精神分裂症患者正反序工作记忆的脑磁图研究

目的:通过脑磁图影像学方法研究精神分裂症患者工作记忆受损情况.方法:分别对12例精神分裂症患者和10名正常人正反序记忆时同时采集脑磁图信号,与磁共振解剖像叠加形成磁源性成像,进行脑区活动分析.结果:正序记忆时患者右额上回激活较正常人明显增多(P<0.05),简单记忆任务时,就动员了较多的脑部资源,随着任务难度增大,额叶...     

Effectiveness of melodic intonation therapy in a case of aphasia following right hemisphere stroke

Background: The use of Melodic Intonation Therapy (MIT) in the clinical setting is suggested to be based on several criteria; however, some persons with aphasia not meeting these criteria may still benefit from this approach.

Aims: The purpose of this research was to explore the effectiveness of utilising MIT to improve expressive language in a person with global aphasia following right hemisphere stroke.

Methods & Procedures: A participant with global aphasia following right hemisphere haemorrhagic stroke completed a 7-week treatment programme utilising MIT. Sessions were held 5 days a week, for two and a half hours per day. Non-linguistic cognitive activities (COG) were also utilised briefly in each session as a break (BRK) from MIT. The Aphasia Diagnostic Profiles (ADP), American Speech-Language-Hearing Association-Functional Assessment of Communication Skills and the Stroke and Aphasia Quality of Life Scale-39 were administered pre- and post-treatment to assess for the treatment-related change.

Outcomes & Results: The participant responded well to MIT, completing the elementary level in 25 sessions and progressing through the intermediate level until the end of the treatment period at session 30. Performance on the ADP suggested decreased aphasia severity characterised by improved auditory comprehension, repetition, average phrase length and elicited gestures. Functional communication was slightly improved, whereas quality of life did not change. It was reported by the spouse, caregiver and clinician that the participant began using several novel phrases in appropriate context over the course of the treatment.

Conclusions: The MIT may be a valid treatment of global aphasia following right hemisphere stroke, providing more options to practising clinicians working with this population. It is likely that the criteria ruling out those with impaired auditory comprehension and those with right hemisphere lesions, regardless of lesion location, are too restrictive. Most likely, good and poor candidates for MIT can better be identified using intrahemispheric lesion location information, rather than interhemispheric.     

3D left hyperschematia after right brain damage

ABSTRACT

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves the motor symptoms of Parkinson’s disease (PD). The STN may represent an important relay station not only in the motor but also the associative cortico-striato-thalamocortical pathway. Therefore, STN stimulation may alter cognitive functions, such as working memory (WM). We examined cortical effects of STN-DBS on WM in early PD patients using functional near-infrared spectroscopy. The effects of dopaminergic medication on WM were also examined. Lateral frontal activity during WM maintenance was greater when patients were taking dopaminergic medication. STN-DBS led to a trend-level worsening of WM performance, accompanied by increased lateral frontal activity during WM maintenance. These findings suggest that STN-DBS in PD might lead to functional modifications of the basal ganglia-thalamocortical pathway during WM maintenance.     

Construct validity and reliability of working memory tasks for people with aphasia

Background: Although several studies have examined working memory in people with aphasia, there is little information about the psychometric properties of tasks used to measure working memory in this population.

Aims: The aims of this study were (1) to examine the construct validity, internal consistency, and test-retest reliability of several working memory tasks and (2) to determine which tasks were feasible to use with people with a wide range of aphasia severities.

Methods & Procedures: In experiment one, non-brain-damaged adults (n = 47) completed a set of working memory tasks that were designed for use with people with aphasia. The tasks included 1-back, 2-back, listening span and forward and backward versions of picture span and square span. Construct validity was assessed by correlating performance on the new tasks with a composite score based on three well-established working memory tasks with known psychometric properties. Ten older adults completed the testing battery twice to measure test-retest reliability. Internal consistency was estimated using split-half reliability. In experiment two, people with aphasia (n = 12) completed the new working memory tasks.

