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Sample records for left hemisphere stroke

  1. Apraxia and spatial inattention dissociate in left hemisphere stroke.

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    Timpert, David C; Weiss, Peter H; Vossel, Simone; Dovern, Anna; Fink, Gereon R

    2015-10-01

    Theories of lateralized cognitive functions propose a dominance of the left hemisphere for motor control and of the right hemisphere for spatial attention. Accordingly, spatial attention deficits (e.g., neglect) are more frequently observed after right-hemispheric stroke, whereas apraxia is a common consequence of left-hemispheric stroke. Clinical reports of spatial attentional deficits after left hemisphere (LH) stroke also exist, but are often neglected. By applying parallel analysis (PA) and voxel-based lesion-symptom mapping (VLSM) to data from a comprehensive neuropsychological assessment of 74 LH stroke patients, we here systematically investigate the relationship between spatial inattention and apraxia and their neural bases. PA revealed that apraxic (and language comprehension) deficits loaded on one common component, while deficits in attention tests were explained by another independent component. Statistical lesion analyses with the individual component scores showed that apraxic (and language comprehension) deficits were significantly associated with lesions of the left superior longitudinal fascicle (SLF). Data suggest that in LH stroke spatial attention deficits dissociate from apraxic (and language comprehension) deficits. These findings contribute to models of lateralised cognitive functions in the human brain. Moreover, our findings strongly suggest that LH stroke patients should be assessed systematically for spatial attention deficits so that these can be included in their rehabilitation regime. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Right hemisphere grey matter structure and language outcomes in chronic left hemisphere stroke

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    Xing, Shihui; Lacey, Elizabeth H.; Skipper-Kallal, Laura M.; Jiang, Xiong; Harris-Love, Michelle L.; Zeng, Jinsheng

    2016-01-01

    The neural mechanisms underlying recovery of language after left hemisphere stroke remain elusive. Although older evidence suggested that right hemisphere language homologues compensate for damage in left hemisphere language areas, the current prevailing theory suggests that right hemisphere engagement is ineffective or even maladaptive. Using a novel combination of support vector regression-based lesion-symptom mapping and voxel-based morphometry, we aimed to determine whether local grey matter volume in the right hemisphere independently contributes to aphasia outcomes after chronic left hemisphere stroke. Thirty-two left hemisphere stroke survivors with aphasia underwent language assessment with the Western Aphasia Battery-Revised and tests of other cognitive domains. High-resolution T1-weighted images were obtained in aphasia patients and 30 demographically matched healthy controls. Support vector regression-based multivariate lesion-symptom mapping was used to identify critical language areas in the left hemisphere and then to quantify each stroke survivor’s lesion burden in these areas. After controlling for these direct effects of the stroke on language, voxel-based morphometry was then used to determine whether local grey matter volumes in the right hemisphere explained additional variance in language outcomes. In brain areas in which grey matter volumes related to language outcomes, we then compared grey matter volumes in patients and healthy controls to assess post-stroke plasticity. Lesion–symptom mapping showed that specific left hemisphere regions related to different language abilities. After controlling for lesion burden in these areas, lesion size, and demographic factors, grey matter volumes in parts of the right temporoparietal cortex positively related to spontaneous speech, naming, and repetition scores. Examining whether domain general cognitive functions might explain these relationships, partial correlations demonstrated that grey matter

  3. Efficacy of strategy training in left hemisphere stroke patients with apraxia : A randomised clinical trial

    NARCIS (Netherlands)

    Donkervoort, M; Dekker, J; Stehmann-Saris, FC; Deelman, B. G.

    2001-01-01

    The objective of the present study was to determine in a controlled study the efficacy of strategy training in left hemisphere stroke patients with apraxia. A total of 113 left hemisphere stroke patients with apraxia were randomly assigned to two treatment groups; (1) strategy training integrated

  4. Ipsilateral deficits in 1-handed shoe tying after left or right hemisphere stroke.

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    Poole, Janet L; Sadek, Joseph; Haaland, Kathleen Y

    2009-10-01

    Poole JL, Sadek J, Haaland KY. Ipsilateral deficits in 1-handed shoe tying after left or right hemisphere stroke. To examine 1-handed shoe tying performance and whether cognitive deficits more associated with left or right hemisphere damage differentially affect it after unilateral stroke. Observational cohort comparing ipsilesional shoe tying, spatial and language skills, and limb praxis. Primary care Veterans Affairs and private medical center. Not applicable. Volunteer right-handed sample of adults with left or right hemisphere damage and healthy demographically matched adults. The number of correct trials and the total time to complete 10 trials tying a shoe using the 1-handed method. Both stroke groups had fewer correct trials and were significantly slower tying the shoe than the control group. Spatial skills predicted accuracy and speed after right hemisphere damage. After left hemisphere damage, accuracy was predicted by spatial skills and limb praxis, while speed was predicted by limb praxis only. Ipsilesional shoe tying is similarly impaired after left or right hemisphere damage, but for different reasons. Spatial deficits had a greater influence after right hemisphere damage, and limb apraxia had a greater influence after left hemisphere damage. Language deficits did not affect performance, indicating that aphasia does not preclude using this therapy approach. These results suggest that rehabilitation professionals should consider assessment of limb apraxia and ipsilesional skill training in the performance of everyday tasks.

  5. Prevalence of apraxia among patients with a first left hemisphere stroke in rehabilitation centres and nursing homes.

    OpenAIRE

    Donkervoort, M.; Dekker, J.; Ende, E. van den; Stehmann-Saris, J.C.; Deelman, B.G.

    2000-01-01

    OBJECTIVE: To investigate the prevalence of apraxia in patients with a first left hemisphere stroke. SUBJECTS: Left hemisphere stroke patients staying at an inpatient care unit of a rehabilitation centre or nursing home and receiving occupational therapy (n = 600). MEASURES: A short questionnaire on general patient characteristics and stroke-related aspects was completed by occupational therapists for every left hemisphere stroke patient they treated. A diagnosis of apraxia or nonapraxia was ...

  6. Phonotactic awareness deficit following left-hemisphere stroke

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    Maryam Ghaleh

    2015-04-01

    Likert-type scale responses were z-transformed and coded accurate for positive z-values in condition 3 and negative z-values in condition 1 trials. Accuracy was analyzed using binomial mixed effects models and z-transformed scale responses were analyzed using linear mixed effects models. For both analyses, the fixed effects of stimulus, trial number, group (patient/control, education, age, response time, phonotactic regularity (1/3, and gender were examined along with all relevant interactions. Random effects for participant and stimuli as well as random slopes were also included. Model fitting was performed in a backward-stepwise iterative fashion, followed by forward fitting of maximal random effects structure. Models were evaluated by model fitness comparisons using Akaike Information Criterion and Bayesian Information Criterion. Accuracy analysis revealed that healthy participants were significantly more accurate than patients [β = 0.47, p<0.001] in Englishness rating. Scale response analysis revealed a significant effect of phonotactic regularity [β = 1.65, p<0.0001] indicating that participants were sensitive to phonotactic regularity differences among non-words. However, the significant interaction of group and phonotactic regularity [β = -0.5, p= 0.02] further demonstrated that, compared to healthy adults, patients were less able to recognize the phonotactic regularity differences between non-words. Results suggest that left-hemisphere lesions cause impaired phonotactic processing and that the left hemisphere might be necessary for phonotactic awareness. These preliminary findings will be followed up by further analyses investigating the interactions between phonotactic processing and participants’ scores on other linguistic/cognitive tasks as well as lesion-symptom mapping.

  7. Prevalence of apraxia among patients with a first left hemisphere stroke in rehabilitation centres and nursing homes.

    Science.gov (United States)

    Donkervoort, M; Dekker, J; van den Ende, E; Stehmann-Saris, J C; Deelman, B G

    2000-04-01

    To investigate the prevalence of apraxia in patients with a first left hemisphere stroke. Left hemisphere stroke patients staying at an inpatient care unit of a rehabilitation centre or nursing home and receiving occupational therapy (n = 600). A short questionnaire on general patient characteristics and stroke-related aspects was completed by occupational therapists for every left hemisphere stroke patient they treated. A diagnosis of apraxia or nonapraxia was made in every patient, on the basis of a set of clinical criteria. The prevalence of apraxia among 492 first left hemisphere stroke patients in rehabilitation centres was 28% (96/338) and in nursing homes 37% (57/154). No relationship was found between the prevalence of apraxia and age, gender or type of stroke (haemorrhage or infarct). This study shows that approximately one-third of left hemisphere stroke patients has apraxia.

  8. Cognitive alterations in motor imagery process after left hemispheric ischemic stroke.

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    Jing Yan

    Full Text Available BACKGROUND: Motor imagery training is a promising rehabilitation strategy for stroke patients. However, few studies had focused on the neural mechanisms in time course of its cognitive process. This study investigated the cognitive alterations after left hemispheric ischemic stroke during motor imagery task. METHODOLOGY/PRINCIPAL FINDINGS: Eleven patients with ischemic stroke in left hemisphere and eleven age-matched control subjects participated in mental rotation task (MRT of hand pictures. Behavior performance, event-related potential (ERP and event-related (desynchronization (ERD/ERS in beta band were analyzed to investigate the cortical activation. We found that: (1 The response time increased with orientation angles in both groups, called "angle effect", however, stoke patients' responses were impaired with significantly longer response time and lower accuracy rate; (2 In early visual perceptual cognitive process, stroke patients showed hypo-activations in frontal and central brain areas in aspects of both P200 and ERD; (3 During mental rotation process, P300 amplitude in control subjects decreased while angle increased, called "amplitude modulation effect", which was not observed in stroke patients. Spatially, patients showed significant lateralization of P300 with activation only in contralesional (right parietal cortex while control subjects showed P300 in both parietal lobes. Stroke patients also showed an overall cortical hypo-activation of ERD during this sub-stage; (4 In the response sub-stage, control subjects showed higher ERD values with more activated cortical areas particularly in the right hemisphere while angle increased, named "angle effect", which was not observed in stroke patients. In addition, stroke patients showed significant lower ERD for affected hand (right response than that for unaffected hand. CONCLUSIONS/SIGNIFICANCE: Cortical activation was altered differently in each cognitive sub-stage of motor imagery after

  9. The course of apraxia and ADL functioning in left hemisphere stroke patients treated in rehabilitation centres and nursing homes.

    NARCIS (Netherlands)

    Donkervoort, M.; Dekker, J.; Deelman, B.

    2006-01-01

    OBJECTIVE: To study the course of apraxia and daily life functioning (ADL) in left hemisphere stroke patients with apraxia. DESIGN: Prospective cohort study. SETTING: Rehabilitation centres and nursing homes. SUBJECTS: One hundred and eight left hemisphere stroke patients with apraxia, hospitalized

  10. Prevalence of apraxia among patients with a first left hemisphere stroke in rehabilitation centres and nursing homes

    NARCIS (Netherlands)

    Donkervoort, M; Dekker, J; van den Ende, E; Stehmann-Saris, J. C.; Deelman, B. G.

    Objective: To investigate the prevalence of apraxia in patients with a first left hemisphere stroke. Subjects. Left hemisphere stroke patients staying at an inpatient care unit of a rehabilitation centre or nursing home and receiving occupational therapy (n = 600). Measures: A short questionnaire on

  11. Prevalence of apraxia among patients with a first left hemisphere stroke in rehabilitation centres and nursing homes.

    NARCIS (Netherlands)

    Donkervoort, M.; Dekker, J.; Ende, E. van den; Stehmann-Saris, J.C.; Deelman, B.G.

    2000-01-01

    OBJECTIVE: To investigate the prevalence of apraxia in patients with a first left hemisphere stroke. SUBJECTS: Left hemisphere stroke patients staying at an inpatient care unit of a rehabilitation centre or nursing home and receiving occupational therapy (n = 600). MEASURES: A short questionnaire on

  12. The course of apraxia and ADL functioning in left hemisphere stroke patients treated in rehabilitation centres and nursing homes.

    OpenAIRE

    Donkervoort, M.; Dekker, J.; Deelman, B.

    2006-01-01

    OBJECTIVE: To study the course of apraxia and daily life functioning (ADL) in left hemisphere stroke patients with apraxia. DESIGN: Prospective cohort study. SETTING: Rehabilitation centres and nursing homes. SUBJECTS: One hundred and eight left hemisphere stroke patients with apraxia, hospitalized in rehabilitation centres and nursing homes. MEASURES: ADL-observations, Barthel ADL Index, Apraxia Test, Motricity Index. RESULTS: During the study period of 20 weeks, patients showed small improv...

  13. Post-stroke acquired amusia: A comparison between right- and left-brain hemispheric damages.

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    Jafari, Zahra; Esmaili, Mahdiye; Delbari, Ahmad; Mehrpour, Masoud; Mohajerani, Majid H

    2017-01-01

    Although extensive research has been published about the emotional consequences of stroke, most studies have focused on emotional words, speech prosody, voices, or facial expressions. The emotional processing of musical excerpts following stroke has been relatively unexplored. The present study was conducted to investigate the effects of chronic stroke on the recognition of basic emotions in music. Seventy persons, including 25 normal controls (NC), 25 persons with right brain damage (RBD) from stroke, and 20 persons with left brain damage (LBD) from stroke between the ages of 31-71 years were studied. The Musical Emotional Bursts (MEB) test, which consists of a set of short musical pieces expressing basic emotional states (happiness, sadness, and fear) and neutrality, was used to test musical emotional perception. Both stroke groups were significantly poorer than normal controls for the MEB total score and its subtests (p amusia with greater severity in RBD than LBD. These results supported the "valence hypothesis" of right hemisphere dominance in processing negative emotions.

  14. Disturbances of mental image processing in post-stroke patients with left and right hemisphere damage.

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    Pachalska, M; Talar, J; Brodziak, A; MacQueen, B D

    2001-01-01

    The purpose of this article is to point out significant differences in how mental images are processed by post-stroke patients with left and right hemisphere damage. The issues involved are of theoretical importance because of the light shed on the modularity of cerebral functions, especially the imagination, and of clinical importance due to the better understanding of the underlying pathomechanism. The research involved 82 right-handed patients with a lesion in the left hemisphere (Group L), 82 right-handed patients with a lesion in the right hemisphere (Group R), and, as a control group, 82 patients with musculo-skeletal disorders not affecting the central nervous system (Group C), matched by age and sex. Image processing of complex notions was examined by using selected items from the Simple Neurolinguistic Test. In the control group, the majority of the patients responded to most of the prompts with polymodal associations of various types. In Group L, responses were dominated by isolated elements of the complex situation, while in Group R the associations were mostly verbal (lexical) and highly restricted in scope. The results indicate that the loss of LH functions interferes with the ability to assemble pieces of polymodal image information into sensible strings, while the loss of RH functions leaves strings to which little information is attached.

  15. Dissociations of action means and outcome processing in left-hemisphere stroke.

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    Kalénine, Solène; Shapiro, Allison D; Buxbaum, Laurel J

    2013-06-01

    Previous evidence suggests that distinct fronto-parietal regions may be involved in representing action kinematics (means) and action results (outcome) during action observation. However, the evidence is contradictory with respect to the precise regions that are critical for each type of representation. Additionally unknown is the degree to which ability to detect action means and outcome during observation is related to action production performance. We used a behavioral task to evaluate the ability of healthy and left-hemisphere stroke participants to detect differences between pairs of videos that dissociated object-related action means (e.g., wiping with circular or straight movement) and/or outcome (e.g., applying or removing detergent). We expected that deficits in detecting action means would be associated with spatiomotor gesture production deficits, whereas deficits in detecting action outcome would predict impairments in complex naturalistic action. We also hypothesized a posterior to anterior gradient in the regions critical for each type of representation, disproportionately affecting means and outcome encoding, respectively. Results indicated that outcome--but not means--detection predicted naturalistic action performance in stroke participants. Regression and voxel lesion-symptom mapping analyses of lesion data revealed that means--but not outcome--coding relies on the integrity of the left inferior parietal lobe, whereas no selective critical brain region could be identified for outcome detection. Thus, means and outcome representations are dissociable at both the behavioral and neuroanatomical levels. Furthermore, the data are consistent with a degree of parallelism between action perception and production tasks. Finally, they reinforce the evidence for a critical role of the left inferior parietal lobule in the representation of action means, whereas action outcome may rely on a more distributed neural circuit. Copyright © 2013 Elsevier Ltd. All

  16. Multi-tasking uncovers right spatial neglect and extinction in chronic left-hemisphere stroke patients.

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    Blini, Elvio; Romeo, Zaira; Spironelli, Chiara; Pitteri, Marco; Meneghello, Francesca; Bonato, Mario; Zorzi, Marco

    2016-11-01

    Unilateral Spatial Neglect, the most dramatic manifestation of contralesional space unawareness, is a highly heterogeneous syndrome. The presence of neglect is related to core spatially lateralized deficits, but its severity is also modulated by several domain-general factors (such as alertness or sustained attention) and by task demands. We previously showed that a computer-based dual-task paradigm exploiting both lateralized and non-lateralized factors (i.e., attentional load/multitasking) better captures this complex scenario and exacerbates deficits for the contralesional space after right hemisphere damage. Here we asked whether multitasking would reveal contralesional spatial disorders in chronic left-hemisphere damaged (LHD) stroke patients, a population in which impaired spatial processing is thought to be uncommon. Ten consecutive LHD patients with no signs of right-sided neglect at standard neuropsychological testing performed a computerized spatial monitoring task with and without concurrent secondary tasks (i.e., multitasking). Severe contralesional (right) space unawareness emerged in most patients under attentional load in both the visual and auditory modalities. Multitasking affected the detection of contralesional stimuli both when presented concurrently with an ipsilesional one (i.e., extinction for bilateral targets) and when presented in isolation (i.e., left neglect for right-sided targets). No spatial bias emerged in a control group of healthy elderly participants, who performed at ceiling, as well as in a second control group composed of patients with Mild Cognitive Impairment. We conclude that the pathological spatial asymmetry in LHD patients cannot be attributed to a global reduction of cognitive resources but it is the consequence of unilateral brain damage. Clinical and theoretical implications of the load-dependent lack of awareness for contralesional hemispace following LHD are discussed. Copyright © 2016. Published by Elsevier Ltd.

