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1.
卒中部位及局部脑血流量对智力的影响   总被引:3,自引:1,他引:2  
用长谷川智力测定量表法测定了189例卒中患者的智力,分析了病变部位、脑萎缩及局部脑血流量(rCBF)对智力的影响.其中69例患者长谷川分数低于21.5分.当病变位于左半球时,属痴呆或可疑痴呆者达42.9%;而病变位于右半球时,仅23.1%属痴呆及可疑痴呆.rCBF与长谷川分数之间的相关分析显示:左额、右颞及左顶叶的rCBF与长谷川分数呈极显著正相关.提示左半球在智力活动中起主导作用.脑萎缩亦是影响智力的因素.  相似文献   

2.
A specific set of syndromes, based on different intrahemispheric lesion locations, has not yet been described in patients with right hemisphere lesions. To explore whether statistically derived clusters could give clues to a syndrome structure, neuropsychological data from a sample of 106 patients with right hemisphere stroke were studied. CT data were available for 58 of the patients. Based on factor analysis of eight test and four ratings variables, six variables were chosen for a cluster analysis. A structure of 13 clusters was considered statistically valid. Combining clusters with parallel test profiles into main cluster classes, five right hemisphere syndromes proved clinically valid: an above average syndrome ( n =46), denial perseverance (frontal) syndrome ( n =14). a depressed mood syndrome ( n = 14), a focal RH syndrome ( n =18) and a global RH syndrome ( n =9). It is suggested that syndromes are related to intrahemispheric location of the lesion, such as the extent of anterior and posterior damage.  相似文献   

3.
Aphasia is a common symptom after left hemispheric stroke. Neuroimaging techniques over the last 10–15 years have described two general trends: Patients with small left hemisphere strokes tend to recruit perilesional areas, while patients with large left hemisphere lesions recruit mainly homotopic regions in the right hemisphere. Non-invasive brain stimulation techniques such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) have been employed to facilitate recovery by stimulating lesional and contralesional regions. The majority of these brain stimulation studies have attempted to block homotopic regions in the right posterior inferior frontal gyrus (IFG) to affect a presumed disinhibited right IFG (triangular portion). Other studies have used anodal or excitatory tDCS to stimulate the contralesional (right) fronto-temporal region or parts of the intact left IFG and perilesional regions to improve speech-motor output. It remains unclear whether the interhemispheric disinhibition model, which is the basis for motor cortex stimulation studies, also applies to the language system. Future studies could address a number of issues, including: the effect of lesion location on current density distribution, timing of the intervention with regard to stroke onset, whether brain stimulation should be combined with behavioral therapy, and whether multiple brain sites should be stimulated. A better understanding of the predictors of recovery from natural outcome studies would also help to inform study design, and the selection of clinically meaningful outcome measures in future studies.  相似文献   

4.
Patients with either a left- or a right-hemisphere stroke lesion scored higher in tasks of word-picture matching and of nonverbal shape matching when information was presented tachistoscopically (120 msec) to the visual field (VF) projecting to their undamaged hemisphere. Left-hemisphere stroke patients (n = 13) were dissociated from right-hemisphere stroke patients (n = 15) by low word recognition from memory and by low right VF but nearly normal left VF accuracy in word-picture matching or shape matching; the former appeared to rely upon processing of word meaning by the right hemisphere. In contrast, right-stroke patients had higher right than left VF scores in both tasks, and their discrimination of nonverbal shapes via the right VF was not different from that of controls (n = 15). Preferred processing by the VF projecting to the undamaged hemisphere appeared as a shift in perceptual asymmetry but may indicate, in support of a "direct access" model, that each hemisphere responds more or less efficiently to word and to nonverbal shape discriminations.  相似文献   

5.
A comprehensive test battery was devised to study the effects of right hemisphere lesions on the speech and language of “nonaphasic” dextrals. Data were thus obtained for 62 subjects, 20 of them neurologically healthy and 42 with a focal right hemisphere lesion resulting from a cerebro-vascular accident. A preliminary global analysis of these data is reported. Anomalies were observed in 33 brain-damaged subjects. Although discreet in all cases, these anomalies were shown to have various degrees of severity. Given the population submitted to this study, the subject most likely to show such anomalies was defined, genetically, as a right-handed adult with a family history of ambidextrality or left-handedness and, socially, as one with a relatively limited education. The implications of these findings are discussed together with the problem of the anatomo-clinical correlations of language disorders resulting from right hemisphere lesions in “nonaphasic” dextrals.  相似文献   

