The differential effects of thalamus and basal ganglia on facial emotion recognition

This study examined if subcortical stroke was associated with impaired facial emotion recognition. Furthermore, the lateralization of the impairment and the differential profiles of facial emotion recognition deficits with localized thalamic or basal ganglia damage were also studied. Thirty-eight patients with subcortical strokes and 19 matched normal controls volunteered to participate. The participants were individually presented with morphed photographs of facial emotion expressions over multiple trials. They were requested to classify each of these morphed photographs according to Ekman's six basic emotion categories. The findings indicated that the clinical participants had impaired facial emotion recognition, though no clear lateralization pattern of impairment was observed. The patients with localized thalamic damage performed significantly worse in recognizing sadness than the controls. Longitudinal studies on patients with subcortical brain damage should be conducted to examine how cognitive reorganization post-stroke would affect emotion recognition.     

Visual neglect in the first weeks after a stroke in the right hemisphere

The aim of the study was to characterize symptoms of visual neglect among patients who recently survived a stroke in the right hemisphere (RH), and to contribute to the understanding of change in symptoms during the first months after a RH stroke. Thirteen patients with a RH stroke and twenty controls were assessed by using standard neglect tests. Five patients were followed up by repetitive test sessions during the next four months. To assess more subtle symptoms, reaction-time (RT) measures derived from an experimental cue-target paradigm were included in the final test session. A high frequency of neglect symptoms was documented at the first test session. The changes in performance during the first weeks were characterized by a high inter-individual as well as a high intra-individual variability. Although the remission rate on standard tests was high in the follow-up study, the RT measures indicated sustained symptoms of visual extinction in all patients. The long-term implication of the changes of neglect symptoms during the first weeks after a stroke and signs of sustained symptoms of visual extinction calls for further longitudinal studies including a larger group of patients.     

结构对称性汉字视觉识别特点的实验研究

用命名作业通过二个实验考察了结构对称性汉字的视觉识别特点,结果表明,汉字识别具有显著的结构对称性效应,识别结构对称性汉字的加工明显快于非对称性汉字,对称性效应与字频效应,笔画效应具有显著的交互作用,进一步的简单效应的分析表明,这种结构对称性效应在低频字中起作用,而在高频字中不起显著作用;在多笔画字中起作用,而在少毛画字中不起显著作用,这表明,对称性汉字中的具有冗余信息的格式塔部件促进地识别汉字的加     

不同部件亮度条件下的汉字识别初探

本文采用命名作业法探讨在不同汉字部件亮度条件下的字频效应、笔画数效应及部件在汉字识别中的作用。结果表明 :1在本实验条件下 ,字频效应仍非常明显 ,但没有笔画数效应 ;2在上下型汉字的识别中 ,其上半部的作用比下半部更为重要 ,而对左右型汉字而言 ,其右半部的作用比左半部更为重要 ;3部件亮度条件对命名反应时有显著影响 ,但是否可以称为“部件亮度效应”尚值得进一步研究。     

汉字通透性算法以及对结构方式效应的解释

在先前提出的汉字通透性算法中 ,包括了水平通透性和垂直通透性 ,而汉字作为整体 ,其通透性也应该是一个整体 ,所以 ,当前研究对这一算法进行了更正 ,然后运用新的算法对先前实验材料和基本汉字集 (6 72 4 )中的配对上下字和左右字进行通透性分析 ,证明了它的可行性。在实验研究中 ,采用新算法选择实验用字 ,以达到使上下字的通透性大于左右字的通透性或者使它们相等的目的 ,以此为前提观察到了逆转的结构方式效应以及结构方式效应消失。这一实验结果表明 ,结构方式本身并不影响汉字识别 ,影响汉字识别的直接因素是隐藏在结构方式之下的汉字通透性     

联合预防阿尔茨海默病与缺血性脑卒中的构想

阿尔茨海默病（AD）与缺血性脑卒中（IS）是中枢神经系统常见的两种高发病率和高致残率疾病。传统观点认为这两种疾病的病因、发病机制、病理生理以及临床表现均截然不同,长期以来它们的预防工作是分别展开的。随着 AD 研究的不断深化,AD 与 IS 之间的共性也不断增多,AD 可能与 IS 有着共同的血管相关发病机制以及相似的预防措施。为此,结合近年来 AD 血管机制领域的研究进展,提出 AD 与 IS 联合预防的新概念,并探讨了最佳的开始时间和预防策略。     

Global cognitive function before,surrounding, and after ischemic stroke: the role of risk and protective factors varies with time among ischemic stroke survivors

An estimated 65% of individuals demonstrate multidomain cognitive impairment poststroke, although little is known about the varying role of cognitive risk and protective factors in preischemic, peri-ischemic, and postischemic stroke phases. Longitudinal changes in global cognitive function after ischemic stroke are not well characterized, especially in older adults over age 80. We examined global cognitive function trajectories in these three phases across a mean follow-up of 8.12 (2.30) years in 159 female stroke survivors aged 65–79 at baseline using linear mixed models with change points. In separate models controlling for demographic variables, we tested the interaction of baseline risk and protective factors with stroke phase on global cognitive function. None of the prestroke global cognitive function means or trajectories differed significantly. At the time of ischemic stroke, higher body mass index (BMI), the presence of hypertension (HTN), low optimism, and higher physical function were all associated with significantly greater mean decreases in global cognition (all p’s <.0.0001), but were not significantly different from the contrasting level (all p’s >0.05). Higher BMI, the presence of HTN, low optimism, and higher physical function were in turn protective of global cognitive decline postischemic stroke (all contrasting p values <.01). Baseline factors may play either a risk or a protective role in global cognitive function depending on the phase of ischemic stroke.     

The neural underpinnings of facial emotion recognition in ischemic stroke patients

Deficits in facial emotion recognition occur frequently after stroke, with adverse social and behavioural consequences. The aim of this study was to investigate the neural underpinnings of the recognition of emotional expressions, in particular of the distinct basic emotions (anger, disgust, fear, happiness, sadness and surprise). A group of 110 ischaemic stroke patients with lesions in (sub)cortical areas of the cerebrum was included. Emotion recognition was assessed with the Ekman 60 Faces Test of the FEEST. Patient data were compared to data of 162 matched healthy controls (HC’s). For the patients, whole brain voxel-based lesion–symptom mapping (VLSM) on 3-Tesla MRI images was performed. Results showed that patients performed significantly worse than HC’s on both overall recognition of emotions, and specifically of disgust, fear, sadness and surprise. VLSM showed significant lesion–symptom associations for FEEST total in the right fronto-temporal region. Additionally, VLSM for the distinct emotions showed, apart from overlapping brain regions (insula, putamen and Rolandic operculum), also regions related to specific emotions. These were: middle and superior temporal gyrus (anger); caudate nucleus (disgust); superior corona radiate white matter tract, superior longitudinal fasciculus and middle frontal gyrus (happiness) and inferior frontal gyrus (sadness). Our findings help in understanding how lesions in specific brain regions can selectively affect the recognition of the basic emotions.