Outcomes & Results: The picture span tasks demonstrated acceptable test-retest reliability, internal consistency, and construct validity. Controls showed ceiling effects on 1-back and people with aphasia showed floor effects on listening span. Both the square span tasks and n-back showed poor internal consistency for people with aphasia and age-matched controls.

Conclusions: A composite score based on the forward and backward versions of picture span provides a measure of verbal working memory with acceptable construct validity, internal consistency and test-retest reliability and can be completed by non-brain-damaged adults and people with aphasia.     

Validity of an eye-tracking method to index working memory in people with and without aphasia

Background: Working memory (WM) is essential to auditory comprehension; thus understanding of the nature of WM is vital to research and clinical practice to support people with aphasia. A key challenge in assessing WM in people with aphasia is related to the myriad deficits prevalent in aphasia, including deficits in attention, hearing, vision, speech, and motor control of the limbs. Eye-tracking methods augur well for developing alternative WM tasks and measures in that they enable researchers to address many of the potential confounds inherent in tasks traditionally used to study WM. Additionally, eye-tracking tasks allow investigation of trade-off patterns between storage and processing in complex span tasks, and provide on-line response measures.

Aims: The goal of the study was to establish concurrent and discriminative validity of a novel eye movement WM task in individuals with and without aphasia. Additionally we aimed to explore the relationship between WM and general language measures, and determine whether trade-off between storage and processing is captured via eye-tracking measures.

Methods & Procedures: Participants with (n?=?28) and without (n?=?32) aphasia completed a novel eye movement WM task. This task, incorporating natural response requirements, was designed to circumvent potential confounds due to concomitant speech, motor, and attention deficits. The task consisted of a verbal processing component intermixed with presentation of colours and symbols for later recall. Performance on this task was indexed solely via eye movements. Additionally, participants completed a modified listening span task that served to establish concurrent validity of the eye-tracking WM task.

Outcomes & Results: Performance measures of the novel eye movement WM task demonstrated concurrent validity with another established measure of WM capacity: the modified listening span task. Performance on the eye-tracking task discriminated effectively between participants with and without aphasia. No consistent relationship was observed between WM scores and Western Aphasia Battery aphasia quotient and subtest scores for people with aphasia. Additionally, eye-tracking measures yielded no trade-off between processing and storage for either group of participants.

Conclusions: Results support the feasibility and validity of employing a novel eye-tracking method to index WM capacity in participants with and without aphasia. Further research is required to determine the nature of the relationship between WM, as indexed through this method, and specific aspects of language impairments in aphasia.     

Forward and backward digit span difficulties in children with specific learning disorder

This study examined performance in the forward and backward digit span task of the Wechsler Intelligence Scale for Children–Fourth Edition (WISC–IV) in a large group of children with specific learning disorder (SLD) as compared with a group of typically developing children matched for age and sex. Our results further support the hypothesis that the intellectual difficulties of children with SLD involve working memory in the forward digit span task to a greater extent than in the backward digit span task. The correlation of the two spans with a General Ability Index (GAI) was similar in SLD, and smaller in magnitude than in typically developing children. Despite a GAI within normal range, children with SLD had difficulty with both digit span tasks, but more so for forward span. This pattern was similar for different SLD profiles with clinical diagnoses of dyslexia and mixed disorder, but the impairments were more severe in the latter. Age differences were also investigated, demonstrating larger span impairment in older children with SLD than in younger.     

The production of linguistic prosodic structures in subjects with right hemisphere damage

This study examined the right hemisphere contribution to the production of linguistic prosody where acoustic features of prosodic structures in different linguistic contexts were examined accompanied by perceptual judgements. When control and right hemisphere damaged (RHD) subjects were asked to produce lexical stress differences (Experiment 1), prosodic boundaries to denote syntactic constituents (Experiment 2), and questions and statements (Experiment 3) conveyed through prosody, both groups were similar in producing the duration, F0 and amplitude acoustic cues within prosodic structures to convey different linguistic meanings. Listeners were able to perceive the meanings of the productions of both groups in Experiments 1 and 3, but had greater difficulty perceiving the productions of the RHD group in Experiment 2. These findings, which suggest that the right hemisphere has a limited role in the production of linguistic prosody, are discussed in relation to perceptual theories of prosody.     