6.
Unilateral visuospatial neglect is now widely acknowledged to be a highly heterogeneous condition: The overt manifestations of visual neglect can vary as a function of task, spatial domain, and mode of response (at least). Double dissociations (sometimes of the strong form) have already been reported between most of the components of what was originally thought to be a relatively stable construct within the visual modality. Nonetheless, throughout successive fractionations of neglect, reported cases of bidirectional task-specific neglect after unilateral brain damage are rare. We now report two such cases. After right hemisphere stroke, the first patient reliably showed severe left neglect on cancellation but right neglect on line bisection. After left hemisphere stroke, the second case showed right neglect on cancellation but left neglect on line bisection. Extensive investigation of case 1 confirmed our previous conjecture that the crucial distinction between these tasks lies in the presence or the absence of an overt target. In contrast to cancellation, line bisection demands the internal computation of the location of the “target” (the midpoint), followed by executing a motor response toward the precise location of that “imaginary” midpoint. The relative attentional and premotor contributions of the intact and damaged hemispheres to these forms of bidirectional neglect are also assessed.  相似文献   

7.
The frequency of various types of unilateral spatial neglect and associated areas of neural dysfunction after left hemisphere stroke are not well characterized. Unilateral spatial neglect (USN) in distinct spatial reference frames have been identified after acute right, but not left hemisphere stroke. We studied 47 consecutive right handed patients within 48h of left hemisphere stroke to determine the frequency and distribution of types of right USN using cognitive testing and MRI imaging. The distribution of USN types was different from the previously reported distribution following acute right hemisphere stroke. In this left hemisphere stroke population, allocentric neglect was more frequent than egocentric neglect.  相似文献   

8.
This study describes the linguistic and neuropsychological findings in three right-handed patients with crossed conduction aphasia. Despite the location of the lesion in the right hemisphere, all patients displayed a combination of linguistic deficits typically found in conduction aphasia following analogous damage to the left hemisphere. Associated cognitive deficits varied across the three patients. In addition, all cases showed deficits classically attributed to non-dominant hemisphere damage (visuoperceptual deficits and reduced figural memory). As a result, lesion-behaviour relationships in our study sample indicate both dominant and non-dominant qualities of the right hemisphere.  相似文献   

9.
Patients with left hemisphere (LH) or right hemisphere (RH) brain injury due to stroke were tested on a speeded, color discrimination task in which two factors were manipulated: (1) the categorical relationship between the target and the distracters and (2) the visual field in which the target was presented. Similar to controls, the RH patients were faster in detecting targets in the right visual field when the target and distracters had different color names compared to when their names were the same. This effect was absent in the LH patients, consistent with the hypothesis that injury to the left hemisphere handicaps the automatic activation of lexical codes. Moreover, the LH patients showed a reversed effect, such that the advantage of different target-distracter names was now evident for targets in the left visual field. This reversal may suggest a reorganization of the color lexicon in the right hemisphere following left hemisphere brain injury and/or the unmasking of a heightened right hemisphere sensitivity to color categories.  相似文献   

10.
Data from lesion studies suggest that the ability to perceive speech sounds, as measured by auditory comprehension tasks, is supported by temporal lobe systems in both the left and right hemisphere. For example, patients with left temporal lobe damage and auditory comprehension deficits (i.e., Wernicke's aphasics), nonetheless comprehend isolated words better than one would expect if their speech perception system had been largely destroyed (70-80% accuracy). Further, when comprehension fails in such patients their errors are more often semantically-based, than-phonemically based. The question addressed by the present study is whether this ability of the right hemisphere to process speech sounds is a result of plastic reorganization following chronic left hemisphere damage, or whether the ability exists in undamaged language systems. We sought to test these possibilities by studying auditory comprehension in acute left versus right hemisphere deactivation during Wada procedures. A series of 20 patients undergoing clinically indicated Wada procedures were asked to listen to an auditorily presented stimulus word, and then point to its matching picture on a card that contained the target picture, a semantic foil, a phonemic foil, and an unrelated foil. This task was performed under three conditions, baseline, during left carotid injection of sodium amytal, and during right carotid injection of sodium amytal. Overall, left hemisphere injection led to a significantly higher error rate than right hemisphere injection. However, consistent with lesion work, the majority (75%) of these errors were semantic in nature. These findings suggest that auditory comprehension deficits are predominantly semantic in nature, even following acute left hemisphere disruption. This, in turn, supports the hypothesis that the right hemisphere is capable of speech sound processing in the intact brain.  相似文献   

