Left Hemisphere Lesions Research Articles

Reliability and Validity of the Comprehensive Limb and Oral Apraxia Test: Standardization and Clinical Application in Korean Patients With Stroke.

Objective To develop and standardize the Limb and Oral Apraxia Test (LOAT) for Korean patients and investigate its reliability, validity, and clinical usefulness for patients with stroke.MethodsWe developed the LOAT according to a cognitive neuropsychological model of limb and oral praxis. The test included meaningless, intransitive, transitive, and oral praxis composed of 72 items (56 items on limb praxis and 16 items on oral praxis; maximum score 216). We standardized the LOAT in a nationwide sample of 324 healthy adults. Intra-rater and inter-rater reliability and concurrent validity tests were performed in patients with stroke. We prospectively applied the LOAT in 80 patients and analyzed the incidence of apraxia. We also compared the clinical characteristics between the apraxia and non-apraxia groups.ResultsThe internal consistency was high (Cronbach’s alpha=0.952). The inter-rater and intra-rater reliability and concurrent validity were also high (r=0.924–0.992, 0.961–0.999, and 0.830, respectively; p<0.001). The mean total, limb, and oral scores were not significantly different according to age and education (p>0.05). Among the 80 patients with stroke, 19 (23.8%) had limb apraxia and 21 (26.3%) had oral apraxia. Left hemispheric lesions and aphasia were significantly more frequently observed in the limb/oral apraxia group than in the non-apraxia group (p<0.001).ConclusionThe LOAT is a newly developed comprehensive test for limb and oral apraxia for Korean patients with stroke. It has high internal consistency, reliability, and validity and is a useful apraxia test for patients with stroke.

Hemispheric tumor location and the impact on health-related quality of life, symptomatology, and functional performance outcomes in patients with glioma: an exploratory cross-sectional study

Purpose To inform high-quality rehabilitation services, this study investigates if patients with glioma located in the right- or left-hemisphere present with different health-related quality of life, symptomatology, and functional performance in the early disease state. Material and methods Between 2013 and 2017, 81 adult patients were assessed during the first week of chemo-radiation, following resection. Patients were stratified into two groups depending on a right- or left-hemispheric lesion. Independent t-tests analyzed potential differences regarding health-related quality of life, symptomatology, and functional performance. Results Forty-five patients (56%) had a tumor located in the right hemisphere, whereas 36 patients (44%) had a tumor in the left hemisphere. Except for more patients with tumors in the left hemisphere having their tumor located in eloquent brain areas, the groups were well matched. No group differences were found in health-related quality of life. Group differences were found in communication deficits (Δ-10.9, 95%CI −19.1; −2.3, p = 0.01), which were more frequent in patients with left-sided lesions, and of headaches (Δ13.9, 95%CI 1.8; 25.9, p = 0.02), which were more frequent in patients with right-hemispheric lesions, who also had significantly greater difficulties with process-skills when performing everyday life tasks (Δ-0.3, 95%CI −0.5; −0.1, p < 0.01). Also, weak evidence suggests that patients with Glioblastoma Multiforme located in the right hemisphere are more affected by fatigue compared to their left-hemispheric comparisons (Δ14.6, 95%CI 0.19; 29.0, p < 0.05). Conclusions The hemispheric location of a glial-cell brain tumor has no consequence for health-related quality of life at the beginning of chemo-radiation treatments. However, findings of tumor-location dependent conditions of communication, headache, patients’ ability to perform executive functions, and fatigue should be considered in rehabilitation situations when designing an intervention to potentially improve executive functions and relieve the symptoms. Implications for rehabilitation It is unclear if laterality impact glioma patients health-related quality of life and functional performance, which might implicate differentiated rehabilitation interventions. The hemispheric location of a glial-cell brain tumor has no consequence for the health-related quality of life at the beginning of chemo-radiation, following surgery. Tumor-location dependent conditions of communication, headache, fatigue, and patients’ ability to perform executive functions should be considered when designing an intervention to improve executive functions and symptom-relieve. In rehabilitation interventions, tumor laterality is not a factor that needs to be considered before recommending aerobic training to improve the functional capacity of patients with glioma.