Performance of younger and older adults in lateralised right and left hemisphere asymmetry tasks supports the HAROLD model

The population of industrialised societies has increased tremendously over the last century, raising the question of how an enhanced age affects cognition. The relevance of two models of healthy ageing are contrasted in the present study that both target the functioning of the two cerebral hemispheres. The right hemi-ageing model (RHAM) assumes that functions of the right hemisphere decline before those of the left hemisphere. The Hemispheric Asymmetry Reduction in Older Adults (HAROLD) model suggests that the contralateral hemisphere supports the normally superior hemisphere in a given task resulting in a reduced hemispheric asymmetry overall. In a mixed design 20 younger and 20 older adults performed both a task assessing a left (lateralised lexical decisions) and a right (sex decisions on chimeric faces) hemisphere advantage. Results indicated that lateralised performance in both tasks was attenuated in older as compared to younger adults, in particular in men. These observations support the HAROLD model. Future studies should investigate whether this reduced functional hemispheric asymmetry in older age results from compensatory processes or from a process of de-differentiation.     

Inference in right hemisphere damaged individuals' comprehension: The role of sustained attention

The ability to make inferences for the purposes of comprehension is considered an important factor in pragmatic ability. In this experimental group study with stroke patients, the ability to make inferences and its associations with sustained attention and verbal working memory were explored. A group of 14 left‐hemisphere‐damaged individuals had more difficulty with tasks requiring the ability to revise inferences than a matched control group. Their results on those tasks tended to be associated with verbal working memory capacity. A group of 14 right‐hemisphere‐damaged (RHD) individuals also had problems in revising inferences, but their results were associated with sustained attention. In addition, the RHD subjects had problems in making inferences about characters' attitudes or motives. A lack of significant differences in results on tasks between the groups of brain damaged individuals indicate that comprehension of complex information might be impaired post stroke, irrespectively of whether the damage is to the left or right hemisphere. The results suggest that sustained attention, whilst not being a solitary sufficient factor, might somehow be involved in comprehension problems related to RHD. Implications for further research and clinical management of these sometimes subtle problems are discussed.     

Shared and distinct neurophysiological components of the digits forward and backward tasks as revealed by functional neuroimaging

The digits forward (DF) and backward (DB) tasks are widely used neuropsychological measures believed to tap overlapping systems of phonological processing and working memory. Studies of focal brain lesions have partially elucidated the brain regions essential for these tasks; however relatively little information exists on the underlying functional neuroanatomy in the intact brain. We therefore examined the shared and separate neural systems of these tasks in two positron emission tomography (PET) experiments. In Experiment 1, eight healthy participants performed verbal DF, DB, and a sensorimotor control task during measurement of regional cerebral blood flow (rCBF). DF and DB each activated frontal, parietal, and cerebellar regions as well as prominently activating medial occipital cortex. To eliminate possible visuospatial confounds, Experiment 2 replicated the first experiment in six additional healthy participants who were blindfolded during the study. No differences in activation were found between the two experimental groups. Combined data from both experiments demonstrate that DF and DB rely upon a largely overlapping functional neural system associated with working memory, most notably right dorsolateral prefrontal cortex (DLPFC) and bilateral inferior parietal lobule (IPL) as well as the anterior cingulate, a region associated with attentional effort. The degree of activation increased linearly with increasing task difficulty in DF. DB additionally recruited bilateral DLPFC, left IPL, and Broca's area. Medial occipital cortex (including higher and lower visual processing areas) was robustly activated in both DF and DB and could not be attributed to visual processing per se, suggesting a possible visual imagery strategy for these aural-verbal tasks.     