  17. Music and Stroke Rehabilitation: A Narrative Synthesis of the Music-Based Treatments used to Rehabilitate Disorders of Speech and Language following Left-Hemispheric Stroke

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    Kevin Draper

    2016-01-01

    Stroke is a leading cause of long-term disability. A stroke can damage areas of the brain associated with communication, resulting in speech and language disorders. Such disorders are frequently acquired impairments from left-hemispheric stroke. Music-based treatments have been implemented, and researched in practice, for the past thirty years; however, the number of published reports reviewing these treatments is limited. This paper uses the four elements of the narrative synthesis framework...

  18. Mental Number Line Disruption in a Right-Neglect Patient after a Left-Hemisphere Stroke

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    Pia, Lorenzo; Corazzini, Luca Latini; Folegatti, Alessia; Gindri, Patrizia; Cauda, Franco

    2009-01-01

    A right-neglect patient with focal left-hemisphere damage to the posterior superior parietal lobe was assessed for numerical knowledge and tested on the bisection of numerical intervals and visual lines. The semantic and verbal knowledge of numbers was preserved, whereas the performance in numerical tasks that strongly emphasize the visuo-spatial…

  19. The course of apraxia and ADL functioning in left hemisphere stroke patients treated in rehabilitation centres and nursing homes.

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    Donkervoort, Mireille; Dekker, Joost; Deelman, Betto

    2006-12-01

    To study the course of apraxia and daily life functioning (ADL) in left hemisphere stroke patients with apraxia. Prospective cohort study. Rehabilitation centres and nursing homes. One hundred and eight left hemisphere stroke patients with apraxia, hospitalized in rehabilitation centres and nursing homes. ADL-observations, Barthel ADL Index, Apraxia Test, Motricity Index. During the study period of 20 weeks, patients showed small improvements in apraxia (standardized mean differences of 0.19 and 0.33) and medium-sized improvements in ADL functioning (standardized mean differences from 0.37 to 0.61). About 88% of the patients were still apraxic at week 20. Less improvement in apraxia was observed in initially less severe apraxic patients. Less improvement in ADL functioning was found to be associated with more severe apraxia, a more independent initial ADL score, higher age, impaired motor functioning and longer time between stroke and first assessment. Apraxia in stroke patients is a persistent disorder, which has an adverse influence on ADL recovery.

  20. THE IMPACT OF LEFT HEMISPHERE STROKE ON FORCE CONTROL WITH FAMILIAR AND NOVEL OBJECTS: NEUROANATOMIC SUBSTRATES AND RELATIONSHIP TO APRAXIA

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    Dawson, Amanda M.; Buxbaum, Laurel J.; Duff, Susan V.

    2010-01-01

    Fingertip force scaling for lifting objects frequently occurs in anticipation of finger contact. An ongoing question concerns the types of memories that are used to inform predictive control. Object-specific information such as weight may be stored and retrieved when previously encountered objects are lifted again. Alternatively, visual size and shape cues may provide estimates of object density each time objects are encountered. We reasoned that differences in performance with familiar versus novel objects would provide support for the former possibility. Anticipatory force production with both familiar and novel objects was assessed in 6 left hemisphere stroke patients, 2 of whom exhibited deficient actions with familiar objects (ideomotor apraxia; IMA), along with 5 control subjects. In contrast to healthy controls and stroke participants without IMA, participants with IMA displayed poor anticipatory scaling with familiar objects. However, like the other groups, IMA participants learned to differentiate fingertip forces with repeated lifts of both familiar and novel objects. Finally, there was a significant correlation between damage to the inferior parietal and superior and middle temporal lobes, and impaired anticipatory control for familiar objects. These data support the hypotheses that anticipatory control during lifts of familiar objects in IMA patients are based on object-specific memories, and that the ventro-dorsal stream is involved in the long-term storage of internal models used for anticipatory scaling during object manipulation. PMID:19945445

  1. Neuroplasticity of language in left-hemisphere stroke: Evidence linking subsecond electrophysiology and structural connections

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    Piai, V.; Meyer, L.; Dronkers, N.F.; Knight, R.T.

    2017-01-01

    The understanding of neuroplasticity following stroke is predominantly based on neuroimaging measures that cannot address the subsecond neurodynamics of impaired language processing. We combined behavioral and electrophysiological measures and structural-connectivity estimates to characterize

  2. Feasibility of the cognitive assessment scale for stroke patients (CASP) vs. MMSE and MoCA in aphasic left hemispheric stroke patients.

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    Barnay, J-L; Wauquiez, G; Bonnin-Koang, H Y; Anquetil, C; Pérennou, D; Piscicelli, C; Lucas-Pineau, B; Muja, L; le Stunff, E; de Boissezon, X; Terracol, C; Rousseaux, M; Bejot, Y; Binquet, C; Antoine, D; Devilliers, H; Benaim, C

    2014-01-01

    Post-stroke aphasia makes it difficult to assess cognitive deficiencies. We thus developed the CASP, which can be administered without using language. Our objective was to compare the feasibility of the CASP, the Mini Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) in aphasic stroke patients. All aphasic patients consecutively admitted to seven French rehabilitation units during a 4-month period after a recent first left hemispheric stroke were assessed with CASP, MMSE and MoCA. We determined the proportion of patients in whom it was impossible to administer at least one item from these 3 scales, and compared their administration times. Forty-four patients were included (age 64±15, 26 males). The CASP was impossible to administer in eight of them (18%), compared with 16 for the MMSE (36%, P=0.05) and 13 for the MoCA (30%, P=0.21, NS). It was possible to administer the CASP in all of the patients with expressive aphasia, whereas the MMSE and the MoCA could not be administered. Administration times were longer for the CASP (13±4min) than for the MMSE (8±3min, P<10(-6)) and the MoCA (11±5min, P=0.23, NS). The CASP is more feasible than the MMSE and the MoCA in aphasic stroke patients. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  3. A supervised framework for lesion segmentation and automated VLSM analyses in left hemispheric stroke

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    Dorian Pustina

    2015-05-01

    Full Text Available INTRODUCTION: Voxel-based lesion-symptom mapping (VLSM is conventionally performed using skill and knowledge of experts to manually delineate brain lesions. This process requires time, and is likely to have substantial inter-rater variability. Here, we propose a supervised machine learning framework for lesion segmentation capable of learning from a single modality and existing manual segmentations in order to delineate lesions in new patients. METHODS: Data from 60 patients with chronic stroke aphasia were utilized in the study (age: 59.7±11.5yrs, post-stroke interval: 5±2.9yrs, male/female ratio: 34/26. Using a single T1 image of each subject, additional features were created that provided complementary information, such as, difference from template, tissue segmentation, brain asymmetries, gradient magnitude, and deviances of these images from 80 age and gender matched controls. These features were fed into MRV-NRF (multi-resolution voxel-wise neighborhood random forest; Tustison et al., 2014 prediction algorithm implemented in ANTsR (Avants, 2015. The algorithm incorporates information from each voxel and its surrounding neighbors from all above features, in a hierarchy of random forest predictions from low to high resolution. The validity of the framework was tested with a 6-fold cross validation (i.e., train from 50 subjects, predict 10. The process was repeated ten times, producing ten segmentations for each subject, from which the average solution was binarized. Predicted lesions were compared to manually defined lesions, and VLSM models were built on 4 language measures: repetition and comprehension subscores from the WAB (Kertesz, 1982, WAB-AQ, and PNT naming accuracy (Roach, Schwartz, Martin, Grewal, & Brecher, 1996. RESULTS: Manual and predicted lesion size showed high correlation (r=0.96. Compared to manual lesions, the predicted lesions had a dice overlap of 0.72 (±0.14 STD, a case-wise maximum distance (Hausdorff of 21mm (±16

  4. Changes in regional cerebral blood flow in the right cortex homologous to left language areas are directly affected by left hemispheric damage in aphasic stroke patients: evaluation by Tc-ECD SPECT and novel analytic software.

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    Uruma, G; Kakuda, W; Abo, M

    2010-03-01

    The objective of this study was to clarify the influence of regional cerebral blood flow (rCBF) changes in language-relevant areas of the dominant hemisphere on rCBF in each region in the non-dominant hemisphere in post-stroke aphasic patients. The study subjects were 27 aphasic patients who suffered their first symptomatic stroke in the left hemisphere. In each subject, we measured rCBF by means of 99mTc-ethylcysteinate dimmer single photon emission computed tomography (SPECT). The SPECT images were analyzed by the statistical imaging analysis programs easy Z-score Imaging System (eZIS) and voxel-based stereotactic extraction estimation (vbSEE). Segmented into Brodmann Area (BA) levels, Regions of Interest (ROIs) were set in language-relevant areas bilaterally, and changes in the relative rCBF as average negative and positive Z-values were computed fully automatically. To assess the relationship between rCBF changes of each ROIs in the left and right hemispheres, the Spearman ranked correlation analysis and stepwise multiple regression analysis were applied. Globally, a negative and asymmetric influence of rCBF changes in the language-relevant areas of the dominant hemisphere on the right hemisphere was found. The rCBF decrease in left BA22 significantly influenced the rCBF increase in right BA39, BA40, BA44 and BA45. The results suggested that the chronic increase in rCBF in the right language-relevant areas is due at least in part to reduction in the trancallosal inhibitory activity of the language-dominant left hemisphere caused by the stroke lesion itself and that these relationships are not always symmetric.

  5. Pharyngeal Swallowing Mechanics Secondary to Hemispheric Stroke.

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    May, Nelson H; Pisegna, Jessica M; Marchina, Sarah; Langmore, Susan E; Kumar, Sandeep; Pearson, William G

    2017-05-01

    Computational analysis of swallowing mechanics (CASM) is a method that utilizes multivariate shape change analysis to uncover covariant elements of pharyngeal swallowing mechanics associated with impairment using videofluoroscopic swallowing studies. The goals of this preliminary study were to (1) characterize swallowing mechanics underlying stroke-related dysphagia, (2) decipher the impact of left and right hemispheric strokes on pharyngeal swallowing mechanics, and (3) determine pharyngeal swallowing mechanics associated with penetration-aspiration status. Videofluoroscopic swallowing studies of 18 dysphagic patients with hemispheric infarcts and age- and gender-matched controls were selected from well-controlled data sets. Patient data including laterality and penetration-aspiration status were collected. Coordinates mapping muscle group action during swallowing were collected from videos. Multivariate morphometric analyses of coordinates associated with stroke, affected hemisphere, and penetration-aspiration status were performed. Pharyngeal swallowing mechanics differed significantly in the following comparisons: stroke versus controls (D = 2.19, P mechanics associated with each comparison were visualized using eigenvectors. Whereas current literature focuses on timing changes in stroke-related dysphagia, these data suggest that mechanical changes are also functionally important. Pharyngeal swallowing mechanics differed by the affected hemisphere and the penetration-aspiration status. CASM can be used to identify patient-specific swallowing impairment associated with stroke injury that could help guide rehabilitation strategies to improve swallowing outcomes. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  6. Right Hemisphere and Left Hemisphere: Pedagogical Implications for CSL Reading.

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    Mickel, Stanley L.

    Students can be taught to read Chinese more efficiently and accurately by using the specific capabilities of the right and left hemispheres of the brain. The right hemisphere is the site of image and pattern recognition, and students can be taught to use those capacities to process individual characters efficiently by watching for the element of…

  7. Right hemispatial ipsilesional neglect with chronic right hemisphere strokes.

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    Williamson, John B; Lamb, Damon G; Burtis, D Brandon; Haque, Salsabil; M Zilli, Eduardo; Kesayan, Tigran; Harciarek, Michal; Heilman, Kenneth M

    2018-05-01

    Patients who present with spatial neglect after stroke often perform normally on tests for neglect after a few weeks. Whereas tests for neglect are often performed directly in front of a patient, in their actual environments many important stimuli may be present within their left or right hemispace. The presence and severity of neglect often depends on the hemisphere injured. It is possible, in chronic stroke, for spatial judgments to be influenced by an interaction of stroke laterality and the spatial location of stimuli. The objective of this study was to learn if unilateral hemispheric chronic strokes contribute to a spatial bias with laterally presented stimuli. There were 70 participants, 62 with unilateral chronic strokes (>6 months post onset) including 35 with left hemisphere damage (LHD), 27 with right hemisphere damage (RHD), and 8 demographically similar people without history of stroke. Participants were asked to bisect 300 lines presented with distractors on the left, right, or both sides of the line, or no distractor, on a touch-screen monitor in right, center or left hemispace. There was a significant interaction between the side of the hemispheric lesion and the side of the body where these lines were presented. Specifically, in right space, patients with RHD deviated leftward in comparison to the other groups. Furthermore, there was an interaction between group and distractor induced bias. All three groups approached the left distractor, and the patients with LHD also approached the right distractor. Although spatial neglect is more severe in contralesional than ipsilesional hemispace in the period immediately following a stroke, over time patients with RHD may develop ipsilesional neglect that is more severe in ipsilesional than contralesional space. The mechanism underlying this bias is not known and may be related to attempted compensation or the development of a contralateral attentional/intentional grasp.

  8. Contralesional arm preference depends on hemisphere of damage and target location in unilateral stroke patients

    Science.gov (United States)

    Mani, Saandeep; Przybyla, Andrzej; Good, David C.; Haaland, Kathleen Y.; Sainburg, Robert L.

    2014-01-01

    Background Previous research has shown that during simulated activities of daily living right handed stroke patients use their contralesional arm more after left than right hemisphere stroke. These findings were attributed to a hand preference effect. However, these decisions about when to use the contralesional arm may be modulated by where in the work space the task is performed, a factor that could be used in physical rehabilitation to influence recovery by decreasing learned non-use. Objective To examine how target location and side of stroke influences arm selection choices for simple reaching movements. Methods Fourteen right-handed stroke patients (7 with left hemisphere damage, 7 with right hemisphere damage) with similar degree of hemiparesis (Fugl-Meyer motor score), and 16 right-handed control subjects participated in this experiment. Thirty-two targets were presented throughout the reachable horizontal plane workspace in a pseudo-random fashion, and the subjects were asked to select one hand to reach the target on each trial. Results The left hemisphere damaged group chose their contralesional arm significantly more often than the right hemisphere damaged group. Patients with right hemisphere damage also chose their left (contralesional) arm significantly less than the control group. However, these patterns of choice were most pronounced in the center of the workspace. Conclusion Both the side of hemisphere damage and workspace location played a significant role in the choice of whether to use the contralesional arm for reaching. These findings have implications for structuring rehabilitation for unilateral stroke patients. PMID:24523143

  9. Why Are the Right and Left Hemisphere Conceptual Representations Different?

    Directory of Open Access Journals (Sweden)

    Guido Gainotti

    2014-01-01

    Full Text Available The present survey develops a previous position paper, in which I suggested that the multimodal semantic impairment observed in advanced stages of semantic dementia is due to the joint disruption of pictorial and verbal representations, subtended by the right and left anterior temporal lobes, rather than to the loss of a unitary, amodal semantic system. The main goals of the present review are (a to survey a larger set of data, in order to confirm the differences in conceptual representations at the level of the right and left hemispheres, (b to examine if language-mediated information plays a greater role in left hemisphere semantic knowledge than sensory-motor information in right hemisphere conceptual knowledge, and (c to discuss the models that could explain both the differences in conceptual representations at the hemispheric level and the prevalence of the left hemisphere language-mediated semantic knowledge over the right hemisphere perceptually based conceptual representations.

  10. Auditory Processing after Early Left Hemisphere Injury: A Case Report

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    Cristina Ferraz Borges Murphy

    2017-05-01

    Full Text Available Few studies have addressed the long-term outcomes of early brain injury, especially after hemorrhagic stroke. This is the first study to report a case of acquired auditory processing disorder in a 10-year-old child who had a severe left hemorrhagic cerebral infarction at 13 months of age, compromising nearly all of the left temporal lobe. This case, therefore, is an excellent and rare opportunity to investigate the presence of neural plasticity of central auditory system in a developing brain followed severe brain damage. After assuring normal functioning of the peripheral auditory system, a series of behavioral auditory processing tests was applied in dichotic and monaural listening conditions and with verbal and non-verbal stimuli. For all verbal dichotic tasks (dichotic digits, competing words, and sentences tests, good performance on the left ear, especially for Dichotic digits test (100%, and zero performance on the right ear were observed. For monaural low-redundancy tests, the patient also exhibited good performance for auditory figure-ground and time-compressed sentences tests in the left ear. In the right ear, a very poor performance was observed, but slightly better than the same in Dichotic tasks. Impaired performance was also observed in the LiSN test in terms of spatial advantage and, for the Pitch Pattern Sequence test, the only non-verbal test applied, the patient had performance within the normal range in both ears. These results are interpreted taking into consideration the anatomical location of stroke lesion and also the influence of hemispheric specialization for language on auditory processing performance.

  11. Cortical disconnection of the ipsilesional primary motor cortex is associated with gait speed and upper extremity motor impairment in chronic left hemispheric stroke.