Phantom touch: How to unmask sensory unawareness after stroke

Comprehending the nature of tactile disorders following brain damage is crucial to understand how the brain constructs sensory awareness. Stroke patients may be unaware of being touched on the affected hand if, simultaneously, they are touched on the unaffected hand (i.e., tactile extinction). More rarely, they feel touches on the two hands, when they are solely touched on the unaffected hand (i.e., synchiria). Using a novel assessment tool, we investigated whether in stroke patients with apparent intact tactile awareness on standard evaluation, tactile extinction might be possibly masked by phantom (synchiric) sensations (i.e., elicited by ipsilesional stimulation) arising exclusively during Double Simultaneous Stimulation (DSS). Patients with right (n = 17) and left (n = 8) hemisphere lesions and age-matched healthy controls (n = 13) were tested with the Tactile Quadrant Stimulation test, consisting in delivering unilateral or bilateral touches to one of four quadrants, identified on the participants' hands. In DSS trials, stimuli were applied to asymmetric quadrants. Participants reported the side(s) and then pointed to the site(s) of stimulation. We found that, with the exception of one patient who showed tactile extinction, about 50% of patients with overall intact tactile perception on classical evaluation, although reporting two stimuli in DSS, failed in pointing to the correct contralesional stimulated site. They reported the felt sensation in positions that corresponded to the ipsilesional stimulated sites. Thus apparent detections of contralesional touches in DSS were accounted for by ‘phantom’ sensations of ipsilesional stimulation that masked unawareness of contralesional touches when classic assessment was applied. Preliminary lesion analyses indicate that the symptom was associated with damage to structures often affected in tactile extinction. These findings, while unveiling important underestimation of the patients' neurological condition, provide a framework for investigating bihemispheric contributions to altered tactile perception following stroke.

Transient naming deficits associated with insular lesions in a patient with encephalitis

ABSTRACTWe describe a patient with acute herpes simplex encephalitis with left-hemispheric hippocampal, parahippocampal and insular lesions. Although prototypic language areas were unaffected, the patient suffered from an inability to name objects or animals displayed on pictures. This deficit was transient and gradually disappeared 8 weeks after the initial diagnosis. Our findings are in line with a previous report showing similar deficits in a patient with a comparable lesion pattern and support the hypothesis that left insular lesions can produce severe naming deficits. Using FDG-PET we ruled out that functional deactivation in classical language areas account for the observed naming deficits.

Paradoxical recovery of L2 in a bilingual aphasic person: addressing issues on causative factors and accent

ABSTRACT Background The pattern of language deficits and recovery in bilingual aphasia is variable. An uncommon and intriguing pattern of evolution is referred to as paradoxical recovery (PR) or switching, which refers to the resurgence of a language which a person with aphasia had barely used or not used at all before the brain injury in conjunction with a limited ability to speak in L1. There is no agreement about which causative factors are the most influential for PR and a detailed analysis on the status of accent in L2 has not been explored so far. Aims In this study, we analysed verbal production in a successive bilingual illiterate right-handed woman (MASS) who, after suffering a traumatic brain injury (TBI) in the left temporo-frontal region, developed non-fluent aphasia in L1 (Spanish) together with a PR of a low proficient and not used L2 (Catalan). Methods & Procedure A qualitative linguistic analysis of bilingual aphasia and a vowel acoustic analysis of verbal production were conducted in MASS. A perceptual test to examine her accent by native speakers was also performed. Outcomes & Results PR in MASS was manifested by the release of a fluent anomic speech in L2 together with a marked reduction of speech production in L1. The circumstances in which L2 was learned included late acquisition, mostly by passive exposure, and low proficiency. Moreover, MASS displayed a negative attitude towards using L2 which may explain why phonetic analysis revealed a vowel system with values that were close to L1 (Spanish). In the perceptual test, bilingual judges identified the items presented as corresponding to a native Spanish-speaking woman. Conclusions The circumstances of L2 acquisition in MASS may have contributed to its PR and the non-use of this language in everyday life could explain the persistence of native Spanish accent when she spoke using L2. The coexistence of a left hemisphere lesion, late acquisition, passive exposure, and low proficiency of L2 may have favoured the release of right hemisphere activity in linguistic control, thus accounting for PR and persistence of L1 accent.

