧丘脑的FA值明显低于对照组,差异具有显著性意义。相关分析显示双侧内囊前肢、左侧外囊、左枕叶皮质下白质FA值与语义流畅性呈正相关。左侧内囊膝部、内囊后肢和丘脑MD值与MMSE呈负相关;双侧内囊前肢、左侧外囊、额叶、枕叶相应白质内FA值与MMSE呈正相关。结论DTI显示额叶癫患者右侧额叶MD值明显增高、右侧外囊、尾状核和双侧丘脑的FA值明显减低,提示额叶癫患者在上述区域可能存在细微病理改变,执行功能可能超出前额叶的范围。     

The executive control of attention differentiates patients with schizophrenia, their first-degree relatives and healthy controls

Attentional and executive impairments have been reported in patients with schizophrenia and in their healthy first-degree relatives. However, its nature remains unclear and discrepancies between studies have been observed. These might be due to differences in the clinical severity of the illness or in sociodemographic factors. The objective of the present work was to explore the efficiency of three attention networks: alerting, orienting and executive control (conflict inhibition) defined anatomically, using patients, their relatives and controls, assessing the possibility to use them as endophenotypes. We used three tests, the Attention Network Test (ANT), the Wisconsin Card Sorting Test (WCST) and the Stroop Test, and compared 52 patients with schizophrenia, 55 of their first-degree relatives and 53 unrelated healthy controls, taking into account demographic variables (age, sex and years of education) and clinical symptoms of schizophrenia. Patients had a longer overall mean reaction-time (p < 0.001), and took longer to resolve the ANT conflict (ANTc) (p = 0.04) than the control group. In the schizophrenia group, the SSPI disorganization score was significantly correlated to the ANTc performance. Additionally, first-degree relatives of patients with schizophrenia also performed significantly worse than controls in attention performance test. Our findings support a specific deficit in executive control of attention in patients with schizophrenia. This deficit was shown to be correlated with the intensity of the disorganization score in patients. Relative presented an intermediate phenotype between patients and controls; the ANT reaction time (but not the ANTc) may thus be considered as possible endophenotype marker for schizophrenia.     

Subcortical hyperintensities in Alzheimer's disease: no clear relationship with executive function and frontal perfusion on SPECT

BACKGROUND/AIMS: To investigate relationships between subcortical hyperintensities (SH), frontal perfusion and executive function (EF) in a sample of Alzheimer's disease (AD) patients with varying severities of SH. METHODS: A sample of 63 AD patients underwent brain imaging with magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) scans. Severity of SH was assessed using a standardized visual rating scale on MRI. Patients were classified into severe (n=20), moderate (n=23) or no SH (n=20) groups. Four frontal SPECT regions of interest (anterior cingulate cortex, dorsolateral prefrontal cortex) and neuropsychological assessment of EF were analyzed. RESULTS: Overall, no significant relationships were found between severity of SH and measures of SPECT perfusion or EF, except for one subsection of the Dementia Rating Scale, with severe SH scoring slightly worse than the other two groups. CONCLUSION: These findings support previous studies which suggest minimal adverse effects of SH on brain function and cognition. Global severity of SH on MRI in AD was not associated with decline in frontal perfusion and only mildly related to a decline in a specific EF task. More accurate measures of SH volume, not just global severity of SH, may be necessary to capture such complex brain behavior relationships; if they do indeed exist.     

Interictal regional slow activity in temporal lobe epilepsy correlates with lateral temporal hypometabolism as imaged with 18FDG PET: neurophysiological and metabolic implications