    Science.gov (United States)

    Peters, Denise M; Fridriksson, Julius; Stewart, Jill C; Richardson, Jessica D; Rorden, Chris; Bonilha, Leonardo; Middleton, Addie; Gleichgerrcht, Ezequiel; Fritz, Stacy L

    2018-01-01

    Advances in neuroimaging have enabled the mapping of white matter connections across the entire brain, allowing for a more thorough examination of the extent of white matter disconnection after stroke. To assess how cortical disconnection contributes to motor impairments, we examined the relationship between structural brain connectivity and upper and lower extremity motor function in individuals with chronic stroke. Forty-three participants [mean age: 59.7 (±11.2) years; time poststroke: 64.4 (±58.8) months] underwent clinical motor assessments and MRI scanning. Nonparametric correlation analyses were performed to examine the relationship between structural connectivity amid a subsection of the motor network and upper/lower extremity motor function. Standard multiple linear regression analyses were performed to examine the relationship between cortical necrosis and disconnection of three main cortical areas of motor control [primary motor cortex (M1), premotor cortex (PMC), and supplementary motor area (SMA)] and motor function. Anatomical connectivity between ipsilesional M1/SMA and the (1) cerebral peduncle, (2) thalamus, and (3) red nucleus were significantly correlated with upper and lower extremity motor performance (P ≤ 0.003). M1-M1 interhemispheric connectivity was also significantly correlated with gross manual dexterity of the affected upper extremity (P = 0.001). Regression models with M1 lesion load and M1 disconnection (adjusted for time poststroke) explained a significant amount of variance in upper extremity motor performance (R 2  = 0.36-0.46) and gait speed (R 2  = 0.46), with M1 disconnection an independent predictor of motor performance. Cortical disconnection, especially of ipsilesional M1, could significantly contribute to variability seen in locomotor and upper extremity motor function and recovery in chronic stroke. Hum Brain Mapp 39:120-132, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  12. Caffeine improves left hemisphere processing of positive words.

    Science.gov (United States)

    Kuchinke, Lars; Lux, Vanessa

    2012-01-01

    A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

  13. Caffeine improves left hemisphere processing of positive words.

    Directory of Open Access Journals (Sweden)

    Lars Kuchinke

    Full Text Available A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

  14. Imaging network level language recovery after left PCA stroke.

    Science.gov (United States)

    Sebastian, Rajani; Long, Charltien; Purcell, Jeremy J; Faria, Andreia V; Lindquist, Martin; Jarso, Samson; Race, David; Davis, Cameron; Posner, Joseph; Wright, Amy; Hillis, Argye E

    2016-05-11

    The neural mechanisms that support aphasia recovery are not yet fully understood. Our goal was to evaluate longitudinal changes in naming recovery in participants with posterior cerebral artery (PCA) stroke using a case-by-case analysis. Using task based and resting state functional magnetic resonance imaging (fMRI) and detailed language testing, we longitudinally studied the recovery of the naming network in four participants with PCA stroke with naming deficits at the acute (0 week), sub acute (3-5 weeks), and chronic time point (5-7 months) post stroke. Behavioral and imaging analyses (task related and resting state functional connectivity) were carried out to elucidate longitudinal changes in naming recovery. Behavioral and imaging analysis revealed that an improvement in naming accuracy from the acute to the chronic stage was reflected by increased connectivity within and between left and right hemisphere "language" regions. One participant who had persistent moderate naming deficit showed weak and decreasing connectivity longitudinally within and between left and right hemisphere language regions. These findings emphasize a network view of aphasia recovery, and show that the degree of inter- and intra- hemispheric balance between the language-specific regions is necessary for optimal recovery of naming, at least in participants with PCA stroke.

  15. Developmental dyslexia: dysfunction of a left hemisphere reading network

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    Fabio eRichlan

    2012-05-01

    Full Text Available This mini-review summarizes and integrates findings from recent meta-analyses and original neuroimaging studies on functional brain abnormalities in dyslexic readers. Surprisingly, there is little empirical support for the standard neuroanatomical model of developmental dyslexia, which localizes the primary phonological decoding deficit in left temporo-parietal regions. Rather, recent evidence points to a dysfunction of a left hemisphere reading network, which includes occipito-temporal, inferior frontal, and inferior parietal regions.

  16. Testing the Language of German Cerebral Palsy Patients with Right Hemispheric Language Organization after Early Left Hemispheric Damage

    Science.gov (United States)

    Schwilling, Eleonore; Krageloh-Mann, Ingeborg; Konietzko, Andreas; Winkler, Susanne; Lidzba, Karen

    2012-01-01

    Language functions are generally represented in the left cerebral hemisphere. After early (prenatally acquired or perinatally acquired) left hemispheric brain damage language functions may be salvaged by reorganization into the right hemisphere. This is different from brain lesions acquired in adulthood which normally lead to aphasia. Right…

  17. Lesion characteristics driving right-hemispheric language reorganization in congenital left-hemispheric brain damage.

    Science.gov (United States)

    Lidzba, Karen; de Haan, Bianca; Wilke, Marko; Krägeloh-Mann, Ingeborg; Staudt, Martin

    2017-10-01

    Pre- or perinatally acquired ("congenital") left-hemispheric brain lesions can be compensated for by reorganizing language into homotopic brain regions in the right hemisphere. Language comprehension may be hemispherically dissociated from language production. We investigated the lesion characteristics driving inter-hemispheric reorganization of language comprehension and language production in 19 patients (7-32years; eight females) with congenital left-hemispheric brain lesions (periventricular lesions [n=11] and middle cerebral artery infarctions [n=8]) by fMRI. 16/17 patients demonstrated reorganized language production, while 7/19 patients had reorganized language comprehension. Lesions to the insular cortex and the temporo-parietal junction (predominantly supramarginal gyrus) were significantly more common in patients in whom both, language production and comprehension were reorganized. These areas belong to the dorsal stream of the language network, participating in the auditory-motor integration of language. Our data suggest that the integrity of this stream might be crucial for a normal left-lateralized language development. Copyright © 2017. Published by Elsevier Inc.

  18. Hemispheric lateralization in an analysis of speech sounds. Left hemisphere dominance replicated in Japanese subjects.

    Science.gov (United States)

    Koyama, S; Gunji, A; Yabe, H; Oiwa, S; Akahane-Yamada, R; Kakigi, R; Näätänen, R

    2000-09-01

    Evoked magnetic responses to speech sounds [R. Näätänen, A. Lehtokoski, M. Lennes, M. Cheour, M. Huotilainen, A. Iivonen, M. Vainio, P. Alku, R.J. Ilmoniemi, A. Luuk, J. Allik, J. Sinkkonen and K. Alho, Language-specific phoneme representations revealed by electric and magnetic brain responses. Nature, 385 (1997) 432-434.] were recorded from 13 Japanese subjects (right-handed). Infrequently presented vowels ([o]) among repetitive vowels ([e]) elicited the magnetic counterpart of mismatch negativity, MMNm (Bilateral, nine subjects; Left hemisphere alone, three subjects; Right hemisphere alone, one subject). The estimated source of the MMNm was stronger in the left than in the right auditory cortex. The sources were located posteriorly in the left than in the right auditory cortex. These findings are consistent with the results obtained in Finnish [R. Näätänen, A. Lehtokoski, M. Lennes, M. Cheour, M. Huotilainen, A. Iivonen, M.Vainio, P.Alku, R.J. Ilmoniemi, A. Luuk, J. Allik, J. Sinkkonen and K. Alho, Language-specific phoneme representations revealed by electric and magnetic brain responses. Nature, 385 (1997) 432-434.][T. Rinne, K. Alho, P. Alku, M. Holi, J. Sinkkonen, J. Virtanen, O. Bertrand and R. Näätänen, Analysis of speech sounds is left-hemisphere predominant at 100-150 ms after sound onset. Neuroreport, 10 (1999) 1113-1117.] and English [K. Alho, J.F. Connolly, M. Cheour, A. Lehtokoski, M. Huotilainen, J. Virtanen, R. Aulanko and R.J. Ilmoniemi, Hemispheric lateralization in preattentive processing of speech sounds. Neurosci. Lett., 258 (1998) 9-12.] subjects. Instead of the P1m observed in Finnish [M. Tervaniemi, A. Kujala, K. Alho, J. Virtanen, R.J. Ilmoniemi and R. Näätänen, Functional specialization of the human auditory cortex in processing phonetic and musical sounds: A magnetoencephalographic (MEG) study. Neuroimage, 9 (1999) 330-336.] and English [K. Alho, J. F. Connolly, M. Cheour, A. Lehtokoski, M. Huotilainen, J. Virtanen, R. Aulanko

  19. [Difficulties in face identification after lesion in the left hemisphere].

    Science.gov (United States)

    Verstichel, P; Chia, L

    1999-11-01

    A 82 year-old right-handed man, without any intellectual impairment, suffered from an acute neurological deficit consisting in letter-by-letter reading, right superior quadrant hemianopia with achromatopia in the lower quadrant, and anomia. Cerebral MRI showed an infarct involving the ventral structures of the left hemisphere sparing the splenium of the corpus callosum and the thalamus. Neuropsychological examination revealed that the patient easily identified the objects, the animals and the famous places he could not name: his comments attested normal visual recognition. Conversely, when he was presented with famous faces, he always had a strong feeling of familiarity, but could not provide accurate information about the corresponding individual. Biographic information about personalities was not impaired in the semantic-biographic store, because it could be accessed from the names. Activation of face recognition units (where the visual description provided by the structural encoding and the stored sets of descriptions of familiar faces are compared), was effective, since the patient could distinguish famous faces from unknown ones. In a modular-sequential model of face recognition, this deficit is interpreted as a disconnection between face recognition units and person identity nodes (which are considered to contain semantic-biographic information about individuals). This kind of disturbance differs from classic prosopagnosia in which, characteristically, the patients are unable to experience a feeling of familiarity when viewing famous faces, and to perform a categorization between famous and unknown faces. Right hemisphere has a preponderant role in structural analysis of faces and in activation of face recognition units. The integrity of this hemisphere in this patient could explain the preservation of these two steps of processing. Left-hemisphere specific function in facial recognition enabled access to semantic-biographic store in a conscious, verbal and

  20. Othello syndrome in a patient with two left hemispheric tumors

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    Po-Kuan Yeh

    2016-01-01

    Full Text Available We report a case of a patient with Othello syndrome caused by two left hemispheric tumors. This 50-year-old female had experienced seizures for 10 years and developed manic-like symptoms, delusions of jealousy, persecution and being watched, auditory hallucinations, irritable mood, and violent and disorganized behavior for the past 3 years. Brain imaging studies revealed two left frontal tumors, the larger of which was causing a mass effect. The delusions of jealousy in Othello syndrome resolved after removing the larger tumor, and the other psychiatric symptoms improved after treatment with psychotropic medications. This report aims to raise awareness of Othello syndrome related to disruptions in cortico-subcortical connections in the left orbitofrontal region. Timely surgical treatment may prevent associated psychiatric comorbidities and increase the likelihood of a good outcome.

  1. Right-hemispheric processing of non-linguistic word features: implications for mapping language recovery after stroke.

    Science.gov (United States)

    Baumgaertner, Annette; Hartwigsen, Gesa; Roman Siebner, Hartwig

    2013-06-01

    Verbal stimuli often induce right-hemispheric activation in patients with aphasia after left-hemispheric stroke. This right-hemispheric activation is commonly attributed to functional reorganization within the language system. Yet previous evidence suggests that functional activation in right-hemispheric homologues of classic left-hemispheric language areas may partly be due to processing nonlinguistic perceptual features of verbal stimuli. We used functional MRI (fMRI) to clarify the role of the right hemisphere in the perception of nonlinguistic word features in healthy individuals. Participants made perceptual, semantic, or phonological decisions on the same set of auditorily and visually presented word stimuli. Perceptual decisions required judgements about stimulus-inherent changes in font size (visual modality) or fundamental frequency contour (auditory modality). The semantic judgement required subjects to decide whether a stimulus is natural or man-made; the phonologic decision required a decision on whether a stimulus contains two or three syllables. Compared to phonologic or semantic decision, nonlinguistic perceptual decisions resulted in a stronger right-hemispheric activation. Specifically, the right inferior frontal gyrus (IFG), an area previously suggested to support language recovery after left-hemispheric stroke, displayed modality-independent activation during perceptual processing of word stimuli. Our findings indicate that activation of the right hemisphere during language tasks may, in some instances, be driven by a "nonlinguistic perceptual processing" mode that focuses on nonlinguistic word features. This raises the possibility that stronger activation of right inferior frontal areas during language tasks in aphasic patients with left-hemispheric stroke may at least partially reflect increased attentional focus on nonlinguistic perceptual aspects of language. Copyright © 2012 Wiley Periodicals, Inc.

  2. Testing the language of German cerebral palsy patients with right hemispheric language organization after early left hemispheric damage.

    Science.gov (United States)

    Schwilling, Eleonore; Krägeloh-Mann, Ingeborg; Konietzko, Andreas; Winkler, Susanne; Lidzba, Karen

    2012-02-01

    Language functions are generally represented in the left cerebral hemisphere. After early (prenatally acquired or perinatally acquired) left hemispheric brain damage language functions may be salvaged by reorganization into the right hemisphere. This is different from brain lesions acquired in adulthood which normally lead to aphasia. Right hemispheric reorganized language (RL) is not associated with obvious language deficits. In this pilot study we compared a group of German-speaking patients with left hemispheric brain damage and RL with a group of matched healthy controls. The novel combination of reliable language lateralization as assessed by neuroimaging (functional magnetic resonance imaging) and specific linguistic tasks revealed significant differences between patients with RL and healthy controls in both language comprehension and production. Our results provide evidence for the hypothesis that RL is significantly different from normal left hemispheric language. This knowledge can be used to improve counselling of parents and to develop specific therapeutic approaches.

  3. Beyond Hemispheric Dominance: Brain Regions Underlying the Joint Lateralization of Language and Arithmetic to the Left Hemisphere

    Science.gov (United States)

    Pinel, Philippe; Dehaene, Stanislas

    2010-01-01

    Language and arithmetic are both lateralized to the left hemisphere in the majority of right-handed adults. Yet, does this similar lateralization reflect a single overall constraint of brain organization, such an overall "dominance" of the left hemisphere for all linguistic and symbolic operations? Is it related to the lateralization of specific…

  4. Reorganization of syntactic processing following left-hemisphere brain damage: does right-hemisphere activity preserve function?

    Science.gov (United States)

    Tyler, Lorraine K; Wright, Paul; Randall, Billi; Marslen-Wilson, William D; Stamatakis, Emmanuel A

    2010-11-01

    The extent to which the human brain shows evidence of functional plasticity across the lifespan has been addressed in the context of pathological brain changes and, more recently, of the changes that take place during healthy ageing. Here we examine the potential for plasticity by asking whether a strongly left-lateralized system can successfully reorganize to the right-hemisphere following left-hemisphere brain damage. To do this, we focus on syntax, a key linguistic function considered to be strongly left-lateralized, combining measures of tissue integrity, neural activation and behavioural performance. In a functional neuroimaging study participants heard spoken sentences that differentially loaded on syntactic and semantic information. While healthy controls activated a left-hemisphere network of correlated activity including Brodmann areas 45/47 and posterior middle temporal gyrus during syntactic processing, patients activated Brodmann areas 45/47 bilaterally and right middle temporal gyrus. However, voxel-based morphometry analyses showed that only tissue integrity in left Brodmann areas 45/47 was correlated with activity and performance; poor tissue integrity in left Brodmann area 45 was associated with reduced functional activity and increased syntactic deficits. Activity in the right-hemisphere was not correlated with damage in the left-hemisphere or with performance. Reduced neural integrity in the left-hemisphere through brain damage or healthy ageing results in increased right-hemisphere activation in homologous regions to those left-hemisphere regions typically involved in the young. However, these regions do not support the same linguistic functions as those in the left-hemisphere and only indirectly contribute to preserved syntactic capacity. This establishes the unique role of the left hemisphere in syntax, a core component in human language.

  5. Hospital acquired pneumonia is linked to right hemispheric peri-insular stroke.

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    André Kemmling

    Full Text Available Hospital acquired pneumonia (HAP is a major complication of stroke. We sought to determine associations between infarction of specific brain regions and HAP.215 consecutive acute stroke patients with HAP (2003-2009 were carefully matched with 215 non-pneumonia controls by gender, then NIHSS, then age. Admission imaging and binary masks of infarction were registered to MNI-152 space. Regional atlas and voxel-based log-odds were calculated to assess the relationship between infarct location and the likelihood of HAP. An independently validated penalized conditional logistic regression model was used to identify HAP associated imaging regions.The HAP and control patients were well matched by gender (100%, age (95% within 5-years, NIHSS (98% within 1-point, infarct size, dysphagia, and six other clinical variables. Right hemispheric infarcts were more frequent in patients with HAP versus controls (43.3% vs. 34.0%, p = 0.054, whereas left hemispheric infarcts were more frequent in controls (56.7% vs. 44.7%, p = 0.012; there was no significant difference between groups in the rate of brainstem strokes (p = 1.0. Of the 10 most infarcted regions, only right insular cortex volume was different in HAP versus controls (20 vs. 12 ml, p = 0.02. In univariate analyses, the highest log-odds regions for pneumonia were right hemisphere, cerebellum, and brainstem. The best performing multivariate model selected 7 brain regions of infarction and 2 infarct volume-based variables independently associated with HAP.HAP is associated with right hemispheric peri-insular stroke. These associations may be related to autonomic modulation of immune mechanisms, supporting recent hypotheses of stroke mediated immune suppression.

  6. Anosognosia in patients with acute hemispheric ischemic stroke

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    V. N. Grigoryeva

    2016-01-01

    Full Text Available Objective: to investigate the frequency of anosognosia (a deficit of self-awareness, its anatomic correlates associated with other neuropsychological and neurological disorders in acute hemispheric ischemic stroke (IS.Patients and methods 150 patients (83 men and 67 women; mean age, 63.0±9.3 years with acute hemispheric IS were examined. All the patients underwent neurological, neuroimaging, and neuropsychological (by the procedure described by A.R. Luria examinations. neuropsychological investigations. Anosognosia was diagnosed using the Dysexecutive Questionnaire (DEX and the authors' procedure involving a scale to measure impaired self-rating of motor abilities and a scale to measure impaired self-rating of cognitive abilities in everyday life.Results and discussion. In the acute period of hemispheric IS, reduced self-awareness of motor and cognitive abilities was noted in 14% of the patients and unawareness of only cognitive abilities was recorded in 15%. Patients with anosognosia and cognitive dysfunction (ACD and those with anosognosia and motor dysfunction (AMD had right-sided hemispheric IS more frequently (76% while this was not found in patients with isolated ACD. The development of anosognosia for paralysis and paresis was favored by the large sizes of an ischemic focus that involved a few lobes in the posterior regions of the brain although no lesions were found in the anosognosia-specific anatomical regions. ACD and AMD proved to be associated with unilateral spatial and tactile neglect and obvious regulatory dysfunction. 

