精神分裂症病人对成人面部表情的辨别

本文对比研究了精神分裂症病人和正常人对成人面部表情辨别的水平,发现精神分裂症病人存在着表情辨别障碍。病程长、以阴性症状为主的病人易出现这种障碍。表情辨别障碍是一种情绪障碍,属阴性症状。     

图形辨别的负荷实验研究

本实验用IBM PC/XT计算机对30名青年人和9名中年人进行图形辨别负荷实验。结果表明:(1)同时呈现的图形数量(任务困难度)、允许辨别的时间(时间忙碌程度)和年龄都是影响被试业绩的因素。(2)在需辨别的图形数较多且有辨别速度要求的任务中,不宜选用中年人。(3)通过实验求出青年人图形辨别经验公式Y=De~(B/X),D(N)=183.1441-2.3206N 0.0249N~2,B(N)=-2.0379-0.1427N 0.0008N~2。据此公式可求出在此情境下,对一定数量的图形(N),在一定时间限定内(X)的图形正确辨别率(Y)。     

新生儿视觉分辨能力的研究

本研究的目的是用习惯化方法探讨新生儿视觉辨别能力的发展水平。一个由176名新生儿组成的样本在北京友谊医院随机取得。被试年龄在出生8分钟至13天之间。所有被试都是正常、健康的、处于觉醒状态的新生儿。实验材料是8张图片,其图案为:灰圆、红圆、黑色环形图、正常人脸、怪脸及3张黑白相间的栅条图形。这些图形随机配对组成10对,以作对比。实验结果表明:从出生起,新生儿就能对不同图案的图形进行视觉辨别;新生儿在一定程度上发展起颜色分辨的能力;两个图形,只在一个维度上相异时,较容易被新生儿辨别,新生儿的视觉分辨能力与其性别无显著相关。     

幼儿在辨别过程中图形维度显著性的研究

采用Triad Classification法和等级图形模式研究了4～6岁幼儿在辨别过程中图形维度显著性效应。实验1让幼儿进行自由辨别任务,发现颜色显著性强于形状,局部特征的显著性强于整体特征;随被试年龄增长,整体特征和颜色的显著性逐渐增强;对维度显著性等级模式的信息加工比对整体局部特征等级模式的加工反应时长。实验2进行按指定标准来辨别的任务,发现仍然出现图形维度显著性效应。这些结果说明图形维度显著性效应可能是自动发生的,可能比整体局部特征的认知加工更复杂。     

一例额颞叶病人的次序性记忆测查

通过对一名左侧额颞胶质瘤术后病人的神经心理学检查和实验，着重探讨了次序性记忆和应用题解算技能的关系。结果发现：（１）动作的次序性记忆存在；（２）数字和无意义图形的次序性记忆有显著障碍；（３）解算复杂应用题的能力基本正常，其中包括次序性应用题。这表明了复杂的计算能与次序性记忆可能没有直接关联。     

5~6岁自闭症儿童与正常儿童的辨别反转学习研究

采用条件性辨别反转范式,考察自闭症儿童与正常儿童的反转灵活性。44名5~6岁儿童（24名自闭症儿童,20名正常儿童）参加了辨别反转学习。结果显示：⑴在习得阶段,两类儿童都能辨别两个不同的条件性刺激;⑵在晚期反转阶段,正常儿童在晚期反转阶段升高了对新的条件性厌恶刺激的主观预期值,辨别了新的条件性刺激,而自闭症儿童在晚期反转阶段对新的条件性厌恶刺激的主观预期值没有显著性变化,无法辨别新的条件性刺激。研究结果表明,5~6岁自闭症儿童反转灵活性存在缺陷。     