Language and cognitive outcomes after childhood stroke: Theoretical implications for hemispheric specialization

The purpose of this study was to investigate language and cognitive outcomes following severe childhood stroke, and the role of age at stroke according to lesion lateralization.We retrospectively included children consecutively admitted to a physical medicine and rehabilitation department between 1992 and 2015 following childhood stroke (age at stroke 1 month to15 years). Data collection included demographic and clinical information, results of cognitive assessments on the Wechsler Intelligence scales, detailed language assessments by speech and language therapists, and long-term academic outcome.Overall, 184 children (52% boys; mean age at assessment = 8.5 years, range .7–15.4 years) were hospitalized following ischemic (n = 79) or hemorrhagic (n = 105) stroke. After a median time since stroke of 4 months (n = 135), mean Full-Scale, Verbal, and Performance Intellectual Quotient (FSIQ, VIQ and PIQ) were 85 (SD = 19), 93 (SD = 22), and 85 (SD = 20), respectively. In language tests (n = 130) assessing lexical and syntactic expression and comprehension, 26%–53% of the children exhibited impairments (scores <2SD). After a median follow-up of 40 months, only 27% of the children were following a normal curriculum without adaptations or delay, and 27% were attending special education programs. School situation was strongly associated with language and FSIQ scores. Language and verbal IQ scores were significantly lower (p < .01) among patients with lesions in the left hemisphere as opposed to the right. After a left hemisphere lesion, language skills were not associated with age at stroke, but for right hemisphere lesions, language was more impaired among children who were younger at stroke onset. PIQ tended to correlate positively with age at stroke in left hemisphere lesions (poorer PIQ in early lesions) and negatively for right hemisphere lesions (poorer PIQ in late lesions).These findings, discussed in the light of the brain vulnerability and plasticity hypotheses, are in favor of a developmental view of hemispheric specialization.

Differences between the Influence of Observing One's Own Movements and Those of Others in Patients with Stroke.

We aimed to investigate differences between the influence of observing one's own actions and those of others in patients with stroke with hemiplegia. Thirty-four patients with stroke who had experienced a right or left hemispheric lesion (RHL: n = 17; LHL: n = 17) participated in this study. Participants viewed video clips (0.5× speed) of their own stepping movements (SO) as well as those of others (OO). After viewing the video clips, participants were asked to evaluate the vividness of the mental image of the observed stepping movement using a five-point scale, in accordance with that utilized in the Kinesthetic and Visual Imagery Questionnaire (KVIQ). We also examined changes in imagery and execution times following action observation. When all patients were considered, there were no significant differences between SO and OO conditions. However, in the RHL subgroup, KVIQ kinesthetic subscore and changes in imagery and execution times were greater in the OO condition than in the SO condition. In the LHL subgroup, changes in imagery times were greater in the SO condition than in the OO condition. These findings indicated that viewing the movements of others led to more vivid imagery and alteration in performance in patients with right-sided stroke, when compared to viewing one's own movements. Therefore, the present study suggests that clinicians should consider the side of the damaged hemisphere when implementing action observation therapy for patients with stroke.

Attention Deficits in Stroke Patients: The Role of Lesion Characteristics, Time from Stroke, and Concomitant Neuropsychological Deficits.

Attention impairments are frequent in stroke patients with important consequences on the rehabilitation outcomes and quality of life. The aim of the study was to perform a comprehensive assessment of selective and intensive attention processes in a large population of brain-damaged patients, evaluating the influence of the side and site of the brain lesion, the time from stroke, and the concomitant presence of aphasia or neglect. We assessed 204 patients with a first unilateral brain lesion and 42 healthy individuals with three subtests of the Test of Attentional Performance (TAP): Alertness, Go-No Go, and Divided Attention. 44.4% of patients had an impairment in both intensive and selective aspects of attention, 5.6% had deficits only in the intensive component, and 31.8% had deficits only in selective tasks. More than 80% of the patients fell below the cut-off point on at least one task. Patients with a right hemispheric lesion (RHL) were more impaired than patients with a left hemispheric lesion (LHL) especially in tonic and phasic alertness. Patients with total anterior infarcts (TACI) presented the worst profile compared to other stroke subtypes, with a difference between total and lacunar subtypes in the Alertness test, independent of the presence of warning. Patients in the chronic phase had shorter RTs than acute patients only in the Alertness test. In patients with LHL, the presence of aphasia was associated with a greater deficit in selective attention. In patients with RHL, the presence of unilateral neglect was associated with impaired alertness and selective attention. Attention deficits are common after a unilateral first stroke. In keeping with the hierarchical organization of attention functions, results confirm the important role of the right hemisphere for the intensive components of attention, also highlighting the involvement of left hemisphere functioning for the selective aspects, possibly indicating a role of its linguistic functions.