Differential processing of implicature in individuals with left and right brain damage

To evaluate the processing ability of implicature , especially indirect request and indirect refusal, the Four Scenes Test was administered to 20 left hemisphere damaged (LHD) subjects, 20 right hemisphere damaged (RHD) subjects and 15 normal control subjects. The results showed first, that the performances of the brain-damaged subjects was inferior to that of the control subjects in processing implicature; second, that indirect request understanding was easier than indirect refusal understanding in the brain-damaged subjects, and the third that indirect refusal understanding in of the left hemisphere damaged subjects was inferior to that of the right hemisphere damaged subjects. There was no group difference in indirect request understanding though the ability of brain-damaged subjects was poorer than that of the normal controls. These findings suggest that LHD and RHD subjects were not the same in implicature processing and their responses depended on the implicature's modularity (refusal and request).     

Assessing chronic stroke survivors with aphasia sheds light on prevalence of spatial neglect

Background: Stroke is a chronic disease. Standardized assessment is essential in order to determine areas for treatment. Individuals with aphasia are often excluded from research, because it is believed that their language impairments may impact their ability to provide informed consent. Thus, right spatial neglect could be under-diagnosed.

Objective: This study was developed to (1) determine the frequency of spatial neglect in chronic left-brain stroke survivors with aphasia, (2) determine the clinical utility of an aphasia-friendly consent form, and (3) determine any differences between neglect and no-neglect groups regarding activities of daily living (ADL) performance and community independence.

Methods: Forty-six people were consented at community center. Three were screen failures secondary to the exclusion criteria. A novel, aphasia-friendly consent form was developed to facilitate participation of individuals with aphasia. This enabled 93% or 40 out of the 43 recruited participants to be included in this study. The Behavioral Inattention Test-conventional and the Catherine Bergego Scale via Kessler Foundation Neglect Assessment Process (CBS via KF-NAP) were utilized to determine neglect. The Life Space Questionnaire was used to determine community mobility and independence. The Barthel Index (BI) was used for objective clarification of performance in ADL.

Results: Successful use of the consent form resulted in determination that five out of 40 (12.5%) met criteria for spatial neglect; (on the CBS via KF-NAP). The neglect group had lower scores on the Life Space, suggesting less community mobility and independence, however, it was not statistically significant (p = 0.16). Differences in BI scores were also not significant (p = .013) but the neglect group did have reduced independence.

Conclusions: This study demonstrates the need to administer functional neglect assessments in left-brain stroke and to include individuals with aphasia in research.     

脑卒中失语症和阿尔茨海默病的语义记忆损害的研究

目的分析脑卒中失语症和阿尔茨海默病的字词理解障碍的特点,探索语言在脑内的加工过程的神经机制和指导言语康复锻炼。方法采用词画匹配的方法,比较脑卒中失语症患者和阿尔茨海默病患者在呈现时间、语义相关性、字词频率、反应一致性4种条件下的字词理解的成绩。结果呈现时间作用、语义相关性作用影响失语症患者的理解成绩。字词频率是决定阿尔茨海默病患者成绩的一个主要因素。反应不一致性是失语症患者的特点,而在阿尔茨海默病患者中没有观察到反应不一致性。结论脑卒中失语症患者的字词理解障碍,是由于对已存贮的语义表象的再现受损;阿尔茨海默病患者的字词理解障碍,系由于已存贮的语义表象本身缺陷。     

Effects of working memory load on processing of sounds and meanings of words in aphasia