  7. Visual search for item- and array-centred locations in patients with left middle cerebral artery stroke

    NARCIS (Netherlands)

    Hildebrandt, H.; Schütze, C.; Ebke, M.; Eling, P.A.T.M.

    2005-01-01

    In this study we systematically explored the impact of left hemisphere lesions on array-centred and item-centred spatial attention. We investigated 16 LH first ever stroke patients, focusing on strokes of the Middle Cerebral Artery (MCA), and 15 healthy control subjects with a parallel and serial

  8. The effects of left and right monocular viewing on hemispheric activation.

    Science.gov (United States)

    Wang, Chao; Burtis, D Brandon; Ding, Mingzhou; Mo, Jue; Williamson, John B; Heilman, Kenneth M

    2018-03-01

    Prior research has revealed that whereas activation of the left hemisphere primarily increases the activity of the parasympathetic division of the autonomic nervous system, right-hemisphere activation increases the activity of the sympathetic division. In addition, each hemisphere primarily receives retinocollicular projections from the contralateral eye. A prior study reported that pupillary dilation was greater with left- than with right-eye monocular viewing. The goal of this study was to test the alternative hypotheses that this asymmetric pupil dilation with left-eye viewing was induced by activation of the right-hemispheric-mediated sympathetic activity, versus a reduction of left-hemisphere-mediated parasympathetic activity. Thus, this study was designed to learn whether there are changes in hemispheric activation, as measured by alteration of spontaneous alpha activity, during right versus left monocular viewing. High-density electroencephalography (EEG) was recorded from healthy participants viewing a crosshair with their right, left, or both eyes. There was a significantly less alpha power over the right hemisphere's parietal-occipital area with left and binocular viewing than with right-eye monocular viewing. The greater relative reduction of right-hemisphere alpha activity during left than during right monocular viewing provides further evidence that left-eye viewing induces greater increase in right-hemisphere activation than does right-eye viewing.

  9. Reorganization of the Cerebro-Cerebellar Network of Language Production in Patients with Congenital Left-Hemispheric Brain Lesions

    Science.gov (United States)

    Lidzba, K.; Wilke, M.; Staudt, M.; Krageloh-Mann, I.; Grodd, W.

    2008-01-01

    Patients with congenital lesions of the left cerebral hemisphere may reorganize language functions into the right hemisphere. In these patients, language production is represented homotopically to the left-hemispheric language areas. We studied cerebellar activation in five patients with congenital lesions of the left cerebral hemisphere to assess…

  10. Hemispheric specificity for proprioception: Postural control of standing following right or left hemisphere damage during ankle tendon vibration.

    Science.gov (United States)

    Duclos, Noémie C; Maynard, Luc; Abbas, Djawad; Mesure, Serge

    2015-11-02

    Right brain damage (RBD) following stroke often causes significant postural instability. In standing (without vision), patients with RBD are more unstable than those with left brain damage (LBD). We hypothesised that this postural instability would relate to the cortical integration of proprioceptive afferents. The aim of this study was to use tendon vibration to investigate whether these changes were specific to the paretic or non-paretic limbs. 14 LBD, 12 RBD patients and 20 healthy subjects were included. Displacement of the Centre of Pressure (CoP) was recorded during quiet standing, then during 3 vibration conditions (80 Hz - 20s): paretic limb, non-paretic limb (left and right limbs for control subjects) and bilateral. Vibration was applied separately to the peroneal and Achilles tendons. Mean antero-posterior position of the CoP, variability and velocity were calculated before (4s), during and after (24s) vibration. For all parameters, the strongest perturbation was during Achilles vibrations. The Achilles non-paretic condition induced a larger backward displacement than the Achilles paretic condition. This condition caused specific behaviour on the velocity: the LBD group was perturbed at the onset of the vibrations, but gradually recovered their stability; the RBD group was significantly perturbed thereafter. After bilateral Achilles vibration, RBD patients required the most time to restore initial posture. The reduction in use of information from the paretic limb may be a central strategy to deal with risk-of-fall situations such as during Achilles vibration. The postural behaviour is profoundly altered by lesions of the right hemisphere when proprioception is perturbed. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Right cerebral hemisphere specialization for quiet and perturbed body balance control: Evidence from unilateral stroke.

    Science.gov (United States)

    Fernandes, Corina Aparecida; Coelho, Daniel Boari; Martinelli, Alessandra Rezende; Teixeira, Luis Augusto

    2018-02-01

    Our aim in this investigation was to assess the relative importance of each cerebral hemisphere in quiet and perturbed balance, based on uni-hemispheric lesions by stroke. We tested the hypothesis of right cerebral hemisphere specialization for balance control. Groups of damage either to the right (RHD, n=9) or the left (LHD, n=7) cerebral hemisphere were compared across tasks requiring quiet balance or body balance recovery following a mechanical perturbation, comparing them to age-matched nondisabled individuals (controls, n=24). They were evaluated in conditions of full and occluded vision. In Experiment 1, the groups were compared in the task of quiet standing on (A) rigid and (B) malleable surfaces, having as outcome measures center of pressure (CoP) amplitude and velocity sway. In Experiment 2, we evaluated the recovery of body balance following a perturbation inducing forward body oscillation, having as outcome measures CoP displacement, peak hip and ankle rotations and muscular activation of both legs. Results from Experiment 1 showed higher values of CoP sway velocity for RHD in comparison to LHD and controls in the anteroposterior (rigid surface) and mediolateral (malleable surface) directions, while LHD had lower balance stability than the controls only in the mediolateral direction when supported on the rigid surface. In Experiment 2 results showed that RHD led to increased values in comparison to LHD and controls for anteroposterior CoP displacement and velocity, time to CoP direction reversion, hip rotation, and magnitude of muscular activation in the paretic leg, while LHD was found to differ in comparison to controls in magnitude of muscular activation of the paretic leg and amplitude of mediolateral sway only. These results suggest that damage to the right as compared to the left cerebral hemisphere by stroke leads to poorer postural responses both in quiet and perturbed balance. That effect was not altered by manipulation of sensory information

  12. The effects of motivational reward on the pathological attentional blink following right hemisphere stroke.

    Science.gov (United States)

    Li, Korina; Russell, Charlotte; Balaji, Nikita; Saleh, Youssuf; Soto, David; Malhotra, Paresh A

    2016-11-01

    Recent work has shown that attentional deficits following stroke can be modulated by motivational stimulation, particularly anticipated monetary reward. Here we examined the effects of anticipated reward on the pathological attentional blink (AB), an index of temporal selective attention, which is prolonged in patients with right hemisphere damage and a history of left neglect. We specifically compared the effects of reward versus feedback-without-reward on the AB in 17 patients. We found that the patients all manifested impaired performance compared to healthy controls and that reward modulated the pathological blink in the patient group, but only in the second experimental session. When the performance of patients whose neglect had recovered was compared with that of patients who had ongoing or persistent neglect, reward appeared to only influence the AB in the former. These results have implications for our understanding of motivation-attention interactions following right hemisphere stroke, and how they may impact upon recovery from spatial neglect. Copyright © 2016. Published by Elsevier Ltd.

  13. Characteristics and dynamics of cognitive impairment in patients with primary and recurrent cerebral ischemic hemispheric stroke

    Directory of Open Access Journals (Sweden)

    A. A. Kozyolkin

    2014-08-01

    Full Text Available Acute cerebrovascular disease is a global medical and social problem of the modern angioneurology, occupying leading positions in the structure of morbidity and mortality among adult population of the world. Ischemic stroke – is one of the most common pathology. Today this disease took out the world pandemic. More than 16 million new cases of cerebral infarction recorded in the world each year and it “kills” about 7 million of people. About 111,953 cases of cerebral stroke were registered in 2013 in Ukraine. Cognitive impairment, t hat significantly disrupt daily activities and life of the patient, is one of the most significant post-stroke complications that have social, medical and biological significance. Aim. The purpose of this investigation was to study features and dynamics of cognitive impairments in patients with primary and recurrent cerebral hemispheric ischemic stroke (CHIS in the acute stage of the disease. Materials and methods. To achieve the aim, and the decision of tasks in the clinic of nervous diseases Zaporozhye State Medical University (supervisor - Doctor of Medicine, Professor Kozelkin A. based on the department of acute cerebrovascular disease were performed comparative, prospective cohort study, which included comprehensive clinical and paraclinical examinations of 41 patients (26 men and 15 women aged 45 to 85 years (mean age 66,4 ± 1,4 years with acute left-hemispheric (2 patients and right - hemispheric (39 patients CHIS . First up was a group of 28 patients (19 men and 9 women, mean age 65,6 ± 1,6 years, who suffered from primary CHIS. The second group consisted of 13 patients (7 men and 6 women, mean age 68,1 ± 2,5 years with recurrent CHIS. The groups were matched by age, sex, localization of the lesion and the initial level of neurological deficit. All patients underwent physical examination, neurological examination. Dynamic clinical neurological examination assessing the severity of stroke was conducted

  14. The assessment of visuo-spatial neglect after acute stroke.

    OpenAIRE

    Stone, S P; Wilson, B; Wroot, A; Halligan, P W; Lange, L S; Marshall, J C; Greenwood, R J

    1991-01-01

    Forty four consecutive patients with acute hemispheric stroke and forty seven elderly controls with no neurological disease were assessed for visuo-spatial neglect, using a modified neglect test battery. Neglect was found to be equally common in patients with right hemisphere and left hemisphere stroke three days after stroke (72% versus 62%). It was more severe in those with a right hemisphere stroke and resolved more frequently in those with a left hemisphere stroke. The battery was validat...

  15. When right is all that's left: plasticity of right-hemisphere tracts in a young aphasic patient

    Science.gov (United States)

    Zipse, Lauryn; Norton, Andrea; Marchina, Sarah; Schlaug, Gottfried

    2012-01-01

    Using an adapted version of melodic intonation therapy (MIT), we treated an adolescent girl with a very large left-hemisphere lesion and severe nonfluent aphasia secondary to an ischemic stroke. At the time of her initial assessment 1.25 years after her stroke, she had reached a plateau in her recovery despite intense and long-term traditional speech-language therapy (approximately five times per week for more than one year). Following an intensive course of treatment with our adapted form of MIT, her performance improved on both trained and untrained phrases, as well as on speech and language tasks. These behavioral improvements were accompanied by functional MRI changes in the right frontal lobe as well as by an increased volume of white matter pathways in the right hemisphere. No increase in white matter volume was seen in her healthy twin sister, who was scanned twice over the same time period. This case study not only provides further evidence for MIT's effectiveness, but also indicates that intensive treatment can induce functional and structural changes in a right hemisphere fronto-temporal network. PMID:22524365

  16. When right is all that is left: plasticity of right-hemisphere tracts in a young aphasic patient.

    Science.gov (United States)

    Zipse, Lauryn; Norton, Andrea; Marchina, Sarah; Schlaug, Gottfried

    2012-04-01

    Using an adapted version of Melodic Intonation Therapy (MIT), we treated an adolescent girl with a very large left-hemisphere lesion and severe nonfluent aphasia secondary to an ischemic stroke. At the time of her initial assessment 15 months after her stroke, she had reached a plateau in her recovery despite intense and long-term traditional speech-language therapy (approximately five times per week for more than one year). Following an intensive course of treatment with our adapted form of MIT, her performance improved on both trained and untrained phrases, as well as on speech and language tasks. These behavioral improvements were accompanied by functional MRI changes in the right frontal lobe as well as by an increased volume of white matter pathways in the right hemisphere. No increase in white matter volume was seen in her healthy twin sister, who was scanned twice over the same time period. This case study not only provides further evidence for MIT's effectiveness, but also indicates that intensive treatment can induce functional and structural changes in a right-hemisphere fronto-temporal network. © 2012 New York Academy of Sciences.

  17. Motor imagery cognitive network after left ischemic stroke: study of the patients during mental rotation task.

    Directory of Open Access Journals (Sweden)

    Jing Yan

    Full Text Available Although motor imagery could improve motor rehabilitation, the detailed neural mechanisms of motor imagery cognitive process of stroke patients, particularly from functional network perspective, remain unclear. This study investigated functional brain network properties in each cognitive sub-stage of motor imagery of stroke patients with ischemic lesion in left hemisphere to reveal the impact of stroke on the cognition of motor imagery. Both stroke patients and control subjects participated in mental rotation task, which includes three cognitive sub-stages: visual stimulus perception, mental rotation and response cognitive process. Event-related electroencephalograph was recorded and interdependence between two different cortical areas was assessed by phase synchronization. Both global and nodal properties of functional networks in three sub-stages were statistically analyzed. Phase synchronization of stroke patients significantly reduced in mental rotation sub-stage. Longer characteristic path length and smaller global clustering coefficient of functional network were observed in patients in mental rotation sub-stage which implied the impaired segregation and integration. Larger nodal clustering coefficient and betweenness in contralesional occipitoparietal and frontal area respectively were observed in patients in all sub-stages. In addition, patients also showed smaller betweenness in ipsilesional central-parietal area in response sub-stage. The compensatory effects on local connectedness and centrality indicated the neuroplasticity in contralesional hemisphere. The functional brain networks of stroke patients demonstrated significant alterations and compensatory effects during motor imagery.

  18. A Test of Some Models of Hemispheric Speech Organization in the Left- and Right-Handed.

    Science.gov (United States)

    Satz, Paul

    1979-01-01

    A new method generates specific predictions concerning the expected frequencies of aphasia after unilateral injury to the brain in the left- and right-handed. These predictions are then compared with the observed data for all known studies between 1935 and 1973 to derive the best-fitting model of hemispheric speech lateralization in the left- and…

  19. Dissociation between Semantic Representations for Motion and Action Verbs: Evidence from Patients with Left Hemisphere Lesions.

    Science.gov (United States)

    Taylor, Lawrence J; Evans, Carys; Greer, Joanna; Senior, Carl; Coventry, Kenny R; Ietswaart, Magdalena

    2017-01-01

    This multiple single case study contrasted left hemisphere stroke patients ( N = 6) to healthy age-matched control participants ( N = 15) on their understanding of action (e.g., holding, clenching) and motion verbs (e.g., crumbling, flowing). The tasks required participants to correctly identify the matching verb or associated picture. Dissociations on action and motion verb content depending on lesion site were expected. As predicted for verbs containing an action and/or motion content, modified t -tests confirmed selective deficits in processing motion verbs in patients with lesions involving posterior parietal and lateral occipitotemporal cortex. In contrast, deficits in verbs describing motionless actions were found in patients with more anterior lesions sparing posterior parietal and lateral occipitotemporal cortex. These findings support the hypotheses that semantic representations for action and motion are behaviorally and neuro-anatomically dissociable. The findings clarify the differential and critical role of perceptual and motor regions in processing modality-specific semantic knowledge as opposed to a supportive but not necessary role. We contextualize these results within theories from both cognitive psychology and cognitive neuroscience that make claims over the role of sensory and motor information in semantic representation.

  20. Moral judgement by the disconnected left and right cerebral hemispheres: a split-brain investigation.

    Science.gov (United States)

    Steckler, Conor M; Hamlin, J Kiley; Miller, Michael B; King, Danielle; Kingstone, Alan

    2017-07-01

    Owing to the hemispheric isolation resulting from a severed corpus callosum, research on split-brain patients can help elucidate the brain regions necessary and sufficient for moral judgement. Notably, typically developing adults heavily weight the intentions underlying others' moral actions, placing greater importance on valenced intentions versus outcomes when assigning praise and blame. Prioritization of intent in moral judgements may depend on neural activity in the right hemisphere's temporoparietal junction, an area implicated in reasoning about mental states. To date, split-brain research has found that the right hemisphere is necessary for intent-based moral judgement. When testing the left hemisphere using linguistically based moral vignettes, split-brain patients evaluate actions based on outcomes, not intentions. Because the right hemisphere has limited language ability relative to the left, and morality paradigms to date have involved significant linguistic demands, it is currently unknown whether the right hemisphere alone generates intent-based judgements. Here we use nonlinguistic morality plays with split-brain patient J.W. to examine the moral judgements of the disconnected right hemisphere, demonstrating a clear focus on intent. This finding indicates that the right hemisphere is not only necessary but also sufficient for intent-based moral judgement, advancing research into the neural systems supporting the moral sense.

  1. Weakness of Eye Closure with Central Facial Paralysis after Unilateral Hemispheric Stroke Predicts a Worse Outcome.

    Science.gov (United States)

    Lin, Jianwen; Chen, Yicong; Wen, Hongmei; Yang, Zhiyun; Zeng, Jinsheng

    2017-04-01

    Upper facial dysfunction is not generally considered a feature of central facial paralysis after unilateral hemispheric stroke; however, weakness of eye closure (WEC) has been observed in some cases. We aimed to investigate the frequency and characteristics of WEC in unilateral stroke and its association with stroke prognosis. Patients with unilateral stroke and central facial paralysis were prospectively recruited within 7 days of onset. Facial paralysis was evaluated via the fourth item in the National Institute of Health Stroke Scale (NIHSS-4) and the Japan Facial Score (JFS) on admission, and at days 7, 14, 21, and 30 after stroke. Eye closure strength was measured daily using an ergometer for 30 days after stroke. Primary outcome was assessed using the modified Rankin Scale (mRS) at 90 and 180 days. Univariate and multivariate analyses were performed to investigate risk factors of WEC. WEC was identified in 16 of 242 patients (6.6%). Baseline characteristics, stroke risk factors, and lesion volume were not significantly different between patients with and patients without WEC. Patients with WEC featured higher NIHSS-4 scores and lower JFS between admission and at 21 days after stroke. Severe central facial paralysis (odds ratio [OR] = 8.1, 95% confidence interval [CI] = 2.3-28.6, P = .001) and right hemispheric stroke (OR = 13.7, 95% CI = 3.7-51.2, P WEC. At 180 days after stroke, patients with WEC demonstrated a lower rate of functional independence (mRS = 0-2: 37.5% versus 72.1%, P WEC, which predicts a worse functional outcome at 180 days after unilateral stroke, demonstrates an association with severe central facial paralysis and right hemispheric stroke. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  2. Right-ear precedence and vocal emotion contagion: The role of the left hemisphere.