Disorders of fine motor skills after a stroke: the processes of neuroplasticity and sensorimotor integration

Background. Impairment of fine motor skills in the hand is one of the most frequent causes of the persistent loss of professional skills, social maladjustment, and the impossibility of self-care in patients after a stroke, which ultimately leads to a significant reduction in the quality of their life. The article discusses the features of the fine motor skills’ impairment in the hand in patients after a stroke, in the context of a lateralized hemispheric lesion.&#x0D; Methods. We have studied 26 patients after a primary ischemic stroke in the pool of middle cerebral artery of the right (n=12) or left (n=14) brain hemisphere. The average age of patients was 55.7±7.3 years. Patients with a right-sided ischemic stroke were comparable to those with a left-sided stroke in their age, disease duration, size of the lesion and the gender ratio.&#x0D; Results. All the patients after an ischemic stroke had motor impairment in the form of a hemiparesis of a mild or moderate degree.&#x0D; Discussion. We suggest the existence of differentiated mechanisms for the development of fine and highly coordinated voluntary movements in the hand of patients after an ischemic stroke, depending on the lateralization of the supratentorial lesion: diffuse deficit of the afferent support in a right-sided ischemic stroke vs. bilateral efferent deficit for a left hemisphere lesion.&#x0D; Conclusion. The obtained data on the differentiated mechanisms for the development of fine and highly coordinated voluntary movements in the hand of patients after an ischemic stroke warrant the necessity of a further, more targeted research on those disorders in the post-stroke period, on order to optimize the existing rehabilitation approaches and improve the functional potential and quality of life of such patients.

Prosodic Stress: Acoustic Changes in Spoken English in Patients with Left and Right Hemisphere Lesions (P3.1-012)

Prosodic Stress: Acoustic Changes in Spoken English in Patients with Left and Right Hemisphere Lesions (P3.1-012)

The Performance of the Korean Montreal Protocol for Evaluation of Communication in the Stroke Patients with Right vs. Left Hemispheric groups: A Qualitative and Quantitative Analysis

대뇌 손상 부위에 따라 의사소통장애 양상이 다르기 때문에 언어평가도구에 포함되는 문항들도 달라져야 한다. 그러나 국내 실어증 평가도구는 좌반구 뇌졸중 환자를 위주로 개발된 도구이므로 우뇌 손상 환자의 인지-의사소통장애 유무와 양상을 파악하는 데에는 제약이 있다. 본 연구는 우뇌 손상 환자를 위한 의사소통평가도구를 좌뇌 및 우뇌 손상 뇌졸중 환자 각 25명씩 총 50명에게 적용한 후, 좌·우뇌 뇌졸중에 따른 하위검사 영역별 수행력 차이를 알아보았다. 그 결과, 우뇌 손상군이 ‘대화적 담화’, ‘구어유창성(비제한적/음소/의미)’, ‘언어적 운율-따라말하기’, ‘감정적 운율-따라말하기’, ‘감정적 운율-산출’ 하위검사에서 좌뇌 손상군보다 유의하게 낮은 수행력을 보였다. ‘은유’, ‘감정적 운율’, ‘화행’ 및 ‘대화적 담화’를 이해하는 과제나 ‘어휘 판단’ 과제에서는 두 집단 간 유의한 차이가 없었으나, 과제 반응 양상에서 질적인 차이를 보였다. 우뇌 손상군의 특이성에 초점을 두고 개발된 의사소통평가도구이지만 일부 하위검사 영역은 실어증 검사의 실어증 지수와도 유의한 상관성을 보여 우뇌 관장 영역으로 알려져 있던 일부 의사소통 능력의 처리과정에 좌뇌도 함께 관여하고 있음을 알 수 있었다. 이를 기초로 추후 인지-의사소통장애를 보이는 우뇌 손상 환자를 대상으로 한 적극적인 평가와 중재를 기대해 볼 수 있을 것이다.The items included in language assessment must be able to differentiate between different lesion sites. The aphasia battery of Korea is a limited in identifying the existence and characteristics of cognitive-communication disorders in patients with right hemisphere dysfunction (RHD). In this study, the communication assessment for RHD was administered to 25 stroke patients with left hemisphere dysfunction (LHD) and 25 patients with RHD. The differences in performance in each subtest according to left and right hemispheric lesions were examined. The RHD group exhibited significantly worse performance than that of the LHD group in the 5 domains. However, there were no significant differences in comprehension task between the two groups, they showed qualitative differences in response type. Communication assessment was developed focusing on specificity for RHD, however, some subtests showed significant correlation with the aphasia battery. Based on this, active evaluation and intervention can be expected for patients with RHD who show cognitive-communication disorders.