BACKGROUND: Language performance in aphasia can vary depending on several variables such as stimulus characteristics and task demands. This study focuses on the degree of verbal working memory (WM) load inherent in the language task and how this variable affects language performance by individuals with aphasia. AIMS: The first aim was to identify the effects of increased verbal WM load on the performance of judgments of semantic similarity (synonymy) and phonological similarity (rhyming). The second aim was to determine if any of the following abilities could modulate the verbal WM load effect: semantic or phonological access, semantic or phonological short-term memory (STM) and any of the following executive processing abilities: inhibition, verbal WM updating, and set shifting. METHOD AND PROCEDURES: Thirty-one individuals with aphasia and 11 controls participated in this study. They were administered a synonymy judgment task and a rhyming judgment task under high and low verbal WM load conditions that were compared to each other. In a second set of analyses, multiple regression was used to identify which factors (as noted above) modulated the verbal WM load effect. OUTCOME AND RESULTS: For participants with aphasia, increased verbal WM load significantly reduced accuracy of performance on synonymy and rhyming judgments. Better performance in the low verbal WM load conditions was evident even after correcting for chance. The synonymy task included concrete and abstract word triplets. When these were examined separately, the verbal WM load effect was significant for the abstract words, but not the concrete words. The same pattern was observed in the performance of the control participants. Additionally, the second set of analyses revealed that semantic STM and one executive function, inhibition ability, emerged as the strongest predictors of the verbal WM load effect in these judgment tasks for individuals with aphasia. CONCLUSIONS: The results of this study have important implications for diagnosis and treatment of aphasia. As the roles of verbal STM capacity, executive functions and verbal WM load in language processing are better understood, measurements of these variables can be incorporated into our diagnostic protocols. Moreover, if cognitive abilities such as STM and executive functions support language processing and their impairment adversely affects language function, treating them directly in the context of language tasks should translate into improved language function.     

The influence of left and right hemisphere brain damage on configural and featural processing of affective faces

The literature about the lateralization of facial emotion perception according to valence (positive, negative) is conflicting; investigating the underlying processes may shed light on why some studies show right-hemisphere dominance across valence and other studies demonstrate hemispheric differences according to valence. This is the first clinical study to examine whether the use of configural and featural cues underlies hemispheric differences in affective face perception. Right brain-damaged (RBD; n = 17), left brain-damaged (LBD; n = 17) and healthy control (HC; n = 34) participants completed an affective face discrimination task that tested configural processing using whole faces and featural processing using partial faces. No group differences in expression perception according to valence or processing strategy were found. Across emotions, the RBD group was less accurate than the HC group in discriminating whole faces, whilst the RBD and LBD groups were less accurate than HCs in discriminating partial faces. This suggests that the right hemisphere processes facial expressions from configural and featural information, whereas the left hemisphere relies more heavily on featural facial information.     

以二项迫选数字记忆测验辨别伪装智能损伤的对照分析

目的 采用二项迫选数字记忆测验辨别伪装智能损伤的患者。方法 采用二项迫选数字记忆测验方法,对交通事故所致颅脑外伤后智能鉴定患者进行测验,并对其中一部分患者进行智测前后对比。结果 ①测验总分辨别的伪装率为44．55％,与临床经验辨别的伪装率(28．18％)相比,其辨别率有提高(16．37％)。②韦氏智测前后二次的二项迫选数字记忆测验有显著差异。③按韦氏分级法IQ为35～54的患者该测验与正常人比较无显著差异,而IQ为55以上各组与正常人的比较均有显着差异。结论 二项迫选数字记忆测验是辨别伪装智能损伤的有效工具,并可指导测试者在智测前对患者进行心理疏导,以提高其智测合作程度。     

A comparison of drawing and writing on facilitating word retrieval in individuals with aphasia

ABSTRACT

Background: Drawing has long been a focus in aphasia research as a compensatory strategy for improving functional communication in individuals with aphasia, but fewer studies have addressed drawing as a facilitative tool to improve their verbal output.

Aims: The purpose of the current study was to investigate differences in naming accuracy in individuals with aphasia during a drawing versus a writing condition. Two research questions were formed to examine the role of drawing in facilitating naming: 1) Will participants perform better when naming with drawing compared to confrontation naming only or when naming with writing? and 2) Is the quality of the picture drawn related to the naming accuracy?