    Science.gov (United States)

    Schepman, Astrid; Rodway, Paul; Cornmell, Louise; Smith, Bethany; de Sa, Sabrina Lauren; Borwick, Ciara; Belfon-Thompson, Elisha

    2018-05-01

    Much evidence suggests that the processing of emotions is lateralized to the right hemisphere of the brain. However, under some circumstances the left hemisphere might play a role, particularly for positive emotions and emotional experiences. We explored whether emotion contagion was right-lateralized, lateralized valence-specifically, or potentially left-lateralized. In two experiments, right-handed female listeners rated to what extent emotionally intoned pseudo-sentences evoked target emotions in them. These sound stimuli had a 7 ms ear lead in the left or right channel, leading to stronger stimulation of the contralateral hemisphere. In both experiments, the results revealed that right ear lead stimuli received subtly but significantly higher evocation scores, suggesting a left hemisphere dominance for emotion contagion. A control experiment using an emotion identification task showed no effect of ear lead. The findings are discussed in relation to prior findings that have linked the processing of emotional prosody to left-hemisphere brain regions that regulate emotions, control orofacial musculature, are involved in affective empathy processing areas, or have an affinity for processing emotions socially. Future work is needed to eliminate alternative interpretations and understand the mechanisms involved. Our novel binaural asynchrony method may be useful in future work in auditory laterality.

  3. Reducing chronic visuo-spatial neglect following right hemisphere stroke through instrument playing

    Directory of Open Access Journals (Sweden)

    Rebeka eBodak

    2014-06-01

    Full Text Available Unilateral visuo-spatial neglect is a neuropsychological syndrome commonly resulting from right hemisphere strokes at the temporo-parietal junction of the infero-posterior parietal cortex. Neglect is characterised by reduced awareness of stimuli presented on patients’ contralesional side of space and has previously been shown to be improved by a number of motivational influences, including listening to preferred music and numerical sequence completion. Here we examined whether playing musical sequences on chime bars – an instrument with a horizontal alignment – would bring about clinically significant improvement in chronic neglect.Two left neglect patients completed an intervention comprising four weekly 30-minute music sessions involving playing scales and familiar melodies on chime bars from right to left. Two cancellation tests (Mesulam shape, BIT star, the line bisection test, and the neglect subtest from the computerised TAP (Test for Attentional Performance battery were administered three times during a preliminary baseline phase, before and after each music session during the rehabilitation phase to investigate short-term effects, as well as one week after the last intervention session to investigate whether any effects would persist.Both patients demonstrated significant short-term and longer-lasting improvements on the Mesulam shape cancellation test. One patient also showed longer-lasting effects on the BIT star cancellation test and scored in the normal range one week after the intervention. These findings provide preliminary evidence that active music-making may help neglect patients attend more to their affected side.

  4. Opposed Left and Right Brain Hemisphere Contributions to Sexual Drive: A Multiple Lesion Case Analysis

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    Claude M. J. Braun

    2003-01-01

    Full Text Available Brain topographical studies of normal men have have shown that sexual excitation is asymmetric in the brain hemispheres. Group studies of patients with unilateral epileptic foci and other studies of patients with unilateral brain lesions have come to the same conclusion. The present study reviewed previously published single case reports of patients with frank hypo or hypersexuality subsequent to a unilateral brain lesion. Hyposexual patients tended to have left hemisphere lesions (primarily of the temporal lobe, and hypersexual patients tended to have right hemisphere lesions (primarily of the temporal lobe (p < 0.05. We interpret this double dissociation as part of a more general phenomenon of psychic tone similarly dissociated with regard to hemispheric control, including mood, psychomotor baseline, speech rate, and even immunity. The behavioral significance of this psychic tone is to modulate approach versus avoidance behavior.

  5. Left hemisphere EEG coherence in infancy predicts infant declarative pointing and preschool epistemic language.

    Science.gov (United States)

    Kühn-Popp, N; Kristen, S; Paulus, M; Meinhardt, J; Sodian, B

    2016-01-01

    Pointing plays a central role in preverbal communication. While imperative pointing aims at influencing another person's behavior, declarative gestures serve to convey epistemic information and to share interest in an object. Further, the latter are hypothesized to be a precursor ability of epistemic language. So far, little is known about their underlying brain maturation processes. Therefore, the present study investigated the relation between brain maturation processes and the production of imperative and declarative motives as well as epistemic language in N = 32 infants. EEG coherence scores were measured at 14 months, imperative and declarative point production at 15 months and epistemic language at 48 months. Results of correlational analyses suggest distinct behavioral and neural patterns for imperative and declarative pointing, with declarative pointing being associated with the maturation of the left hemisphere. Further, EEG coherence measures of the left hemisphere at 14 months and declarative pointing at 15 months are related to individual differences in epistemic language skills at 48 months, independently of child IQ. In regression analyses, coherence measures of the left hemisphere prove to be the most important predictor of epistemic language skills. Thus, neural processes of the left hemisphere seem particularly relevant to social communication.

  6. Increased left hemisphere impairment in high-functioning autism: a tract based spatial statistics study.

    Science.gov (United States)

    Perkins, Thomas John; Stokes, Mark Andrew; McGillivray, Jane Anne; Mussap, Alexander Julien; Cox, Ivanna Anne; Maller, Jerome Joseph; Bittar, Richard Garth

    2014-11-30

    There is evidence emerging from Diffusion Tensor Imaging (DTI) research that autism spectrum disorders (ASD) are associated with greater impairment in the left hemisphere. Although this has been quantified with volumetric region of interest analyses, it has yet to be tested with white matter integrity analysis. In the present study, tract based spatial statistics was used to contrast white matter integrity of 12 participants with high-functioning autism or Aspergers syndrome (HFA/AS) with 12 typically developing individuals. Fractional Anisotropy (FA) was examined, in addition to axial, radial and mean diffusivity (AD, RD and MD). In the left hemisphere, participants with HFA/AS demonstrated significantly reduced FA in predominantly thalamic and fronto-parietal pathways and increased RD. Symmetry analyses confirmed that in the HFA/AS group, WM disturbance was significantly greater in the left compared to right hemisphere. These findings contribute to a growing body of literature suggestive of reduced FA in ASD, and provide preliminary evidence for RD impairments in the left hemisphere. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Functional characteristics of developmental dyslexia in left-hemispheric posterior brain regions predate reading onset.

    Science.gov (United States)

    Raschle, Nora Maria; Zuk, Jennifer; Gaab, Nadine

    2012-02-07

    Individuals with developmental dyslexia (DD) show a disruption in posterior left-hemispheric neural networks during phonological processing. Additionally, compensatory mechanisms in children and adults with DD have been located within frontal brain areas. However, it remains unclear when and how differences in posterior left-hemispheric networks manifest and whether compensatory mechanisms have already started to develop in the prereading brain. Here we investigate functional networks during phonological processing in 36 prereading children with a familial risk for DD (n = 18, average age = 66.50 mo) compared with age and IQ-matched controls (n = 18; average age = 65.61 mo). Functional neuroimaging results reveal reduced activation in prereading children with a family-history of DD (FHD(+)), compared with those without (FHD(-)), in bilateral occipitotemporal and left temporoparietal brain regions. This finding corresponds to previously identified hypoactivations in left hemispheric posterior brain regions for school-aged children and adults with a diagnosis of DD. Furthermore, left occipitotemporal and temporoparietal brain activity correlates positively with prereading skills in both groups. Our results suggest that differences in neural correlates of phonological processing in individuals with DD are not a result of reading failure, but are present before literacy acquisition starts. Additionally, no hyperactivation in frontal brain regions was observed, suggesting that compensatory mechanisms for reading failure are not yet present. Future longitudinal studies are needed to determine whether the identified differences may serve as neural premarkers for the early identification of children at risk for DD.

  8. [Unilateral apraxia of eyelid closure in ischemic stroke: role of the right hemisphere in the emotional gesture communication].

    Science.gov (United States)

    Pérez-Martínez, D A; Puente-Muñoz, A I; Doménech, J; Baztán, J J; Berbel-Garcia, A; Porta-Etessam, J

    Apraxia of eyelid closure (AEC) is an infrequent disorder that is characterised by the inability to close the eyelids on command, although spontaneous blinking and reflex shutting of the eyes is preserved. Very few cases of unilateral AEC have been reported and no long-term follow-ups have been carried out. We report the case of a patient with unilateral AEC that was followed up over a 3-year period and also discuss the role played by the right hemisphere in this disorder. CASE REPORT" We examined the case of a 67-year-old right-handed male who was admitted because of a parietotemporal infarction with extension into the subcortex. A few days after the stroke the patient reported the inability to close his left eye on command, although he was still able to blink spontaneously and the blink and visual threat reflexes were preserved. This deficiency was associated to a dense hemiparesis on the left side and notable aprosodia affecting language. At 3 years' follow-up the AEC had not improved significantly. There are data to suggest that the right hemisphere is related to emotional perception and expressiveness, as well as the regulation of language prosody. Likewise, symbolic anthropology stresses the importance of winking as a gesture involved in non-verbal communication. These data suggest that AEC may be a consequence of a dysfunction of the role played by the right hemisphere in emotional expressiveness through gestures. The association with language aprosodia could support this hypothesis.

  9. Why the Left Hemisphere Is Dominant for Speech Production: Connecting the Dots

    Directory of Open Access Journals (Sweden)

    Harvey Martin Sussman

    2015-12-01

    Full Text Available Evidence from seemingly disparate areas of speech/language research is reviewed to form a unified theoretical account for why the left hemisphere is specialized for speech production. Research findings from studies investigating hemispheric lateralization of infant babbling, the primacy of the syllable in phonological structure, rhyming performance in split-brain patients, rhyming ability and phonetic categorization in children diagnosed with developmental apraxia of speech, rules governing exchange errors in spoonerisms, organizational principles of neocortical control of learned motor behaviors, and multi-electrode recordings of human neuronal responses to speech sounds are described and common threads highlighted. It is suggested that the emergence, in developmental neurogenesis, of a hard-wired, syllabically-organized, neural substrate representing the phonemic sound elements of one’s language, particularly the vocalic nucleus, is the crucial factor underlying the left hemisphere’s dominance for speech production.

  10. [Ischemic stroke induced by a left atrial myxoma].

    Science.gov (United States)

    Hatayama, Sayaka; Ogata, Toshiyasu; Okawa, Masakazu; Higashi, Toshio; Inoue, Tooru; Takano, Koichi; Minematsu, Noritoshi; Tashiro, Tadashi; Sakata, Noriyuki

    2012-10-01

    We reported a case of ischemic stroke induced by a left atrial myxoma. A 76-year-old man was found unconscious and transferred to the emergency ward in our hospital. He experienced consciousness disturbance, motor dominant aphasia, and severe right hemiparesis. His neurological and radiological findings indicated that he had ischemic stroke and was eligible to undergo intravenous thrombolysis. Alteplase was administrated 155 min after the onset of stroke. Intracerebral hemorrhage was not seen 24h after thrombolysis. A tumor in the left atrium was detected on transthoracic echocardiography, and this finding suggested that the tumor was a myxoma. Although cardiac surgery was scheduled, hemorrhagic transformation was found on day 11, which made us postpone the surgery. After the hemorrhage was disappeared, the tumor was resected by open-heart surgery and it was confirmed to be a myxoma. Neither his neurological symptom nor intracerebral hemorrhage was not deteriorated after the operation. Thrombolytic treatment seemed a safe option for ischemic stroke caused by left atrial myxoma. However, we should carefully monitor the extent of anticoagulation therapy because hemorrhagic transformation might alter the timing of surgery for tumor resection.

  11. Estradiol levels during the menstrual cycle differentially affect latencies to right and left hemispheres during dichotic listening: an ERP study.

    Science.gov (United States)

    Tillman, Gail D

    2010-02-01

    Many behavioral studies have found high-estrogen phases of the menstrual cycle to be associated with enhanced left-hemisphere processing and low-estrogen phases to be associated with better right-hemisphere processing. This study examined the changing of hemispheric asymmetry during the menstrual cycle by analyzing event-related potential (ERP) data from midline and both hemispheres of 23 women during their performance of a dichotic tasks shown to elicit a left-hemisphere response (semantic categorization) and a right-hemisphere response (complex tones). Each woman was tested during her high-estrogen follicular phase and low-estrogen menstrual phase. Salivary assays of estradiol and progesterone were used to confirm cycle phase. Analyses of the ERP data revealed that latency for each hemisphere was differentially affected by phase and target side, such that latencies to the left hemisphere and from the right ear were shorter during the high-estrogen phase, and latencies to the right hemisphere and from the left ear were shorter during the low-estrogen phase. These findings supply electrophysiological correlates of the cyclically based interhemispheric differences evinced by behavioral studies. 2009 Elsevier Ltd. All rights reserved.

  12. Cognitive-communication disorder following right hemisphere stroke: exploring rehabilitation access and outcomes.

    Science.gov (United States)

    Hewetson, Ronelle; Cornwell, Petrea; Shum, David

    2017-07-01

    Rehabilitation positively influences return to activities and social roles in people with aphasia. The cognitive-communication disorder (CCD) found following a right hemisphere stroke has been less extensively researched with rehabilitation access and outcomes yet to be determined. To document rehabilitation access and outcomes for people with CCD post-stroke; and compare outcomes based on presence (viz CCD; aphasia) or absence of communication impairment. A retrospective chart audit was completed for patients with first onset unilateral stroke, with a hospital length of stay (LOS) of at least two days and a communication assessment by a speech pathologist. Data extracted included presence and severity of communication impairment, access to and LOS in a rehabilitation unit, and functional outcome measures recorded at rehabilitation discharge. The majority of the 115 patients who met inclusion criteria were living independently (n = 112, 97.4%) at the time of stroke. CCD (66%) was diagnosed with similar frequency to aphasia (68%). The presence of communication impairment did not result in significant differences in rehabilitation LOS and discharge destination when compared to hemispheric strokes without communication impairment. Severity of CCD was an independent predictor of functional gain by rehabilitation discharge. People with CCD require comparable access to rehabilitation as people with aphasia, and severity of CCD should be considered in determining rehabilitation LOS. A large number of people are discharged with ongoing CCD which warrants exploration of potential participation restrictions created by the communication impairment.

  13. Left Atrial Thrombus Causing Stroke and Syncope: Does Size Matters?

    Directory of Open Access Journals (Sweden)

    Surender Deora

    2014-01-01

    Full Text Available Left atrium thrombus is seen in patients with rheumatic heart disease, severe mitral stenosis and/or atrial fibrillation, but is usually immobile and located in left atrial appendage. Freely mobile thrombus is rarely seen, and the size may vary from few millimeters to centimeters. The clinical presentation varies from presyncope or syncope in a small well organized thrombus to transient ischemic attacks or stroke in large poorly organized thrombus. Management includes urgent surgical removal of thrombus with underlying valvular correction and anticoagulation.

  14. The development of pragmatic skills in children after hemispherotomy: Contribution from left and right hemispheres.

    Science.gov (United States)

    Save-Pédebos, Jessica; Pinabiaux, Charlotte; Dorfmuller, Georg; Sorbets, Sarah Ferrand; Delalande, Olivier; Jambaqué, Isabelle; Bulteau, Christine

    2016-02-01

    Hemispherotomy (H) is the standard treatment used to cure hemispheric epileptic syndromes in childhood. The postoperative linguistic profile involves hemispheric specialization processes and developmental cognitive plasticity. This research concerns pragmatic aspects of language as a tool for communication which involves both linguistic and extralinguistic communication in context. Our aim was to analyze whether any correlation exists with age at surgery and side of surgery on pragmatic skills following H. Forty children who underwent H (23 females, 16 right H) were evaluated at a mean age of 12.8 years (±2.6) with two receptive tasks (oral comprehension and syntactic judgment), the Children's Communication Checklist (CCC) rating scale, and the Behavioral Rating Inventory of Executive Function (BRIEF) questionnaire in order to evaluate the role of executive functions on pragmatic skills. Children operated on before the age of 18 months were considered the "early" group (5 right H and 9 left H), while those operated on later were called the "late" group (11 right H and 15 left H). The whole group had significant deficits in all three measures. We demonstrated a statistically significant crossed interaction between the side of H and the age at H with pragmatic language impairments (F(1,36)=17.48; p=.0002) and disorders in executive function (F(1,36)=5.80; p=.021) in left early H and in right late H patients. These findings are consistent with the previous studies of pragmatic language impairments concerning adolescents and adults with right hemisphere damage and emphasize the contribution of structural language in the early stage of verbal communication. These results emphasize for the first time that hemispherotomized children have pragmatic language impairments that are independent of receptive language. Our findings are congruent with the recent theory on pragmatic language development in childhood with evidence of a participation of the left hemisphere at the

  15. Detectability of cerebral hemisphere ischaemic infarcts by CT within 6 h of stroke

    International Nuclear Information System (INIS)

    Kummer, R. von; Nolte, P.N.; Schnittger, H.; Thron, A.; Ringelstein, E.B.