Positive Correlation between Left Hemisphere Lesion and Erectile Dysfunction in Post-Stroke Patients.

BACKGROUND:Stroke is a serious health condition and the leading cause of disability, including erectile dysfunction (ED). The mechanisms and factors that predict ED in stroke are not fully elucidated. Several studies have shown a relationship between the location of the lesion in stroke with the onset of ED. The left hemispheric lesion was believed to disrupt the parasympathetic nervous system which is responsible for the regulation of erection. Stroke attack in this region therefore can be the underlying reason for ED. However, there are still contradictory findings in this area, and very few studies attempted to look at this problem, particularly among Asian male.AIM:We would like to evaluate the association between left hemisphere lesion after ischemic stroke and the subsequent risk of developing ED.METHODS:The study was conducted in the neurology polyclinic of Sanglah and Wangaya Hospital from February to August 2013. Subjects are all post-stroke patients who visited the neurology polyclinic of Sanglah and Wangaya Hospital that met inclusion and exclusion criteria.RESULTS:There is a significant positive correlation (p < 0.05) between left hemisphere lesions and ED in stroke patients with a correlation coefficient (r) = 0.361 which means weak correlation and p = 0.032.CONCLUSION:Left hemisphere lesions positively correlated with ED in stroke patients. Further longitudinal research is needed to see whether left hemisphere lesion in post-stroke patients is a risk factor for ED.

Activation of Bilateral Secondary Somatosensory Cortex With Right Hand Touch Stimulation: A Meta-Analysis of Functional Neuroimaging Studies.

Background: Brain regions involved in processing somatosensory information have been well documented through lesion, post-mortem, animal, and more recently, structural and functional neuroimaging studies. Functional neuroimaging studies characterize brain activation related to somatosensory processing; yet a meta-analysis synthesis of these findings is currently lacking and in-depth knowledge of the regions involved in somatosensory-related tasks may also be confounded by motor influences.Objectives: Our Activation Likelihood Estimate (ALE) meta-analysis sought to quantify brain regions that are involved in the tactile processing of the right (RH) and left hands (LH) separately, with the exclusion of motor related activity.Methods: The majority of studies (n = 41) measured activation associated with RH tactile stimulation. RH activation studies were grouped into those which conducted whole-brain analyses (n = 29) and those which examined specific regions of interest (ROI; n = 12). Few studies examined LH activation, though all were whole-brain studies (N = 7).Results: Meta-analysis of brain activation associated with RH tactile stimulation (whole-brain studies) revealed large clusters of activation in the left primary somatosensory cortex (S1) and bilaterally in the secondary somatosensory cortex (S2; including parietal operculum) and supramarginal gyrus (SMG), as well as the left anterior cingulate. Comparison between findings from RH whole-brain and ROI studies revealed activation as expected, but restricted primarily to S1 and S2 regions. Further, preliminary analyses of LH stimulation studies only, revealed two small clusters within the right S1 and S2 regions, likely limited due to the small number of studies. Contrast analyses revealed the one area of overlap for RH and LH, was right secondary somatosensory region.Conclusions: Findings from the whole-brain meta-analysis of right hand tactile stimulation emphasize the importance of taking into consideration bilateral activation, particularly in secondary somatosensory cortex. Further, the right parietal operculum/S2 region was commonly activated for right and left hand tactile stimulation, suggesting a lateralized pattern of somatosensory activation in right secondary somatosensory region. Implications for further research and for possible differences in right and left hemispheric stroke lesions are discussed.

A computationally implemented mechanistic account of post-stroke aphasia recovery

A computationally implemented mechanistic account of post-stroke aphasia recovery

Memory monitoring and memory control in chronic stroke patients Dissociated processes.

ABSTRACT.Memory problems are common in stroke patients, although little is known about how accurately chronic stroke patients can monitor and control memory processes.Objective:The performance of memory and metamemory in stroke patients and healthy controls were investigated, as well as dissociation between performances.Methods:10 adults with right hemisphere lesion (mean [M] age=53.2 [SD=9.7]), 10 with left hemisphere lesion (M age=60.4 [SD=6.6]) and 20 healthy participants (M age=56.5 [SD=9.3] with no neurological disease, matched for sex, age and years of education participated in a multiple-case design study. Participants completed a metamemory experimental paradigm, as well as immediate and delayed word recall and recognition tasks.Results:Data indicated that 10 out of the 20 patients presented significantly lower scores compared to controls, two of which had global deficits (functional association). Functional dissociations between memory monitoring (judgments of learning, JOL), control (allocation of study time) and capacity (cued-recall task) among patients were found for eight cases, suggesting these processes are independent.Conclusion:These findings reveal stroke patients may have specific metamemory impairment and can contribute to the understanding of cognitive models of metamemory processing.