3-6岁儿童颜色及图形视觉辨认实验研究

本研究对120名学前儿童(3—6岁)进行了12种颜色和12种图形的辨认实验。实验刺激用速示器分三种速度(0.01秒、0.05秒、0.1秒)呈现。结果表明:呈现速度对辨认正确率有着明显的影响。3—6岁儿童对颜色和图形的辨认能力均随年龄增长而逐步提高。学前儿童对颜色的辨别,在三种呈现速度条件下,均以对黄、红、绿三色的辨认正确率为最高;对图形的辨认在不同呈现速度条件下出现优势与劣势图形之分。优势图形正确辨认百分比较高,而劣势图形则较低,这种优劣势图形的产生可能与图形的空间结构特性及进行言语“句子化”编码的难易有着密切关系。     

简释被“法轮功”曲解、篡改的佛教名相

李洪志的“法轮功”所宣扬的理论如同痴人说梦,实在不值一驳,但由于他的歪理邪说在社会上流播很广,大有混淆视听的作用,对人们正信正解佛法构成障碍,作为佛教徒,我觉得有必要做一番辨别澄清的工作。名者实之宾,名正方能言顺,用佛教名相的原义来对治曲解篡改的邪说...     

中央线索化对听觉障碍人群辨别任务返回抑制的影响

选取一组先天聋被试和与之匹配的听力正常被试,采用线索提示范式考察中央线索化对听觉障碍被试在辨别任务中基于位置返回抑制的影响。实验结果发现,在有中央线索化的任务实验中,听力正常和听觉障碍被试都出现了返回抑制,但是听觉障碍被试消失得比听力正常被试早。无中央线索化的辨别任务实验中,听力正常被试组仅在SOA=650ms时,听觉障碍被试没有发现返回抑制现象。结果表明听觉障碍被试辨别任务的返回抑制更易受中央线索化条件的影响,听障被试的空间注意调节机制更具策略性和有效性。     

大脑两半球的协同活动:右半球切除十四年后某些高级机能的观察

本文介绍了一癫痫病人切除右半球14年后大脑工作的情况。神经心理学检查表明:病人在非语言形式如线条、抽象图形的感知、认知和空间关系上遭到一定程度的破坏,但对颜色、音乐、具体人物和环境的认知和空间关系上没有明显障碍。左半球代偿了右半球部分功能,病人能胜任一般工作,并愉快地过着正常生活。     

Eye-Hand Coordination in Aging and in Parkinson’s Disease

Aiming movements to defined target positions were performed as fast and as accurately as possible by younger and older subjects and by patients in the early stages of Parkinson's disease (PD). Movement time and accuracy were tested in two conditions: with and without a centre cue. Older subjects exhibited slower movement time relative to the younger subjects only when the centre cue was present suggesting inefficient feedback processing. The performance of patients with PD was found to be as precise as that of older subjects. The movements of PD subjects, however, were slower in both conditions. Finally, the performance of subjects improved over trials. The data suggest that there is no difference in the nature of the control processes used by older and early-stage PD subjects, but that there is a reduction in the speed of these processes in PD.     

Motor sequence learning performance in Parkinson's disease patients depends on the stage of disease

It is still unclear, whether patients with Parkinson's disease (PD) are impaired in the incidental learning of different motor sequences in short succession, although such a deficit might greatly impact their daily life. The aim of this study was thus to clarify the relation between disease parameters of PD and incidental motor learning of two different sequences in short succession. Results revealed that the PD patients were able to acquire two sequences in short succession but needed more time than healthy subjects. However, both the severity of axial manifestations, as assessed on a subsection of the Unified Parkinson's Disease Rating Scale III (UPDRS III) and the Hoehn and Yahr score, and the levodopa-equivalent dose (LED) were negatively correlated with the sequence learning performance. These findings indicate that, although PD patients are able to learn two sequences in short succession, they need more time and their overall sequence learning performance is strongly correlated with the stage of disease.     