    1996-01-01

    To determine how early and how reliably ischaemic brain infarcts can be detected on CT within 6 h of the onset of cerebral hemisphere strokes, 44 such studies were interpreted by an experienced neuroradiologist blinded to clinical signs, but aware that the cohort was a stroke population. He was asked to detect and localise an area of parenchymal low density and/or focal brain swelling. A follow-up study showing the definite infarct served as a reference in each case. In 38 patients areas of slightly low density were seen, and in 36 follow-up CT confirmed infarcts in the locations indicated. In 2 patients the reading was false positive. In 6 patients no low density focus could be detected. In these 8 patients examined by CT within 180 min of the stroke, no low density could be identified, even in retrospect with the knowledge of the findings on follow-up. Thus, 42 readings (95%) were true positive or true negative; 2 were false positive; and none was a false negative. CT within 6 h of the onset of symptoms has a mean sensitivity of 82% (36/44) for ischaemic cerebral hemisphere infarcts. By contrast, its sensitivity to ischaemic parenchymal low density is low during the initial 2 h. The early development of hemispheric infarcts can be detected reliably if the radiologist is familiar with the signs. (orig.)

  16. Changes of deceleration and acceleration capacity of heart rate in patients with acute hemispheric ischemic stroke

    Directory of Open Access Journals (Sweden)

    Xu YH

    2016-03-01

    Full Text Available Yan-Hong Xu,1 Xing-De Wang,2 Jia-Jun Yang,1 Li Zhou,2 Yong-Chao Pan1 1Department of Neurology, 2Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China Background and purpose: Autonomic dysfunction is common after stroke, which is correlated with unfavorable outcome. Phase-rectified signal averaging is a newly developed technique for assessing cardiac autonomic function, by detecting sympathetic and vagal nerve activity separately through calculating acceleration capacity (AC and deceleration capacity (DC of heart rate. In this study, we used this technique for the first time to investigate the cardiac autonomic function of patients with acute hemispheric ischemic stroke. Methods: A 24-hour Holter monitoring was performed in 63 patients with first-ever acute ischemic stroke in hemisphere and sinus rhythm, as well as in 50 controls with high risk of stroke. DC, AC, heart rate variability parameters, standard deviation of all normal-to-normal intervals (SDNN, and square root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals (RMSSD were calculated. The National Institutes of Health Stroke Scale (NIHSS was used to assess the severity of stroke. We analyzed the changes of DC, AC, SDNN, and RMSSD and also studied the correlations between these parameters and NIHSS scores. Results: The R–R (R wave to R wave on electrocardiogram intervals, DC, AC, and SDNN in the cerebral infarction group were lower than those in controls (P=0.003, P=0.002, P=0.006, and P=0.043, but the difference of RMSSD and the D-value and ratio between absolute value of AC (|AC| and DC were not statistically significant compared with those in controls. The DC of the infarction group was significantly correlated with |AC|, SDNN, and RMSSD (r=0.857, r=0.619, and r=0.358; P=0.000, P=0.000, and P=0.004. Correlation analysis also showed that DC, |AC|, and SDNN

  17. Mapping nouns and finite verbs in left hemisphere tumors: a direct electrical stimulation study.

    Science.gov (United States)

    Rofes, Adrià; Spena, Giannantonio; Talacchi, Andrea; Santini, Barbara; Miozzo, Antonio; Miceli, Gabriele

    2017-04-01

    Neurosurgical mapping studies with nouns and finite verbs are scarce and subcortical data are nonexistent. We used a new task that uses finite verbs in six Italian-speaking patients with gliomas in the left language-dominant hemisphere. Language-relevant positive areas were detected only with nouns in four patients, with both tasks yet in distinct cortical areas in one patient, and only with finite verbs in another patient. Positive areas and types of errors varied across participants. Finite verbs provide complementary information to nouns, and permit more accurate mapping of language production when nouns are unaffected by electrical stimulation.

  18. [A New Diagnostic Tool for Apraxia in Patients with Right-Hemisphere Stroke: The Revised Cologne Apraxia Screening (KAS-R)].

    Science.gov (United States)

    Wirth, K; Held, A; Kalbe, E; Kessler, J; Saliger, J; Karbe, H; Fink, G R; Weiss, P H

    2016-10-01

    The Cologne Apraxia Screening (KAS) was developed to diagnose apraxia following left-hemisphere (LH) stroke. The present study aims at developing a diagnostic tool for patients with right-hemisphere (RH) stroke (KAS-R) by modifying the test material of the KAS and reducing the test items based on psychometric analyses.A total of 100 patients with RH stroke and 77 healthy control participants were tested. Psychometric analyses led to the exclusion of 8 KAS items. The final KAS-R, consisting of 12 items, shows good internal consistency (α = 0.795) as well as high sensitivity (79.4 %) and specificity (84.4 %). Applying a cut-off value of ≤ 46 (out of 48) points, 39 RH stroke patients were diagnosed with apraxia. Significant correlations were found between the KAS-R and an imitation test as well as expert ratings, indicating high construct validity. The results suggest that the KAS-R is a reliable and valid diagnostic tool for apraxic deficits after RH stroke. © Georg Thieme Verlag KG Stuttgart · New York.

  19. Errors on the Trail Making Test Are Associated with Right Hemispheric Frontal Lobe Damage in Stroke Patients

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    Bruno Kopp

    2015-01-01

    Full Text Available Measures of performance on the Trail Making Test (TMT are among the most popular neuropsychological assessment techniques. Completion time on TMT-A is considered to provide a measure of processing speed, whereas completion time on TMT-B is considered to constitute a behavioral measure of the ability to shift between cognitive sets (cognitive flexibility, commonly attributed to the frontal lobes. However, empirical evidence linking performance on the TMT-B to localized frontal lesions is mostly lacking. Here, we examined the association of frontal lesions following stroke with TMT-B performance measures (i.e., completion time and completion accuracy measures using voxel-based lesion-behavior mapping, with a focus on right hemispheric frontal lobe lesions. Our results suggest that the number of errors, but not completion time on the TMT-B, is associated with right hemispheric frontal lesions. This finding contradicts common clinical practice—the use of completion time on the TMT-B to measure cognitive flexibility, and it underscores the need for additional research on the association between cognitive flexibility and the frontal lobes. Further work in a larger sample, including left frontal lobe damage and with more power to detect effects of right posterior brain injury, is necessary to determine whether our observation is specific for right frontal lesions.

  20. Errors on the Trail Making Test Are Associated with Right Hemispheric Frontal Lobe Damage in Stroke Patients.

    Science.gov (United States)

    Kopp, Bruno; Rösser, Nina; Tabeling, Sandra; Stürenburg, Hans Jörg; de Haan, Bianca; Karnath, Hans-Otto; Wessel, Karl

    2015-01-01

    Measures of performance on the Trail Making Test (TMT) are among the most popular neuropsychological assessment techniques. Completion time on TMT-A is considered to provide a measure of processing speed, whereas completion time on TMT-B is considered to constitute a behavioral measure of the ability to shift between cognitive sets (cognitive flexibility), commonly attributed to the frontal lobes. However, empirical evidence linking performance on the TMT-B to localized frontal lesions is mostly lacking. Here, we examined the association of frontal lesions following stroke with TMT-B performance measures (i.e., completion time and completion accuracy measures) using voxel-based lesion-behavior mapping, with a focus on right hemispheric frontal lobe lesions. Our results suggest that the number of errors, but not completion time on the TMT-B, is associated with right hemispheric frontal lesions. This finding contradicts common clinical practice-the use of completion time on the TMT-B to measure cognitive flexibility, and it underscores the need for additional research on the association between cognitive flexibility and the frontal lobes. Further work in a larger sample, including left frontal lobe damage and with more power to detect effects of right posterior brain injury, is necessary to determine whether our observation is specific for right frontal lesions.

  1. Left hemisphere structural connectivity abnormality in pediatric hydrocephalus patients following surgery

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    Weihong Yuan

    2016-01-01

    Full Text Available Neuroimaging research in surgically treated pediatric hydrocephalus patients remains challenging due to the artifact caused by programmable shunt. Our previous study has demonstrated significant alterations in the whole brain white matter structural connectivity based on diffusion tensor imaging (DTI and graph theoretical analysis in children with hydrocephalus prior to surgery or in surgically treated children without programmable shunts. This study seeks to investigate the impact of brain injury on the topological features in the left hemisphere, contratelateral to the shunt placement, which will avoid the influence of shunt artifacts and makes further group comparisons feasible for children with programmable shunt valves. Three groups of children (34 in the control group, 12 in the 3-month post-surgery group, and 24 in the 12-month post-surgery group, age between 1 and 18 years were included in the study. The structural connectivity data processing and analysis were performed based on DTI and graph theoretical analysis. Specific procedures were revised to include only left brain imaging data in normalization, parcellation, and fiber counting from DTI tractography. Our results showed that, when compared to controls, children with hydrocephalus in both the 3-month and 12-month post-surgery groups had significantly lower normalized clustering coefficient, lower small-worldness, and higher global efficiency (all p < 0.05, corrected. At a regional level, both patient groups showed significant alteration in one or more regional connectivity measures in a series of brain regions in the left hemisphere (8 and 10 regions in the 3-month post-surgery and the 12-month post-surgery group, respectively, all p < 0.05, corrected. No significant correlation was found between any of the global or regional measures and the contemporaneous neuropsychological outcomes [the General Adaptive Composite (GAC from the Adaptive Behavior Assessment System, Second

  2. Augmenting Melodic Intonation Therapy with non-invasive brain stimulation to treat impaired left-hemisphere function: two case studies

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    Shahd eAl-Janabi

    2014-02-01

    Full Text Available The purpose of this study was to investigate whether or not the right hemisphere can be engaged using Melodic Intonation Therapy (MIT and excitatory repetitive transcranial magnetic stimulation (rTMS to improve language function in people with aphasia. The two participants in this study (GOE and AMC have chronic non-fluent aphasia. A functional Magnetic Resonance Imaging (fMRI task was used to localize the right Broca’s homologue area in the inferior frontal gyrus for rTMS coil placement. The treatment protocol included an rTMS phase, which consisted of 3 treatment sessions that used an excitatory stimulation method known as intermittent theta burst stimulation, and a sham-rTMS phase, which consisted of 3 treatment sessions that used a sham coil. Each treatment session was followed by 40 minutes of MIT. A linguistic battery was administered after each session. Our findings show that one participant, GOE, improved in verbal fluency and the repetition of phrases treated with MIT in combination with TMS. However, AMC showed no evidence of behavioural benefit from this brief treatment trial. Post-treatment neural activity changes were observed for both participants in the left Broca’s area and right Broca’s homologue. These case studies indicate that a combination of rTMS applied to the right Broca’s homologue and MIT has the potential to improve speech and language outcomes for at least some people with post-stroke aphasia.

  3. Augmenting melodic intonation therapy with non-invasive brain stimulation to treat impaired left-hemisphere function: two case studies.

    Science.gov (United States)

    Al-Janabi, Shahd; Nickels, Lyndsey A; Sowman, Paul F; Burianová, Hana; Merrett, Dawn L; Thompson, William F

    2014-01-01

    The purpose of this study was to investigate whether or not the right hemisphere can be engaged using Melodic Intonation Therapy (MIT) and excitatory repetitive transcranial magnetic stimulation (rTMS) to improve language function in people with aphasia. The two participants in this study (GOE and AMC) have chronic non-fluent aphasia. A functional Magnetic Resonance Imaging (fMRI) task was used to localize the right Broca's homolog area in the inferior frontal gyrus for rTMS coil placement. The treatment protocol included an rTMS phase, which consisted of 3 treatment sessions that used an excitatory stimulation method known as intermittent theta burst stimulation, and a sham-rTMS phase, which consisted of 3 treatment sessions that used a sham coil. Each treatment session was followed by 40 min of MIT. A linguistic battery was administered after each session. Our findings show that one participant, GOE, improved in verbal fluency and the repetition of phrases when treated with MIT in combination with TMS. However, AMC showed no evidence of behavioral benefit from this brief treatment trial. Post-treatment neural activity changes were observed for both participants in the left Broca's area and right Broca's homolog. These case studies indicate that a combination of MIT and rTMS applied to the right Broca's homolog has the potential to improve speech and language outcomes for at least some people with post-stroke aphasia.

  4. Early left-hemispheric dysfunction of face processing in congenital prosopagnosia: an MEG study.

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    Christian Dobel

    Full Text Available BACKGROUND: Congenital prosopagnosia is a severe face perception impairment which is not acquired by a brain lesion and is presumably present from birth. It manifests mostly by an inability to recognise familiar persons. Electrophysiological research has demonstrated the relevance to face processing of a negative deflection peaking around 170 ms, labelled accordingly as N170 in the electroencephalogram (EEG and M170 in magnetoencephalography (MEG. The M170 was shown to be sensitive to the inversion of faces and to familiarity--two factors that are assumed to be crucial for congenital prosopagnosia. In order to locate the cognitive dysfunction and its neural correlates, we investigated the time course of neural activity in response to these manipulations. METHODOLOGY: Seven individuals with congenital prosopagnosia and seven matched controls participated in the experiment. To explore brain activity with high accuracy in time, we recorded evoked magnetic fields (275 channel whole head MEG while participants were looking at faces differing in familiarity (famous vs. unknown and orientation (upright vs. inverted. The underlying neural sources were estimated by means of the least square minimum-norm-estimation (L2-MNE approach. PRINCIPAL FINDINGS: The behavioural data corroborate earlier findings on impaired configural processing in congenital prosopagnosia. For the M170, the overall results replicated earlier findings, with larger occipito-temporal brain responses to inverted than upright faces, and more right- than left-hemispheric activity. Compared to controls, participants with congenital prosopagnosia displayed a general decrease in brain activity, primarily over left occipitotemporal areas. This attenuation did not interact with familiarity or orientation. CONCLUSIONS: The study substantiates the finding of an early involvement of the left hemisphere in symptoms of prosopagnosia. This might be related to an efficient and overused featural

  5. Role of dopamine on functional recovery in the contralateral hemisphere after focal stroke in the somatosensory cortex.

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    Obi, Kisho; Amano, Izuki; Takatsuru, Yusuke

    2018-01-01

    Functional recovery after a stroke is important for patients' quality of life. Not only medical care during the acute phase, but also rehabilitation during the chronic phase after a stroke is important. However, the mechanisms underlying functional recovery, particularly the chronic phase after stroke, are still not fully understood. Thus, further basic study on brain after focal stroke is necessary. In this study, we found that the concentration of dopamine (DA) increased during first week after a stroke in the hemisphere contralateral in the site of stroke by in vivo microdialysis. When we applied haloperidol (HPD), a potent DA receptor blocker, functional recovery was inhibited. Interestingly, administration of aripiprazole (ARP), a novel partial agonist of the DA receptor, during the chronic phase improved the remodeling of neuronal circuits in somatosensory cortex (SSC). These findings indicate that the DAergic system play a critical role in functional compensation by the non-infarcted hemisphere after a focal stroke in SSC. It is also revealed that administration of HPD/ARP to stroke patients affects functional recovery after a stroke, and stimulation of the DAergic system during the chronic phase of stroke potentially benefits stroke patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Theories of inter-hemispheric interactions in aphasia: the role of tDCS in rehabilitation of post-stroke aphasia

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    Roy H Hamilton

    2014-04-01

    Full Text Available Mounting data from behavioral and neuroimaging studies have shown that the process of recovery from aphasia is largely driven by the reorganization of brain networks related to language. Evidence implicates a variety of potential mechanisms in this reorganization, some of which involve substantive changes in brain functional activity within and between cerebral hemispheres. These changes include intrahemispheric recruitment of perilesional left-hemisphere regions and transcallosal interhemispheric interactions between lesioned left-hemisphere language areas and homologous regions in the right hemisphere. With respect to the role of the right hemisphere, it is debated whether interhemispheric interactions are beneficial or deleterious to recovering language networks. Recent years have also seen the emergence of noninvasive brain stimulation techniques such as transcranial magnetic stimulation (TMS and transcranial direct current stimulation (tDCS as potential novel treatments for post-stroke aphasia. Because these techniques are predicated on either focal excitation or inhibition of brain areas, characterization of the functional roles of the left and right hemispheres and transcallosal interactions in aphasia recovery is of central importance to the development and refinement of stimulation-based therapies. However, most treatment studies involving noninvasive brain stimulation in aphasia have tacitly accepted the interhemispheric inhibition model, in which right hemisphere activity interferes with language recovery that is mediated by left hemisphere perisylvian regions. Based on this account, many studies in aphasia involving TMS and tDCS have adopted one of two approaches consistent with the model: left hemisphere excitation or right hemisphere inhibition. In this presentation, we will review both clinical and cognitive neuroscience evidence that elucidates different hemispheric mechanisms that influence recovery from aphasia after stroke

  7. Cerebral hemispheric blood flow velocity differences in left- and right- handers: functional trans-cranial Doppler ultrasonography

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    Sikaroodi H

    2009-12-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: It is a well known fact that language functions are primarily related to the left hemisphere in right handed individuals, there is still no agreement about hemispheric language dominance in left handers. The aim of this study is to evaluate the possibility of using functional Transcranial Doppler ultra sonography (TCD, as a non-invasive method for investigation of hemispheric language dominance and also to explore possible gender influence on hemispheric language representation."n"nMethods: We performed functional TCD during a word generation task, in 62 healthy volunteers (30 right handers and 32 left handers, 50% male and 50% female. All subjects were medical students in the age range of 22-29 years. Right or left handedness was determined using Edinburgh questionnaire. Two subjects were excluded from the study because of poor temporal windows. Mean blood flow velocity was measured in both right and left middle cerebral arteries (MCA at rest and during a word generation task, and changes in flow velocities were compared."n"nResults: Increase of MCA blood flow velocity was observed in 55% (33 subjects of the students in the left side, and in 45% (27 subjects of them in the right side. Right hemispheric

  8. Greater left cerebral hemispheric metabolism in bulimia assessed by positron emission tomography

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    Wu, J.C.; Hagman, J.; Buchsbaum, M.S.; Blinder, B.; Derrfler, M.; Tai, W.Y.; Hazlett, E.; Sicotte, N. (Univ. of California, Irvine (USA))

    1990-03-01

    Eight women with bulimia and eight age- and sex-matched normal control subjects were studied with positron emission tomography using (18F)-fluorodeoxyglucose (FDG) as a tracer of brain metabolic rate. Subjects performed a visual vigilance task during FDG uptake. In control subjects, the metabolic rate was higher in the right hemisphere than in the left, but patients with bulimia did not have this normal asymmetry. Lower metabolic rates in the basal ganglia, found in studies of depressed subjects, and higher rates in the basal ganglia, reported in a study of anorexia nervosa, were not found. This is consistent with the suggestion that bulimia is a diagnostic grouping distinct from these disorders.