Study of Factor Associated with Post Stroke Depression in the Teaching Hospital of Fann (Dakar-Senegal)

Introduction: Strokes are becoming more common in Africa, they are often accompanied by depressive symptoms, hence the need to investigate the factors associated with it for better management and prevention. Methodology: We conducted a prospective cross-sectional study amongst patients hospitalized with stroke at the Neurology/Neuroscience Clinic of the FANN UNHC (Dakar) in 2016. After a clinical diagnosis, patients are subjected to socio-demographic questionnaire and were administered with modified Rankin and MADRS scores. Results: Among the patients, 33.7% had Post-Stroke Depression, most were aged 50 to 70 years, male and married. History of stroke and depression was strongly associated with Post-Stroke Depression, while functional or cognitive impairment caused by stroke contributed to the development of Post Stroke depression. The type of ischemic or haemorrhagic stroke did not appear to affect the occurrence of the Post-Stroke Depression, but Post-Stroke Depression was more frequent in subjects with a left hemispheric lesion 47.8% (p < 0.05). Discussion: The occurrence of a Post-Stroke Depression is a factor of poor prognosis, early diagnosis and holistic care lead to improved quality of life.

Neural correlates of speech error monitoring and awareness

Neural correlates of speech error monitoring and awareness

Development of a Worldwide Screening Test for Communicative Disorders Poststroke for International Comparisons

Development of a Worldwide Screening Test for Communicative Disorders Poststroke for International Comparisons

Bolus Transition During Oropharyngeal Swallowing after Unilateral Cortical Stroke

Purpose Bolus transition during swallowing represents neuromuscular coordination between oropharyngeal structures and bolus movement. The purpose of this study was to examine the difference between stroke patients with left and right hemisphere lesion in terms of oral and pharyngeal transitions using oral transit time (OTT), pharyngeal transit time (PTT), and duration of upper esophageal sphincter opening (DUESO) during swallowing. Methods Thirty-four unilateral cortical stroke patients were divided into two groups depending on the hemispheric site of the lesion. Means and standard deviations of OTT, PTT, and DUESO were measured on 2 mL and 5 mL of thin liquid swallows from videofluoroscopic swallowing examinations (VFSEs). Statistical comparison was performed by repeated measurements of analysis of variance (ANOVA). Significance level was set at <0.025. Results In OTT, PTT, and DUESO, there was no significant difference between left and right hemispheric stroke groups. There was a significant bolus volume effect on OTT and DUESO. Conclusions The site of the lesion may not affect the transition of bolus during oropharyngeal swallowing. Clinicians should not only examine physiological swallowing disorders of individual patients regardless of hemispheric site of the lesion, but also investigate various volumes during VFSEs in order to find the proper diet recommendation. Keywords: Bolus transition; Oral stage; Pharyngeal stage; Swallowing; Unilateral stroke

Brain networks' functional connectivity separates aphasic deficits in stroke.

To investigate whether different language deficits are distinguished by the relative strengths of their association with the functional connectivity (FC) at rest of the language network (LN) and cingulo-opercular network (CON) after aphasic stroke. In a group of patients with acute stroke and left-hemisphere damage, we identified 3 distinct, yet correlated, clusters of deficits including comprehension/lexical semantic, grapheme-phoneme knowledge, and verbal executive functions. We computed partial correlations in which the contributions of a behavioral cluster and network FC of no interest were statistically regressed out. We observed a double dissociation such that impairment of grapheme-phoneme knowledge was more associated with lower FC of the LN within the left hemisphere than lower FC of the CON, whereas verbal executive deficits were more related to lower FC of the CON than the LN in the left hemisphere. Furthermore, the specific association between language deficits and FC was independent of the amount of structural damage to the LN and CON. These findings indicate that after a left-hemisphere lesion, the type of language impairment is related to the abnormal pattern of correlated activity in different networks. Accordingly, they extend the concept of a neuropsychological double dissociation from structural damage to functional network abnormalities. Finally, current results strongly argue in favor of the behavioral specificity of intrinsic brain activity after focal structural damage.