Executive function in Parkinson’s disease: contributions of the dorsal frontostriatal pathways to action and motivation

Disruption of the dorsal frontostriatal pathways in Parkinson’s disease (PD) is associated with impairments in motivation, as well as in executive function. The goal of this study was to investigate whether these impairments are related and, if so, whether the disruption of frontostriatal pathways compromises the ability to process the motivational aspects of feedback in such tasks. In Experiment 1, informative feedback improved the performance of young, healthy participants in a task-switching paradigm. This task-switching paradigm was then used in Experiment 2 to test whether feedback would improve the performance of 17 PD patients and age-matched controls. The PD group benefitted from feedback to the same degree as control participants; however, depression scores on the Beck Depression Inventory were significantly related to feedback usage, especially when response selection demands were high. Regardless of feedback, PD patients were more impaired when response demands were high than in an equally difficult condition with low action demands. These results suggest that response selection is a core impairment of insufficient dopamine to the dorsal frontal striatal pathways.     

Sentence comprehension in Parkinson's disease: the role of attention and memory.

Sentence comprehension is a complex process involving at least attentional, memory, grammatical, and semantic components. We report three experiments designed to evaluate the impairments underlying sentence comprehension difficulties in nondemented patients with Parkinson's disease (PD). In the first experiment, we asked patients to answer simple questions about sentences which varied in terms of grammatical complexity and semantic constraint. We found that PD patients are significantly compromised in their ability to perform this task. Their difficulties became more prominent as grammatical complexity increased, but they were significantly assisted by semantic constraints that limited possible interpretations of a sentence. Analyses of individual patient profiles revealed heterogeneous performance across the group of PD patients and somewhat inconsistent performance for patients across testing sessions. In the second experiment, we tested the possibility that patients' heterogeneous performance on the sentence comprehension task is due to an impairment in memory or attention, cognitive domains known to be compromised in some PD patients. Although PD patients and control subjects differed on one memory measure, there were no significant correlations between attention and memory performance and the results of the sentence comprehension task. In the final experiment, we manipulated the sentences used in the first experiment in a fashion that stressed the need for memory and attention in a sentence. The results indicated that PD patients are significantly compromised in their ability to attend to certain critical grammatical features of a sentence. A regression analysis identified specific grammatical, semantic, and attentional mechanisms as significant contributors to PD patients' overall sentence comprehension, accounting for over 97% of the variance in their performance. We conclude that there are multiple sources of cognitive difficulty underlying PD patients' sentence comprehension impairment.     

Assessment of visual-spatial deficits in patients with Parkinson's disease and closed head injuries using virtual environments.

Cognitive spatial deficits have been reliably reported in patients with Closed Head Injury (CHI), though in patients with Parkinson's disease (PD) the phenomenon is disputed. CHI and non-demented PD patients were tested using a Judgement of Line Orientation Test, and two spatial tests using virtual environments (VEs). Performance on the Line Orientation and one VE test was worse in the CHI group than controls, but PD patients showed no apparent spatial deficits. However, performance on the second VE test (virtual tray of objects task) did reveal a deficit, both CHI and PD groups being significantly impaired. The data illustrate that particular spatial deficits can be differentiated using appropriate VE-based tasks, and that non-demented PD patients show a paradigm-specific visual-spatial impairment.     

Targeted training of the decision rule benefits rule-guided behavior in Parkinson’s disease

The impact of Parkinson’s disease (PD) on rule-guided behavior has received considerable attention in cognitive neuroscience. The majority of research has used PD as a model of dysfunction in frontostriatal networks, but very few attempts have been made to investigate the possibility of adapting common experimental techniques in an effort to identify the conditions that are most likely to facilitate successful performance. The present study investigated a targeted training paradigm designed to facilitate rule learning and application using rule-based categorization as a model task. Participants received targeted training in which there was no selective-attention demand (i.e., stimuli varied along a single, relevant dimension) or nontargeted training in which there was selective-attention demand (i.e., stimuli varied along a relevant dimension as well as an irrelevant dimension). Following training, all participants were tested on a rule-based task with selective-attention demand. During the test phase, PD patients who received targeted training performed similarly to control participants and outperformed patients who did not receive targeted training. As a preliminary test of the generalizability of the benefit of targeted training, a subset of the PD patients were tested on the Wisconsin card sorting task (WCST). PD patients who received targeted training outperformed PD patients who did not receive targeted training on several WCST performance measures. These data further characterize the contribution of frontostriatal circuitry to rule-guided behavior. Importantly, these data also suggest that PD patient impairment, on selective-attention-demanding tasks of rule-guided behavior, is not inevitable and highlight the potential benefit of targeted training.     