  9. Left-hemisphere activation is associated with enhanced vocal pitch error detection in musicians with absolute pitch.

    Science.gov (United States)

    Behroozmand, Roozbeh; Ibrahim, Nadine; Korzyukov, Oleg; Robin, Donald A; Larson, Charles R

    2014-02-01

    The ability to process auditory feedback for vocal pitch control is crucial during speaking and singing. Previous studies have suggested that musicians with absolute pitch (AP) develop specialized left-hemisphere mechanisms for pitch processing. The present study adopted an auditory feedback pitch perturbation paradigm combined with ERP recordings to test the hypothesis whether the neural mechanisms of the left-hemisphere enhance vocal pitch error detection and control in AP musicians compared with relative pitch (RP) musicians and non-musicians (NM). Results showed a stronger N1 response to pitch-shifted voice feedback in the right-hemisphere for both AP and RP musicians compared with the NM group. However, the left-hemisphere P2 component activation was greater in AP and RP musicians compared with NMs and also for the AP compared with RP musicians. The NM group was slower in generating compensatory vocal reactions to feedback pitch perturbation compared with musicians, and they failed to re-adjust their vocal pitch after the feedback perturbation was removed. These findings suggest that in the earlier stages of cortical neural processing, the right hemisphere is more active in musicians for detecting pitch changes in voice feedback. In the later stages, the left-hemisphere is more active during the processing of auditory feedback for vocal motor control and seems to involve specialized mechanisms that facilitate pitch processing in the AP compared with RP musicians. These findings indicate that the left hemisphere mechanisms of AP ability are associated with improved auditory feedback pitch processing during vocal pitch control in tasks such as speaking or singing. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Left hemisphere structural connectivity abnormality in pediatric hydrocephalus patients following surgery.

    Science.gov (United States)

    Yuan, Weihong; Meller, Artur; Shimony, Joshua S; Nash, Tiffany; Jones, Blaise V; Holland, Scott K; Altaye, Mekibib; Barnard, Holly; Phillips, Jannel; Powell, Stephanie; McKinstry, Robert C; Limbrick, David D; Rajagopal, Akila; Mangano, Francesco T

    2016-01-01

    Neuroimaging research in surgically treated pediatric hydrocephalus patients remains challenging due to the artifact caused by programmable shunt. Our previous study has demonstrated significant alterations in the whole brain white matter structural connectivity based on diffusion tensor imaging (DTI) and graph theoretical analysis in children with hydrocephalus prior to surgery or in surgically treated children without programmable shunts. This study seeks to investigate the impact of brain injury on the topological features in the left hemisphere, contratelateral to the shunt placement, which will avoid the influence of shunt artifacts and makes further group comparisons feasible for children with programmable shunt valves. Three groups of children (34 in the control group, 12 in the 3-month post-surgery group, and 24 in the 12-month post-surgery group, age between 1 and 18 years) were included in the study. The structural connectivity data processing and analysis were performed based on DTI and graph theoretical analysis. Specific procedures were revised to include only left brain imaging data in normalization, parcellation, and fiber counting from DTI tractography. Our results showed that, when compared to controls, children with hydrocephalus in both the 3-month and 12-month post-surgery groups had significantly lower normalized clustering coefficient, lower small-worldness, and higher global efficiency (all p  hydrocephalus surgically treated with programmable shunts.

  11. Cognitive outcome after awake surgery for left and right hemisphere tumours

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    Elke De Witte

    2015-04-01

    Full Text Available INTRODUCTION: Awake surgery in eloquent brain regions is performed to preserve language and other cognitive functions. Although in general, no major permanent cognitive deficits are found after awake brain surgery, clinically relevant impairments are detected and cognitive recovery takes longer than generally assumed (3 months (Santini et al., 2012; Satoer et al., 2014; Talacchi et al., 2012. However, as there is a lack of extensive cognitive follow-up data it is unknown when recovery takes place. In addition, the influence of critical language sites identified by direct electrical stimulation (DES and tumour variables (e.g. left/right tumour location, tumour grade on long-term cognitive findings remains unclear. METHODS: In this longitudinal study the short-term and long-term effects of awake surgery on cognition were investigated in 40 patients (29 patients with left and 11 with right hemisphere tumours. Language, memory, attentional, executive and visuospatial functions were assessed in the preoperative phase, at short-term follow-up (6 weeks postsurgery and at long-term follow-up (6 months postsurgery with a neuropsychological protocol. In addition, the effect of intraoperative critical language sites, left/right tumour location, hemispheric language dominance, extent of resection and adjuvant treatment on cognitive change was studied. RESULTS: Both pre- and postoperatively, the mean performance of the patients was worse (impairment = z-score below -2 than the performance of the normal population in the language domain, the memory domain, the attentional and executive domain (p .05. Awake surgery negatively affected language, attentional and executive functions but not memory and visuospatial functions. At 6 weeks postsurgery, performance on all language, attentional and executive tasks deteriorated (object/action naming, semantic/phonological fluency from DuLIP, Token test; Trail Making Test A & B, Stroop I, II, & III. At 6 months

  12. A comparison of hemisphere-specific training pattern in Inter-limb Learning Transfer (ILT) for stroke patients with hemiparesis.

    Science.gov (United States)

    Yoo, In-gyu; Jung, Min-ye; Yoo, Eun-young; Park, Ji-hyuk; Kang, Dae-hyuk; Lee, Jin

    2014-01-01

    Stroke patients have major problems with impaired upper-extremity function. Unfortunately, many patients do not experience a full recovery from movement deficits in the upper extremities. The purpose of this study was to compare the effectiveness of inter-limb learning transfer (ILT) to the contralateral upper limb after both hemisphere-specific and -unspecific ipsilateral upper limb training for stroke patients with hemiparesis. Twenty-four stroke patients with hemiparesis participated. The hemisphere-specific training group performed reaching movements in a customized training setting in which non-dominant limb training participants began from a single starting location and proceeded to one of three target locations (1S3T condition); the dominant limb training participants started from one of three starting locations and proceeded to a single target location (3S1T condition). The hemisphere-unspecific training group performed these movements starting under reverse-start and target conditions. The non-dominant to dominant limb transfer, the hemisphere-specific training group performance time decreased significantly as compared with the pre-training session (p training session in the biceps brachii muscles and increased significantly in the upper trapezius muscles (p transfer in the hemisphere-specific training group significantly increased RMS amplitudes from the pre-training session in the biceps brachii and triceps muscles (p training session in the biceps brachii muscles and decreased significantly in the upper trapezius muscles (p training group showed no significant differences in inter-limb learning transfer (ILT). The transfer of hemisphere-specific training from one arm to the other had a more positive influence on functional recovery than did hemisphere-unspecific training for patients with stroke and hemiparesis.

  13. Ischemic Stroke in a Young Patient Heralding a Left Ventricular Noncompaction Cardiomyopathy

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    Fanny Lestienne

    2017-08-01

    Full Text Available Strokes in young patients may be the clinical expression of many complex and extremely rare diseases. Uncommon causes constitute less than 5% of all strokes, but are present in 30% of strokes in young patients. We report the case of a young woman whose ischemic stroke led to the diagnosis of a rare embolic cardiomyopathy, left ventricular noncompaction cardiomyopathy, requiring a heart transplant.

  14. Case Study of physioterapy treatment of a patient after hemoragic stroke with left hemiparesis

    OpenAIRE

    Formánková, Dita

    2012-01-01

    Title: Case study of physioterapy treatment of a patient after hemoragic stroke with left hemiparesis. Objectives: The aim of the thesis is to obtain academic findings about stroke concerning anatomy, pathology, therapetuic approaches and methods which can be utilised in cases of stroke. The specific part focuses on the therapeutic care of a patient after hemorragic stroke which was taken during a month practice at Rehabilitation clinic Malvazinky, Medditera s.r.o. Summary: The theory of the ...

  15. Case study of physioterapy treatment of patient after hemoragic stroke with left hemiparesis

    OpenAIRE

    Waldmann, Tadeáš

    2014-01-01

    Title: Case study of physioterapy treatment of a patient after hemoragic stroke with left hemiparesis. Objectives: The aim of the thesis is to obtain academic findings about stroke concerning anatomy, pathology, therapetuic approaches and methods which can be utilised in cases of stroke. The specific part focuses on the therapeutic care of a patient after hemorragic stroke which was taken during a month practice at Regional hospital Kladno Spa Summary: The theory of the thesis discusses anato...

  16. Differential white matter involvement associated with distinct visuospatial deficits after right hemisphere stroke.

    Science.gov (United States)

    Carter, Alex R; McAvoy, Mark P; Siegel, Joshua S; Hong, Xin; Astafiev, Serguei V; Rengachary, Jennifer; Zinn, Kristi; Metcalf, Nicholas V; Shulman, Gordon L; Corbetta, Maurizio

    2017-03-01

    Visuospatial attention depends on the integration of multiple processes, and people with right hemisphere lesions after a stroke may exhibit severe or no visuospatial deficits. The anatomy of core components of visuospatial attention is an area of intense interest. Here we examine the relationship between the disruption of core components of attention and lesion distribution in a heterogeneous group (N = 70) of patients with right hemisphere strokes regardless of the presence of clinical neglect. Deficits of lateralized spatial orienting, measured as the difference in reaction times for responding to visual targets in the contralesional or ipsilesional visual field, and deficits in re-orienting attention, as measured by the difference in reaction times for invalidly versus validly cued targets, were measured using a computerized spatial orienting task. Both measures were related through logistic regression and a novel ridge regression method to anatomical damage measured with magnetic resonance imaging. While many regions were common to both deficit maps, a deficit in lateralized spatial orienting was more associated with lesions in the white matter underlying the posterior parietal cortex, and middle and inferior frontal gyri. A deficit in re-orienting of attention toward unattended locations was associated with lesions in the white matter of the posterior parietal cortex, insular cortex and less so with white matter involvement of the anterior frontal lobe. An hodological analysis also supports this partial dissociation between the white matter tracts that are damaged in lateralized spatial biases versus impaired re-orienting. Our results underscore that the integrity of fronto-parietal white matter tracts is crucial for visuospatial attention and that different attention components are mediated by partially distinct neuronal substrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Disorganized behavior on Link's cube test is sensitive to right hemispheric frontal lobe damage in stroke patients

    Science.gov (United States)

    Kopp, Bruno; Rösser, Nina; Tabeling, Sandra; Stürenburg, Hans Jörg; de Haan, Bianca; Karnath, Hans-Otto; Wessel, Karl

    2014-01-01

    One of Luria's favorite neuropsychological tasks for challenging frontal lobe functions was Link's cube test (LCT). The LCT is a cube construction task in which the subject must assemble 27 small cubes into one large cube in such a manner that only the painted surfaces of the small cubes are visible. We computed two new LCT composite scores, the constructive plan composite score, reflecting the capability to envisage a cubical-shaped volume, and the behavioral (dis-) organization composite score, reflecting the goal-directedness of cube construction. Voxel-based lesion-behavior mapping (VLBM) was used to test the relationship between performance on the LCT and brain injury in a sample of stroke patients with right hemisphere damage (N = 32), concentrated in the frontal lobe. We observed a relationship between the measure of behavioral (dis-) organization on the LCT and right frontal lesions. Further work in a larger sample, including left frontal lobe damage and with more power to detect effects of right posterior brain injury, is necessary to determine whether this observation is specific for right frontal lesions. PMID:24596552

  18. Asymmetry of temporal auditory T-complex: right ear-left hemisphere advantage in Tb timing in children.

    Science.gov (United States)

    Bruneau, Nicole; Bidet-Caulet, Aurélie; Roux, Sylvie; Bonnet-Brilhault, Frédérique; Gomot, Marie

    2015-02-01

    To investigate brain asymmetry of the temporal auditory evoked potentials (T-complex) in response to monaural stimulation in children compared to adults. Ten children (7 to 9 years) and ten young adults participated in the study. All were right-handed. The auditory stimuli used were tones (1100 Hz, 70 dB SPL, 50 ms duration) delivered monaurally (right, left ear) at four different levels of stimulus onset asynchrony (700-1100-1500-3000 ms). Latency and amplitude of responses were measured at left and right temporal sites according to the ear stimulated. Peaks of the three successive deflections (Na-Ta-Tb) of the T-complex were greater in amplitude and better defined in children than in adults. Amplitude measurements in children indicated that Na culminates on the left hemisphere whatever the ear stimulated whereas Ta and Tb culminate on the right hemisphere but for left ear stimuli only. Peak latency displayed different patterns of asymmetry. Na and Ta displayed shorter latencies for contralateral stimulation. The original finding was that Tb peak latency was the shortest at the left temporal site for right ear stimulation in children. Amplitude increased and/or peak latency decreased with increasing SOA, however no interaction effect was found with recording site or with ear stimulated. Our main original result indicates a right ear-left hemisphere timing advantage for Tb peak in children. The Tb peak would therefore be a good candidate as an electrophysiological marker of ear advantage effects during dichotic stimulation and of functional inter-hemisphere interactions and connectivity in children. Copyright © 2014. Published by Elsevier B.V.

  19. You may now kiss the bride: Interpretation of social situations by individuals with right or left hemisphere injury.

    Science.gov (United States)

    Baldo, Juliana V; Kacinik, Natalie A; Moncrief, Amber; Beghin, Francesca; Dronkers, Nina F

    2016-01-08

    While left hemisphere damage (LHD) has been clearly shown to cause a range of language impairments, patients with right hemisphere damage (RHD) also exhibit communication deficits, such as difficulties processing prosody, discourse, and social contexts. In the current study, individuals with RHD and LHD were directly compared on their ability to interpret what a character in a cartoon might be saying or thinking, in order to better understand the relative role of the right and left hemisphere in social communication. The cartoon stimuli were manipulated so as to elicit more or less formulaic responses (e.g., a scene of a couple being married by a priest vs. a scene of two people talking, respectively). Participants' responses were scored by blind raters on how appropriately they captured the gist of the social situation, as well as how formulaic and typical their responses were. Results showed that RHD individuals' responses were rated as significantly less appropriate than controls and were also significantly less typical than controls and individuals with LHD. Individuals with RHD produced a numerically lower proportion of formulaic expressions than controls, but this difference was only a trend. Counter to prediction, the pattern of performance across participant groups was not affected by how constrained/formulaic the social situation was. The current findings expand our understanding of the roles that the right and left hemispheres play in social processing and communication and have implications for the potential treatment of social communication deficits in individuals with RHD. Published by Elsevier Ltd.

  20. A case of expressive-vocal amusia in a right-handed patient with left hemispheric cerebral infarction.

    Science.gov (United States)

    Uetsuki, Shizuka; Kinoshita, Hiroshi; Takahashi, Ryuichi; Obata, Satoshi; Kakigi, Tatsuya; Wada, Yoshiko; Yokoyama, Kazumasa

    2016-03-01

    A 53-year-old right-handed woman had an extensive lesion in the left hemisphere due to an infarction caused by vasospasm secondary to subarachnoid bleeding. She exhibited persistent expressive-vocal amusia with no symptoms of aphasia. Evaluation of the patient's musical competence using the Montreal Battery for Evaluation of Amusia, rhythm reproduction tests, acoustic analysis of pitch upon singing familiar music, Japanese standard language tests, and other detailed clinical examinations revealed that her amusia was more dominantly related to pitch production. The intactness of her speech provided strong evidence that the right hemisphere played a major role in her linguistic processing. Data from functional magnetic resonance imaging while she was singing a familiar song, a scale, and reciting lyrics indicated that perilesional residual activation in the left hemisphere was associated with poor pitch production, while right hemispheric activation was involved in linguistic processing. The localization of infarction more anterior to the left Sylvian fissure might be related to the dominant deficits in expressive aspects of the singing of the patient. Compromised motor programming producing a single tone may have made a major contribution to her poor singing. Imperfect auditory feedback due to borderline perceptual ability or improper audio-motor associations might also have played a role. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Is a lone right hemisphere enough? Neurolinguistic architecture in a case with a very early left hemispherectomy.

    Science.gov (United States)

    Danelli, Laura; Cossu, Giuseppe; Berlingeri, Manuela; Bottini, Gabriella; Sberna, Maurizio; Paulesu, Eraldo

    2013-01-01

    We studied the linguistic profile and neurolinguistic organization of a 14-year-old adolescent (EB) who underwent a left hemispherectomy at the age of 2.5 years. After initial aphasia, his language skills recovered within 2 years, with the exception of some word finding problems. Over the years, the neuropsychological assessments showed that EB's language was near-to-normal, with the exception of lexical competence, which lagged slightly behind for both auditory and written language. Moreover, EB's accuracy and speed in both reading and writing words and non-words were within the normal range, whereas difficulties emerged in reading loan words and in tasks with homophones. EB's functional magnetic resonance imaging (fMRI) patterns for several linguistic and metalinguistic tasks were similar to those observed in the dominant hemisphere of controls, suggesting that his language network conforms to a left-like linguistic neural blueprint. However, a stronger frontal recruitment suggests that linguistic tasks are more demanding for him. Finally, no specific reading activation was found in EB's occipitotemporal region, a finding consistent with the surface dyslexia-like behavioral pattern of the patient. While a lone right hemisphere may not be sufficient to guarantee full blown linguistic competences after early hemispherectomy, EB's behavioral and fMRI patterns suggest that his lone right hemisphere followed a left-like blueprint of the linguistic network.