11.
Nass RD  Trauner D 《CNS spectrums》2004,9(6):420-434
Despite a congenital stroke, overall intelligence at school age is generally within the normal range. Language acquisition problems are more prominent when children are younger (<5 years of age) than when they are older. They are present after both right and left lesions, but appear to have different features. They are less apparent than in the child with a developmental language disorder. Acquired aphasia in childhood results in subtle and often persisting deficits. Children with congenital strokes are at risk for behavioral and psychiatric problems. Those with congenital right hemisphere strokes appear to be more difficult infants, but there is no clear side of lesion effect in older children. Children with congenital right hemisphere strokes have more prominent spatial difficulties than their left lesion counterparts. Evaluating both the process and the product highlights this. Increasing the difficulty of the task often brings out deficits in the right lesion group even when they seemingly recovered.  相似文献   

12.
Functional imaging studies indicate that the left hemisphere mediates verbal working memory, while the right hemisphere mediates both verbal and spatial working memory. We evaluated acute stroke patients with working memory tests and imaging to identify whether unilateral dysfunction causes deficits in spatial and/or verbal working memory deficits. While left cortical stroke patients had verbal working memory impairments (p<0.003), right cortical stroke patients had both verbal p<0.007) and spatial working memory (p<0.03) impairments, confirming functional imaging results. Patients with transient ischemic stroke and patients with non-cortical stroke did not have significant deficits in working memory in either modality.  相似文献   

13.
We examined the effect of localized brain lesions on processing of the basic speech acts (BSAs) of question, assertion, request, and command. Both left and right cerebral damage produced significant deficits relative to normal controls, and left brain damaged patients performed worse than patients with right-sided lesions. This finding argues against the common conjecture that the right hemisphere of most right-handers plays a dominant role in natural language pragmatics. In right-hemisphere damaged patients, there was no correlation between location and extent of lesion in perisylvian cortex and performance on BSAs. By contrast, processing of the different BSAs by left hemisphere-damaged patients was strongly affected by perisylvian lesion location, with each BSA showing a distinct pattern of localization. This finding raises the possibility that the classical left perisylvian localization of language functions, as measured by clinical aphasia batteries, partly reflects the localization of the BSAs required to perform these functions.  相似文献   

14.
15.
Crossover by Line Length and Spatial Location   总被引:2,自引:0,他引:2  
It is well known that line length has a systematic influence on line bisection error in neglect. Most patients with neglect misbisect long lines on the same side of true center as their brain lesion but then cross over on short lines, misbisecting them on the opposite side (i.e., crossover by line length). What is less recognized is that the spatial location of lines relative to the viewer can similarly induce a crossover effect when one considers line bisection error scores that have been averaged across individual line lengths. Patients with right hemisphere injury and neglect classically make averaged line bisection errors that fall right of true center on lines located either at midline or to the left of the viewer; however, we observed that the averaged line bisection error can fall left of true center when lines are located to the right of the viewer (i.e., crossover by spatial location). We hypothesized that crossover by both line length and spatial location stem from systematic errors in magnitude estimation, i.e., perceived line length. We tested predictions based on this hypothesis by examining how the crossover effect by line length is altered by the spatial location of lines along a horizontal axis relative to the viewer. Participants included patients with unilateral lesions of the right and left cerebral hemispheres and age-appropriate normal subjects. All groups demonstrated a crossover effect by line length at the midline location but the effect was altered by placing lines to the right and left of the viewer. In particular, patients with right hemisphere injury and neglect crossed-over across a broader range of line lengths when the lines were located to the right of the viewer rather than at either midline or left of the viewer. It is proposed that mental representations of stimulus magnitude are altered in neglect, in addition to mental representations of space, and that traditional accounts of neglect can be enhanced by including the psychophysical concept of magnitude estimation.  相似文献   