Parkinson's disease is associated with goal setting deficits during task switching

Ten Parkinson's Disease (PD) patients and 10 control participants were tested using a task-switching paradigm in which there was a random task sequence, and the task was cued in every trial. Five PD patients showed a unique error profile. Their performance approximated guessing when accuracy was dependent on correct task identification, and was nearly perfect when accuracy did not depend on correct task identification or in conditions without task switching. Nonetheless, PD patients showed normal task-rule implementation, evidenced by their preparation-related reduction in the reaction-time task-switching cost. The results indicate that, without redundant task information, some PD patients have a specific goal setting deficit, reflected in a difficulty determining which task is currently relevant.     

The effects of clinical motor variables and medication dosage on working memory in Parkinson’s disease

In this study, we investigate the interrelationship between clinical variables and working memory (WM) in Parkinson’s disease (PD). Specifically, the aim of the study was to investigate the relationship between disease duration, dopaminergic medication dosage, and motor disability (UPDRS score) with WM in individuals with PD. Accordingly, we recruited three groups of subjects: unmedicated PD patients, medicated PD patients, and healthy controls. All subjects were tested on three WM tasks: short-delay WM, long-delay WM, and the n-back task. Further, PD encompasses a spectrum that can be classified either into akinesia/rigidity or resting tremor as the predominant motor presentation of the disease. In addition to studying medication effects, we tested WM performance in tremor-dominant and akinesia-dominant patients. We further correlated WM performance with disease duration and medication dosage. We found no difference between medicated and unmedicated patients in the short-delay WM task, but medicated patients outperformed unmedicated patients in the long-delay WM and n-back tasks. Interestingly, we also found that akinesia-dominant patients were more impaired than tremor-dominant patients at various WM measures, which is in agreement with prior studies of the relationship between akinesia symptom and basal ganglia dysfunction. Moreover, the results show that disease duration inversely correlates with more demanding WM tasks (long-delay WM and n-back tasks), but medication dosage positively correlates with demanding WM performance. In sum, our results show that WM impairment in PD patients depend on cognitive domain (simple vs. demanding WM task), subtype of PD patients (tremor- vs. akinesia-dominant), as well as disease duration and medication dosage. Our results have implications for the interrelationship between motor and cognitive processes in PD, and for understanding the role of cognitive training in treating motor symptoms in PD.     

Laterality of repetitive finger movement performance and clinical features of Parkinson’s disease

Impairments in acoustically cued repetitive finger movement often emerge at rates near to and above 2 Hz in persons with Parkinson’s Disease (PD) in which some patients move faster (hastening) and others move slower (bradykinetic). The clinical features impacting this differential performance of repetitive finger movement remain unknown. The purpose of this study was to compare repetitive finger movement performance between the more and less affected side, and the difference in clinical ratings among performance groups. Forty-one participants diagnosed with idiopathic PD completed an acoustically cued repetitive finger movement task while “on” medication. Eighteen participants moved faster, 10 moved slower, and 13 were able to maintain the appropriate rate at rates above 2 Hz. Clinical measures of laterality, disease severity, and the UPDRS were obtained. There were no significant differences between the more and less affected sides regardless of performance group. Comparison of disease severity, tremor, and rigidity among performance groups revealed no significant differences. Comparison of posture and postural instability scores revealed that the participants that demonstrated hastening had worse posture and postural instability scores. Consideration of movement rate during the clinical evaluation of repetitive finger movement may provide additional insight into varying disease features in persons with PD.