OBJECTIVES—Thephenomenon of interictal regional slow activity (IRSA) in temporal lobeepilepsy and its relation with cerebral glucose metabolism, clinicaldata, MRI, and histopathological findings was studied.
METHODS—Interictal¹⁸F-fluorodeoxyglucose positron emission tomography(FDG PET) was performed under continuous scalp EEG monitoring in 28 patients with temporal lobe epilepsy not associated with intracranialforeign tissue lesions, all of whom subsequently underwent resectivesurgery. Regions of interest (ROIs) were drawn according to a standardtemplate. IRSA was considered lateralised when showing a 4:1 or greaterratio of predominance on one side.
RESULTS—Sixteenpatients (57%) had lateralised IRSA which was always ipsilateral tothe resection and of maximal amplitude over the temporal areas. Itspresence was significantly related to the presence of hypometabolism inthe lateral temporal neocortex (p=0.0009). Logistic regression of theasymmetry indices for all measured cerebral regions confirmed a strongassociation between IRSA and decreased metabolism of the posteriorlateral temporal neocortex only (p=0.009). No significant relationcould be shown between slow activity and age at onset, duration of theepilepsy, seizure frequency, and MRI evidence for hippocampal atrophy.Furthermore, IRSA was not specifically related to mesial temporalsclerosis or any other pathology.
CONCLUSIONS—Interictalregional slowing in patients with temporal lobe epilepsy not associatedwith a mass lesion is topographically related to the epileptogenic areaand therefore has a reliable lateralising, and possibly localising,value. Its presence is irrelevant to the severity or chronicity of theepilepsy as well as to lateral deactivation secondary to neuronal lossin the mesial temporal structures. Although slow EEG activity isgenerally considered as a non-specific sign of functional disturbance,interictal regional slowing in temporal lobe epilepsy should beconceptualised as a distinct electrographic phenomenon which isdirectly related to the epileptogenic abnormality. The strongcorrelation between interictal regional slowing and lateral temporalhypometabolism suggests in turn that the second may delineate a fieldof reduced neuronal inhibition which can receive interictal and ictal propagation.

     

Investigating the relationship between sexual and chemical addictions by comparing executive function in subjects with pedophilia or opiate addiction and healthy controls

Disorders of driven sexual behavior have been conceptualized as sexual addictions. In the following study, we compared 51 subjects with pedophilia, 53 subjects with opiate addiction, and 84 healthy control subjects on neuropsychological tests that tap executive functions. The test battery included the Wisconsin Card Sorting Test (WCST), Stroop Color-Word Test, the Matching Familiar Figures Test (MFFT), Porteus Mazes, Controlled Word Association (COWA), and Trailmaking Test. The groups differed on tests of cognitive flexibility and set switching (WCST), sustained attention (Stroop), and impulsivity (MFFT and Porteus Mazes). There were no differences on verbal fluency (COWA). The subjects with pedophilia differed significantly from those with opiate addiction on several tests, with longer latency to response on MFFT and fewer completed mazes but also fewer errors on Porteus Mazes. Thus, while both subjects with pedophilia and those with opiate addiction show executive dysfunction, the nature of that dysfunction may differ between the two groups; specifically, opiate addicted subjects may be more prone to cognitive impulsivity.     

The combined burden of cognitive, executive function, and psychosocial problems in children with epilepsy: a population-based study

The combined burden of psychosocial (Achenbach scales), cognitive (Raven matrices), and executive function (EF) problems was studied in a population-based sample of 6- to 12-year-old children with epilepsy (n=162; 99 males, 63 females) and in an age- and sex-matched control group (n=107; 62 males, 45 females). Approximately 35% of the children with epilepsy had severe non-verbal cognitive problems. In those that did not, mild cognitive problems (26% vs 11%, p=0.005), EF problems (31% vs 11%, p<0.001), and psychosocial problems (45% vs 10%, p<0.001) were each much more common than among controls. Having problems in two or all three of these areas simultaneously was more frequent among the children with epilepsy (14% vs. 3%, p<0.001 and 4% vs 0%, p<0.001 respectively). Excluding those having remote symptomatic epilepsy aetiology did not change the problem load significantly for the children with epilepsy with the important exception that having severe non-verbal problems was approximately halved from 35 to 18%. In 30 children with benign epilepsy of childhood with centrotemporal spikes, mild cognitive problems were somewhat more common, but psychosocial and EF problems were similar compared with control children.     