Methods & Procedures: Across three separate one-hour sessions, fifteen individuals with aphasia (n = 15) aged 44–81 years (M = 61.47, SD = 13.27) were evaluated using two standardized language assessments, the Western Aphasia Battery-Revised and Pyramid and Palm Tree Test, and three naming tasks designed to assess the effect of writing and drawing on naming performance. The three naming conditions consisted of confrontation naming only, naming with drawing, and naming with writing.

Outcomes & Results: A one-way, repeated measures analysis of variance (ANOVA) was computed to analyze the impact of naming conditions on the participants’ naming accuracy. The main effect of naming conditions was statistically significant, F (1, 14) = 5.87, p < 0.05, and Bonferroni correction revealed that the participants performed significantly better in the naming with drawing condition than with writing condition. In addition, no correlation between the quality of the pictures drawn and the participants’ naming performance was found which suggested that the quality of drawing did not affect the accuracy of naming.

Conclusions: When attempting to name a picture along with drawing its representation, the act of drawing may facilitate word retrieval by stimulating the semantic network associated with the word and involving the right cerebral hemisphere in the word retrieval process. Through drawing, these semantic features of the target word are more strongly activated than other related words. When the semantic features are more strongly activated, the probabilities of retrieving the target word may increase. In contrast, writing heavily relies on the left hemisphere and linguistic systems. Thus, naming when attempting to write the associated word may be a more cognitively and linguistically demanding task for individuals with aphasia.     

尼麦角林对放射性脑损伤患者脑功能重塑的临床研究

目的 探讨尼麦角林对因头颈部肿瘤采取放疗治疗致放射性脑损伤患者脑功能重塑的影响.方法 回顾性分析我院与三九脑科医院2010-01-2014-01收治的84例放射治疗致脑损伤的患者的临床资料,随机分为观察组和对照组各42例,对照组行常规康复治疗,观察组在对照组基础上加用尼麦角林.比较2组康复治疗前及康复治疗后第2周、4周相关神经功评分及治疗4周后头痛症状、MRI病灶变化分级等指标差异.结果 观察组神经功能缺损程度评分、ADL、MESSS评分改善均显著优于对照组,差异均有统计学意义(P＜0.05).观察组头痛症状分布和总有效率显著优于对照组,差异均具有统计学意义(P＜0.05),头颅MRI病灶变化显效率及总有效率均显著高于对照组,差异均有统计学意义(P＜0.05).结论 尼麦角林对于放射性脑损伤脑功能重建有积极作用,值得临床应用推广.     

The neuroanatomy of visual extinction following right hemisphere brain damage: Insights from multivariate and Bayesian lesion analyses in acute stroke

Multi-target attention, that is, the ability to attend and respond to multiple visual targets presented simultaneously on the horizontal meridian across both visual fields, is essential for everyday real-world behaviour. Given the close link between the neuropsychological deficit of extinction and attentional limits in healthy subjects, investigating the anatomy that underlies extinction is uniquely capable of providing important insights concerning the anatomy critical for normal multi-target attention. Previous studies into the brain areas critical for multi-target attention and its failure in extinction patients have, however, produced heterogeneous results. In the current study, we used multivariate and Bayesian lesion analysis approaches to investigate the anatomical substrate of visual extinction in a large sample of 108 acute right hemisphere stroke patients. The use of acute stroke patient data and multivariate/Bayesian lesion analysis approaches allowed us to address limitations associated with previous studies and so obtain a more complete picture of the functional network associated with visual extinction. Our results demonstrate that the right temporo-parietal junction (TPJ) is critically associated with visual extinction. The Bayesian lesion analysis additionally implicated the right intraparietal sulcus (IPS), in line with the results of studies in neurologically healthy participants that highlighted the IPS as the area critical for multi-target attention. Our findings resolve the seemingly conflicting previous findings, and emphasise the urgent need for further research to clarify the precise cognitive role of the right TPJ in multi-target attention and its failure in extinction patients.