16.
Apraxia usually follows a left hemisphere lesion in right-handers with left hemisphere speech representation. Apraxia following a right hemisphere lesion in left-handers is rare, however, and not well documented in the literature. Two left-handed patients are described in whom apraxia and aphasia followed a right hemisphere lesion. Both the apraxic and the aphasic deficits improved but were still demonstrable 6 weeks following the infarct. The data are consistent with those for right-handers with left hemisphere lesions in suggesting some overlap of anatomical structures for the control of speech and praxis.  相似文献   

17.
In 2002, the Forensic Psychiatric Hospital in Berlin started a pilot project for combined treatment of sex-offenders with anti-androgenic LH-RH agonists and psychotherapy. On the basis of experience-based knowledge transfer and with almost six years of practical experience, this article reports results of this new approach of combined psychotherapy and drug treatment from medical and psychological viewpoints. First, a short history and general information about the combined treatment are provided. Secondly, its effects on patients’ sexual self-perception, personality disorders and aspects of prognosis are explored. Thirdly, a medical therapy scheme, possible side effects, as well as issues of patients’ rights and approvals are discussed.  相似文献   

18.
A 52-year-old man with atypical cerebral dominance (left-handed for writing but mixed handedness for other tasks) suffered an extensive right hemisphere stroke, resulting in a combination of deficits that has not been previously reported. There were profound visual constructive and visual perceptual disturbances and a spatial agraphia, which were consistent with a nondominant hemisphere lesion. There was also a severe apraxic agraphia, which is typically associated with a dominant hemisphere lesion, but no other signs of dominant hemisphere dysfunction such as linguistic disturbance or limb-motor apraxia were present. This case serves to highlight the functional and anatomical relationship between handwriting and other forms of praxis; the various sources of error in letter formation; the need to be specific in labeling and describing agraphias ; and the role of a detailed analysis of writing errors in delineating the neuropsychological processes involved in handwriting.  相似文献   

19.
This article describes a model of comprehensive psychotherapy planning for difficult patients, especially patients with borderline personality disorders and psychotic disorders. Its aim is to develop a psychotherapeutically orientated approach to treatment corresponding to the individual needs of the patient and the people closest to them (e.g. family).Central elements of the planning process are diagnostic/therapeutical family meetings in which psychoanalytic and systemic conceptualisations are applied together. The main features of this context oriented model development are described and illustrated by case studies.The article also presents first results of an analysis of the therapy plannings and discusses the questions arising.  相似文献   

20.
The vast majority of healthy individuals are left hemisphere dominant for language; however, individuals with left hemisphere epilepsy have a higher likelihood of atypical language organization. The cerebral organization of language in epilepsy has been studied with invasive procedures such as Wada testing and electrical cortical stimulation mapping (ESM), and more recently, with noninvasive neuroimaging techniques such as functional magnetic resonance imaging (fMRI). Investigators have used these techniques to explore the influence of unique clinical features inherent in epilepsy that might contribute to the reorganization of language, such as location of seizure onset, age of seizure onset, and extent of interictal epileptiform activity. In this paper, we review the contribution of these and other clinical variables to the lateralization and localization of language in epilepsy, and how these patient-related variables affect the results from these three different, yet complementary methodologies. Unlike the abrupt language changes that occur following acute brain injury with disruption of established language circuits, converging evidence suggests that the chronic nature of epileptic activity can result in a developmental shift of language from the left to the right hemisphere or re-routing of language pathways from traditional to non-traditional areas within the dominant left hemisphere. Clinical variables have been shown to contribute to cerebral language reorganization in the setting of chronic seizure disorders, yet such factors have not been reliable predictors of altered language networks in individual patients, underscoring the need for language lateralization and localization procedures when definitive identification of language cortex is necessary for clinical care.  相似文献   

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