Genetic influences of resting state fMRI activity in language-related brain regions in healthy controls and schizophrenia patients: a pilot study

Individuals with schizophrenia show a broad range of language impairments, similar to those observed in reading disability (RD). Genetic linkage and association studies of RD have identified a number of candidate RD-genes that are associated with neuronal migration. Some individuals with schizophrenia also show evidence of impaired cortical neuronal migration. We have previously linked RD-related genes with gray matter distributions in healthy controls and schizophrenia. The aim of the current study was to extend these structural findings and to examine links between putative RD-genes and functional connectivity of language-related regions in healthy controls (n?=?27) and schizophrenia (n?=?28). Parallel independent component analysis (parallel-ICA) was used to examine the relationship between language-related regions extracted from resting-state fMRI and 16 single nucleotide polymorphisms (SNPs) spanning 5 RD-related genes. Parallel-ICA identified four significant fMRI-SNP relationships. A Left Broca-Superior/Inferior Parietal network was related to two KIAA0319 SNPs in controls but not in schizophrenia. For both diagnostic groups, a Broca-Medial Parietal network was related to two DCDC2 SNPs, while a Left Wernicke-Fronto-Occipital network was related to two KIAA0319 SNPs. A Bilateral Wernicke-Fronto-Parietal network was related to one KIAA0319 SNP only in controls. Thus, RD-genes influence functional connectivity in language-related regions, but no RD-gene uniquely affected network function in schizophrenia as compared to controls. This is in contrast with our previous study where RD-genes affected gray matter distribution in some structural networks in schizophrenia but not in controls. Thus these RD-genes may exert a more important influence on structure rather than function of language-related networks in schizophrenia.     

Differences in resting energy expenditure and body composition between patients with schizophrenia and healthy controls

OBJECTIVE: A lowered energy metabolism in schizophrenia was reported already in the 1920s. However, these early investigations were case studies without control groups or statistical analysis. In this study the resting energy expenditure (REE) and relevant body composition variables were measured in patients with schizophrenia and healthy controls. METHOD: REE was determined in 30 patients and 17 controls. The difference between the measured and the expected level for each individual was calculated as DeltaREE. Body composition was assessed with bioelectrical impedance and calliper measurements. RESULTS: DeltaREE was significantly lower in the patients than in the controls. A decrease was also seen in the non-medicated patients. The patients showed significantly lower percentages of water in fat free-mass and intracellular water. CONCLUSION: The lowering of REE and body water fractions may suggest a homeostatic aberration in schizophrenia that may be of importance for the understanding of metabolic disturbances observed in the disease.     

Mirtazapine increases cortical excitability in healthy controls and epilepsy patients with major depression

BACKGROUND: Epilepsy is often complicated by depression requiring antidepressant treatment. Such treatment might be proconvulsive. OBJECTIVE: To examine the effects of the noradrenergic and specific serotonergic antidepressant mirtazapine on motor cortex excitability in epilepsy patients with depression and in healthy controls, using transcranial magnetic stimulation (TMS). METHODS: Seven clinically depressed epilepsy patients treated with anticonvulsant drugs and six healthy volunteers were studied. Before intake of mirtazapine and 24 hours afterwards (and also three weeks afterwards in the patients), the active and resting motor threshold (AMT, RMT), the size of the motor evoked potential (MEP), the cortical silent period (SP), and intracortical inhibition/facilitation and intracortical facilitatory I wave interactions were determined using single and paired pulse TMS. RESULTS: At baseline, AMT and RMT were higher (p = 0.049 and p = 0.04, respectively) and the ratio SP duration/MEP area greater in patients (p = 0.041). In patients but not in healthy subjects AMT was lower 24 hours after intake of mirtazapine (p = 0.028). Mirtazapine had no significant effect on the MEP size, duration of the SP, or the ratio of SP duration to MEP size in patients. The duration of the SP was longer (p = 0.037) but the ratio of SP duration to MEP size remained similar in healthy subjects after mirtazapine. There were no significant differences in paired pulse measures between the two groups either at baseline or after mirtazapine. CONCLUSIONS: Mirtazapine increased neuronal excitability of pyramidal tract axons in an activated state in both healthy controls and epilepsy patients with major depression.     

癫痫患者认知功能与睡眠质量的关系

目的 探讨癫痫患者认知功能与睡眠质量的关系.方法 对50例癫痫患者(试验组)及40例正常人(对照组)行蒙特利尔认知评估量表(MoCA)、Epworth嗜睡量表(ESS)和匹兹堡睡眠质量指数问卷(PSQI)评定,分析认知功能与睡眠质量的关系.结果 试验组与对照组认知功能障碍、嗜睡和睡眠紊乱检出例数分别为:42/50(84.00%):3/40(7.50%)(P＜0.05)、26/50(52.00%):9/40(22.50%)(P＜0.05)和13/50(26.00%):5/40(12.50%)(P＜0.05).两组患者的MoCA总分、MoCA 7个子项目、ESS总分、PSQI总分、PSQI子项目睡眠效率和睡眠障碍计分比较,差异有统计学意义(P＜0.05).相关分析显示MoCA总分与身高和文化程度呈正相关(r分别为0.361和0.321,P＜0.05),与年龄和发作频率呈负相关(r分别为-0.273和-0.271,P＜0.05).MoCA子项目记忆力和抽象能力分别与PSQI子项目催眠药物和日间功能障碍呈负相关(r分别为-0.262和-0.270,P＜0.05).结论 癫痫患者存在认知功能障碍和睡眠紊乱,癫痫患者认知功能影响因素有身高、文化程度、年龄和发作频率,记忆力和抽象能力分别与催眠药物及日间功能障碍相关.     

Usefulness of PET scan in a child with mesial frontal lobe epilepsy.

Positron emission tomography (PET) scan with 18F-fluorodeoxyglucose (18F-FDG) was performed in a 14-year-old boy who had seizures suspected to have originated in mesial frontal lobe. The seizures occurred in clusters and were characterised by a change in the facial expression at seizure onset and complex motor manifestations consisting of kicking, swaying and screaming. Ictal EEG showed rhythmic alpha-waves in the left frontal area association with the ictus. Cerebral CT, MRI and SPECT revealed nothing of significance, but the PET brain scans showed frontal and parietal hypometabolism, which was most prominent in the left mesial frontal lobe. The present case suggests that FDG-PET scanning may be useful for the diagnosis of the mesial frontal epilepsy, when other imaging studies fail to show abnormalities.     

首发精神分裂症患者静息态脑局部一致性功能性磁共振研究

目的:应用功能性磁共振(f MRI)技术,探讨首发精神分裂症患者静息状态下脑局部一致性(Re Ho)功能变化的特征。方法:对首发未用药精神分裂患者(急性期组)及性别、年龄、受教育年限匹配的经抗精神病药治疗后症状缓解的首发精神分裂症患者(缓解组)各17例,分别进行f MRI扫描,利用Re Ho的方法分析数据,比较两组间Re Ho变化。结果:与急性期组相比,缓解期组表现出右侧颞上回、舌回/梭状回、左侧和右侧额下回、左侧和右侧中央后回、小脑等脑区局部一致性异常,均有统计学意义(P均0.05)。结论:缓解期组较急性期组相比,多个脑区有相应的局部一致性异常,这种脑功能特征的变化,可能与抗精神病药改善症状有关,且可能反映精神分裂症生物内表型的变化。     

Memory and executive functions in healthy subjects and patients with multiple sclerosis: the role of PET and SPECT

Despite extensive research, the precise role of different brain areas in modulating attentional and mnemonic processes is still controversial. Using positron emission tomography (PET) or single photon emission computed tomography (SPECT), we can measure changes which are associated with the level of neuronal activity in normal subjects and in patients. We describe the pattern of activation in attentional processes, with respect to three basic components: vigilance, selective attention and attentional processing capacity. Furthermore, we underline the predominant role of frontal and temporal cortices that mediate different activities associated with memory function.Functional techniques have substantially contributed to a better understanding of the cognitive deficits associated with multiple sclerosis (MS), suggesting that cortical- subcortical disconnection is the most likely cause of the neuropsychological deficits. The difficulties in attempting to attribute specific cognitive abnormalities to focal brain pathology in presence of widespread disease such as MS will probably be attenuated by functional neuroimaging studies.     

Sex differences in face recognition memory in patients with temporal lobe epilepsy, patients with generalized epilepsy, and healthy controls

The influence of sex on face recognition memory was studied in 49 patients with temporal lobe epilepsy, 20 patients with generalized epilepsy, and 32 healthy controls. After learning 20 faces, serially presented for 5 seconds each, subjects had to recognize the 20 among 40 faces (including 20 new faces) immediately and 24 hours later. Women had better face recognition than men, with no significant differences between groups. Women's advantage was due mainly to superior delayed recognition. Taken together, the results suggest that sex has a similar impact on face recognition in patients with epilepsy and healthy controls, and that testing delayed face recognition raises sensitivity for sex differences. The influence of sex on face recognition in patients with epilepsy should be acknowledged when evaluating individuals or comparing groups.     

轻度颅脑损伤患者执行功能障碍研究

目的探讨轻度颅脑损伤(mild traumatic brain injury,m TBI)患者伤后执行功能(executive function,EF)的动态变化特点。方法对63例m TBI患者(研究组)在伤后1周、1个月、3个月和6个月进行执行功能测查,并与60例健康受试者(对照组)比较。测查工具采用连线测验(trail making test,TMTA)、霍普金斯词语学习测验修订版(Hopkins verbal learning test-revised,HVLT-R)、简易视觉记忆测验—修订版(brief visuospatial memory test-revised,BVMT-R)、Stroop色词测验、持续操作测验(continuous performance test,CPT)。结果伤后1周与对照组比较,TMTA、HVLT-R、BVMT-R、Stroop和CPT-IP分值差异有统计学意义(P0.05);与伤后1周相比,伤后1个月、3个月和6个月时的TMTA分值下降,HVLT-R、BVMT-R、Stroop和CPT-IP分值增加(P0.05)。组内两两比较,伤后1个月与伤后1周比较,TMTA分值下降,BVMT-R、Stroop分值增加(P0.05);伤后3个月与伤后1个月比较,Stroop、BVMT-R和CPT-IP分值增加(P0.05);伤后6个月与伤后3个月比较,Stroop和CPTIP分值增加(P0.05)。结论m TBI患者在注意能力/警觉性、学习与工作记忆、信息处理速度及执行功能上都可能存在一定的损害,伤后不同时间点恢复速度并不一致。     

Hemodynamic correlates of emotion regulation in frontal lobe epilepsy patients and healthy participants

The ability to regulate emotions is indispensable for maintaining psychological health. It heavily relies on frontal lobe functions which are disrupted in frontal lobe epilepsy. Accordingly, emotional dysregulation and use of maladaptive emotion regulation strategies have been reported in frontal lobe epilepsy patients. Therefore, it is of clinical and scientific interest to investigate emotion regulation in frontal lobe epilepsy. We studied neural correlates of upregulating and downregulating emotions toward aversive pictures through reappraisal in 18 frontal lobe epilepsy patients and 17 healthy controls using functional magnetic resonance imaging. Patients tended to report more difficulties with impulse control than controls. On the neural level, patients had diminished activity during upregulation in distributed left‐sided regions, including ventrolateral and dorsomedial prefrontal cortex, angular gyrus and anterior temporal gyrus. Patients also showed less activity than controls in the left precuneus for upregulation compared to downregulation. Unlike controls, they displayed no task‐related activity changes in the left amygdala, whereas the right amygdala showed task‐related modulations in both groups. Upregulation‐related activity changes in the left inferior frontal gyrus, insula, orbitofrontal cortex, anterior and posterior cingulate cortex, and precuneus were correlated with questionnaire data on habitual emotion regulation. Our results show that structural or functional impairments in the frontal lobes disrupt neural mechanisms underlying emotion regulation through reappraisal throughout the brain, including posterior regions involved in semantic control. Findings on the amygdala as a major target of emotion regulation are in line with the view that specifically the left amygdala is connected with semantic processing networks.     

Interictal and ictal magnetoencephalographic study in patients with medial frontal lobe epilepsy

PURPOSE: To determine whether magnetoencephalography (MEG) has any clinical value for the analysis of seizure discharges in patients with medial frontal lobe epilepsy (FLE). METHODS: Four patients were studied with 74-channel MEG. Interictal and ictal electroencephalographic (EEG) and MEG recordings were obtained. The equivalent current dipoles (ECDs) of the MEG spikes were calculated. RESULTS: In two patients with postural seizures, interictal EEG spikes occurred at Cz or Fz. The ECDs of interictal MEG spikes were localized around the supplementary motor area. In the other two patients with focal motor or oculomotor seizures, interictal EEG spikes occurred at Fz or Cz. The ECDs of interictal MEG spikes were localized at the top of the medial frontal region. The ECDs detected at MEG ictal onset were also localized in the same area as those of the interictal discharges. CONCLUSIONS: In medial FLE patients, interictal and ictal MEG indicated consistent ECD localization that corresponded to the semiology of clinical seizures. Our findings demonstrate that MEG is a useful tool for detecting epileptogenic focus.