  2. Cortical activity in the left and right hemispheres during language-related brain functions

    DEFF Research Database (Denmark)

    Lassen, N A; Larsen, B

    1980-01-01

    of cortical activity seen during various language functions, emphasizing the practically symmetrical involvement in both hemispheres. A case of auditive agnosia (with complete cortical word deafness but preserved pure tone thresholds) is presented. The patient's normal speech constitutes evidence...

  3. Electroencephalographic (eeg coherence between visual and motor areas of the left and the right brain hemisphere while performing visuomotor task with the right and the left hand

    Directory of Open Access Journals (Sweden)

    Simon Brežan

    2007-09-01

    Full Text Available Background: Unilateral limb movements are based on the activation of contralateral primary motor cortex and the bilateral activation of premotor cortices. Performance of a visuomotor task requires a visuomotor integration between motor and visual cortical areas. The functional integration (»binding« of different brain areas, is probably mediated by the synchronous neuronal oscillatory activity, which can be determined by electroencephalographic (EEG coherence analysis. We introduced a new method of coherence analysis and compared coherence and power spectra in the left and right hemisphere for the right vs. left hand visuomotor task, hypothesizing that the increase in coherence and decrease in power spectra while performing the task would be greater in the contralateral hemisphere.Methods: We analyzed 6 healthy subjects and recorded their electroencephalogram during visuomotor task with the right or the left hand. For data analysis, a special Matlab computer programme was designed. The results were statistically analysed by a two-way analysis of variance, one-way analysis of variance and post-hoc t-tests with Bonferroni correction.Results: We demonstrated a significant increase in coherence (p < 0.05 for the visuomotor task compared to control tasks in alpha (8–13 Hz in beta 1 (13–20 Hz frequency bands between visual and motor electrodes. There were no significant differences in coherence nor power spectra depending on the hand used. The changes of coherence and power spectra between both hemispheres were symmetrical.Conclusions: In previous studies, a specific increase of coherence and decrease of power spectra for the visuomotor task was found, but we found no conclusive asymmetries when performing the task with right vs. left hand. This could be explained in a way that increases in coherence and decreases of power spectra reflect symmetrical activation and cooperation between more complex visual and motor brain areas.

  4. Neurogenesis upregulation on the healthy hemisphere after stroke enhances compensation for age-dependent decrease of basal neurogenesis.

    Science.gov (United States)

    Adamczak, Joanna; Aswendt, Markus; Kreutzer, Christina; Rotheneichner, Peter; Riou, Adrien; Selt, Marion; Beyrau, Andreas; Uhlenküken, Ulla; Diedenhofen, Michael; Nelles, Melanie; Aigner, Ludwig; Couillard-Despres, Sebastien; Hoehn, Mathias

    2017-03-01

    Stroke is a leading cause of death and disability worldwide with no treatment for the chronic phase available. Interestingly, an endogenous repair program comprising inflammation and neurogenesis is known to modulate stroke outcome. Several studies have shown that neurogenesis decreases with age but the therapeutic importance of endogenous neurogenesis for recovery from cerebral diseases has been indicated as its ablation leads to stroke aggravation and worsened outcome. A detailed characterization of the neurogenic response after stroke related to ageing would help to develop novel and targeted therapies. In an innovative approach, we used the DCX-Luc mouse, a transgenic model expressing luciferase in doublecortin-positive neuroblasts, to monitor the neurogenic response following middle cerebral artery occlusion over three weeks in three age groups (2, 6, 12months) by optical imaging while the stroke lesion was monitored by quantitative MRI. The individual longitudinal and noninvasive time profiles provided exclusive insight into age-dependent decrease in basal neurogenesis and neurogenic upregulation in response to stroke which are not accessible by conventional BrdU-based measures of cell proliferation. For cortico-striatal strokes the maximal upregulation occurred at 4days post stroke followed by a continuous decrease to basal levels by three weeks post stroke. Older animals effectively compensated for reduced basal neurogenesis by an enhanced sensitivity to the cerebral lesion, resulting in upregulated neurogenesis levels approaching those measured in young mice. In middle aged and older mice, but not in the youngest ones, additional upregulation of neurogenesis was observed in the contralateral healthy hemisphere. This further substantiates the increased propensity of older brains to respond to lesion situation. Our results clearly support the therapeutic relevance of endogenous neurogenesis for stroke recovery and particularly in older brains. Copyright

  5. The application of SHERPA (Systematic Human Error Reduction and Prediction Approach) in the development of compensatory cognitive rehabilitation strategies for stroke patients with left and right brain damage.

    Science.gov (United States)

    Hughes, Charmayne M L; Baber, Chris; Bienkiewicz, Marta; Worthington, Andrew; Hazell, Alexa; Hermsdörfer, Joachim

    2015-01-01

    Approximately 33% of stroke patients have difficulty performing activities of daily living, often committing errors during the planning and execution of such activities. The objective of this study was to evaluate the ability of the human error identification (HEI) technique SHERPA (Systematic Human Error Reduction and Prediction Approach) to predict errors during the performance of daily activities in stroke patients with left and right hemisphere lesions. Using SHERPA we successfully predicted 36 of the 38 observed errors, with analysis indicating that the proportion of predicted and observed errors was similar for all sub-tasks and severity levels. HEI results were used to develop compensatory cognitive strategies that clinicians could employ to reduce or prevent errors from occurring. This study provides evidence for the reliability and validity of SHERPA in the design of cognitive rehabilitation strategies in stroke populations.

  6. Percutaneous left atrial appendage closure for stroke prevention

    DEFF Research Database (Denmark)

    De Backer, Ole; Loupis, Anastasia M; Ihlemann, Nikolaj

    2014-01-01

    as an alternative option for stroke prevention in AF patients with contraindication(s) for OAC treatment. MATERIAL AND METHODS: A total of 42 patients underwent percutaneous LAA closure. In this report, we describe our experience with this procedure. RESULTS: The patients treated were AF patients with a high stroke...... and bleeding risk. However, long-term follow-up studies are needed before this procedure can be recommended for routine clinical use. FUNDING: Grant funding was received (St Jude Medical) for research, but there are no other competing interests. TRIAL REGISTRATION: Not relevant....

  7. Embedded Words in Visual Word Recognition: Does the Left Hemisphere See the Rain in Brain?

    Science.gov (United States)

    McCormick, Samantha F.; Davis, Colin J.; Brysbaert, Marc

    2010-01-01

    To examine whether interhemispheric transfer during foveal word recognition entails a discontinuity between the information presented to the left and right of fixation, we presented target words in such a way that participants fixated immediately left or right of an embedded word (as in "gr*apple", "bull*et") or in the middle…

  8. The left atrial septal pouch as a risk factor for stroke: A systematic review.

    Science.gov (United States)

    Strachinaru, Mihai; Castro-Rodriguez, Jose; Verbeet, Thierry; Gazagnes, Marie-Dominique

    2017-04-01

    The left atrial septal pouch (LASP) is formed by incomplete fusion of the septum primum and septum secundum, leaving a cavity open towards the left atrium, but without interatrial shunting. There is no recommendation concerning strategy in the presence of a LASP, especially in the setting of stroke. The aim of this review was to determine whether the LASP could be incriminated as the aetiology of a stroke. We included all pertinent publications on the subject, and calculated hazard ratios for ischaemic stroke and cryptogenic stroke. There were only five case-control studies concerning the LASP, involving 516 stroke patients and 779 controls. Overall LASP prevalence was 21%, with a slightly higher prevalence in the cryptogenic stroke group (26%), but this difference was not statistically significant (P=0.27). In a random-effects meta-analysis, there was no difference between controls and patients with ischaemic stroke (hazard ratio 1.20, 95% confidence interval 0.96-1.53; P=0.14). Cryptogenic stroke appeared more frequently in patients with LASP (hazard ratio 1.53, 95% confidence interval 1.07-2.24; P=0.02), but this was driven by only one severely underpowered study. The published case reports demonstrated that thrombus formation inside the pouch can occur in the presence of major predisposing factors. The LASP can be a site for thrombus formation, leading to embolic events, but its presence does not correlate with an increased incidence of stroke. Associated factors should be taken into consideration in the setting of stroke. Further studies are necessary to validate a possible relationship with cryptogenic stroke. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  9. Giant left atrial myxoma causing acute ischemic stroke in a child

    OpenAIRE

    Ise, Hayato; Ishikawa, Natsuya; Nakanishi, Sentaro; Kamiya, Hiroyuki

    2018-01-01

    Ischemic stroke is uncommon in pediatric populations and is sometimes caused by cardiac myxoma. In such cases, neurological deficits initially present in ischemic stroke due to emboli or thrombi of the myxoma. Echocardiography is helpful to diagnose myxoma in a timely manner and allows urgent surgical resection of the myxoma. We report a successful case of myxoma in a 7-year-old boy who initially presented with left-sided hemiparesis.

  10. Percutaneous left atrial appendage closure for stroke prevention

    DEFF Research Database (Denmark)

    De Backer, Ole; Loupis, Anastasia M; Ihlemann, Nikolaj

    2014-01-01

    risk (CHADS-VASc 4.5±1.4) and contra-indication(s) for OAC and/or a high bleeding risk (HAS-BLED 3.7±0.9). A history of intracerebral bleeding was the most common reason for LAA closure. Successful implantation was obtained in 41 of 42 patients. One major peri-procedural complication occurred; a major...... gastrointestinal bleeding immediately after the procedure. The mean duration of follow-up was 12.6 months. Both ischaemic stroke and bleeding occurred in one patient, resulting in an observed annual stroke and bleeding rate of 2.3%. This rate was lower than expected based on the CHADS-VASc (5.6%/year) and HAS...

  11. Electrophysiological evidence for the action of a center-surround mechanism on semantic processing in the left hemisphere

    Directory of Open Access Journals (Sweden)

    Diana eDeacon

    2013-12-01

    Full Text Available Physiological evidence was sought for a center-surround attentional mechanism (CSM, which has been proposed to assist in the retrieval of weakly activated items from semantic memory. The CSM operates by facilitating strongly related items in the center of the weakly activated area of semantic memory, and inhibiting less strongly related items in its surround. In this study weak activation was created by having subjects acquire the meanings of new words to a recall criterion of only 50%. Subjects who attained this approximate criterion level of performance were subsequently included in a semantic priming task, during which ERPs were recorded. Primes were newly learned rare words, and targets were either synonyms, nonsynonymously related words, or unrelated words. All stimuli were presented to the RVF/LH (right visual field/left hemisphere or the LVF/RH (left visual field/right hemisphere. Under RVF/LH stimulation the newly learned word primes produced facilitation on N400 for synonym targets, and inhibition for related targets. No differences were observed under LVF/RH stimulation. The LH thus, supports a CSM, whereby a synonym in the center of attention focused on the newly learned word is facilitated, whereas a related word in the surround is inhibited. The data are consistent with the view of this laboratory that semantic memory is subserved by a spreading activation system in the LH. Also consistent with our view, there was no evidence of spreading activation in the RH. The findings are discussed in the context of additional recent theories of semantic memory. Finally, the adult right hemisphere may require more learning than the LH in order to demonstrate evidence of meaning acquisition.

  12. Left-hand somatosensory stimulation combined with visual scanning training in rehabilitation for post-stroke hemineglect: a randomised, double-blind study.

    Science.gov (United States)

    Polanowska, Katarzyna; Seniów, Joanna; Paprot, Ewa; Leśniak, Marcin; Członkowska, Anna

    2009-06-01

    The aim of this randomised, double-blind study was to investigate the therapeutic effectiveness of left-hand electrical stimulation for patients with post-stroke left visuo-spatial neglect. This approach was hypothesised to enhance activation of the right hemisphere attention system and to improve visual exploration of extrapersonal space. Participants (n = 40) in the study were in a relatively early stage of recovery from their first right hemisphere stroke, and were randomly assigned to the experimental (E) or control (C) group. Group E received conventional visual scanning training combined with electrostimulation of the left hand, while Group C received scanning training with sham stimulation. Their visuo-spatial neglect was assessed twice, prior to the rehabilitation programme and on its completion, using cancellation tests and a letter-reading task. The effect of electrostimulation on hemineglect was assessed following a single administration and after a month-long rehabilitation programme. Although the immediate effect of stimulation was poor, after a month-long rehabilitation period we found significantly greater improvement in Group E patients than in Group C patients. Interestingly, the presence of hemisensory loss did not weaken the observed effect. Therefore, we claim that contralesional hand stimulation combined with visual scanning was a more effective treatment for hemineglect rehabilitation than scanning training alone.

  13. Left inferior frontal gyrus mediates morphosyntax: ERP evidence from verb processing in left-hemisphere damaged patients.

    Science.gov (United States)

    Regel, Stefanie; Kotz, Sonja A; Henseler, Ilona; Friederici, Angela D

    2017-01-01

    Neurocognitive models of language comprehension have proposed different mechanisms with different neural substrates mediating human language processing. Whether the left inferior frontal gyrus (LIFG) is engaged in morpho-syntactic information processing is currently still controversially debated. The present study addresses this issue by examining the processing of irregular verb inflection in real words (e.g., swim > swum > swam) and pseudowords (e.g., frim > frum > fram) by using event-related brain potentials (ERPs) in neurological patients with lesions in the LIFG involving Broca's area as well as healthy controls. Different ERP patterns in response to the grammatical violations were observed in both groups. Controls showed a biphasic negativity-P600 pattern in response to incorrect verb inflections whereas patients with LIFG lesions displayed a N400. For incorrect pseudoword inflections, a late positivity was found in controls, while no ERP effects were obtained in patients. These findings of different ERP patterns in the two groups strongly indicate an involvement of LIFG in morphosyntactic processing, thereby suggesting brain regions' specialization for different language functions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. A tale of two hemispheres: Contrasting socioemotional dysfunction in right- versus left-lateralised semantic dementia

    Directory of Open Access Journals (Sweden)

    Muireann Irish

    Full Text Available ABSTRACT Objective: Semantic dementia, a subtype of frontotemporal lobar degeneration, is characterised by cross-modal loss of conceptual knowledge attributable to progressive degeneration of the left anterior temporal lobe. Much less is known regarding the clinical presentation of SD patients with predominantly right-lateralised atrophy. Recent reports emphasise marked socioemotional and behavioural disturbances in such cases. Given the importance of the right anterior temporal lobes in social cognition, we hypothesised that socioemotional functioning would be disproportionately affected in right versus left-lateralised SD cases. Methods: We assessed well-characterised cases of predominantly right (n=10 and left (n=12 SD and 20 matched healthy controls on tests of emotion processing and interpersonal functioning. Results: Right SD cases showed disproportionate difficulties in the recognition of positive and negative facial emotions, specifically happiness and anger, compared with left SD cases. Deficits in anger recognition persisted in right SD despite covarying for facial and semantic processing. On a contextually rich task of emotion recognition using multimodal videos, no subgroup differences were evident. Finally, empathic concern was rated as significantly lower by caregivers of right versus left SD cases. Overall, the extent of socioemotional disturbance was associated with the degree of behavioural changes in SD. Conclusion: Our results reveal considerable overlap in the extent to which socioemotional processes are disrupted in left and right-lateralised cases of SD. Notably, however, right SD cases show disproportionate deficits for recognition of facial emotions and the capacity for empathic concern, supporting a specialised role for the right anterior temporal lobes in mediating these cognitive functions.

  15. Improved Spatial Ability Correlated with Left Hemisphere Dysfunction in Turner's Syndrome. Implications for Mechanism.

    Science.gov (United States)

    Rovet, Joanne F.

    This study contrasts the performance of a 17-year-old female subject with Turner's syndrome before and after developing left temporal lobe seizures, as a means of identifying the mechanism responsible for the Turner's syndrome spatial impairment. The results revealed a deficit in spatial processing before onset of the seizure disorder. Results…

  16. Right-hemispheric processing of non-linguistic word features

    DEFF Research Database (Denmark)

    Baumgaertner, Annette; Hartwigsen, Gesa; Roman Siebner, Hartwig

    2013-01-01

    -hemispheric homologues of classic left-hemispheric language areas may partly be due to processing nonlinguistic perceptual features of verbal stimuli. We used functional MRI (fMRI) to clarify the role of the right hemisphere in the perception of nonlinguistic word features in healthy individuals. Participants made......, in some instances, be driven by a "nonlinguistic perceptual processing" mode that focuses on nonlinguistic word features. This raises the possibility that stronger activation of right inferior frontal areas during language tasks in aphasic patients with left-hemispheric stroke may at least partially...

  17. Lateralization of brain activation to imagination and smell of odors using functional magnetic resonance imaging (fMRI): left hemispheric localization of pleasant and right hemispheric localization of unpleasant odors.

    Science.gov (United States)

    Henkin, R I; Levy, L M

    2001-01-01

    Our goal was to use functional MRI (fMRI) of brain to reveal activation in each cerebral hemisphere in response to imagination and smell of odors. FMRI brain scans were obtained in 24 normal subjects using multislice fast low angle shot (FLASH) MRI in response to imagination of banana and peppermint odors and in response to smell of corresponding odors of amyl acetate and menthone, respectively, and of pyridine. Three coronal sections selected from anterior to posterior brain regions were used. Similar studies were obtained in two patients with hyposmia using FLASH MRI and in one patient with hyposmia using echo planar imaging (EPI) both before and after theophylline treatment that returned smell function to or toward normal in each patient and in two patients with birhinal phantosmia (persistent foul odor) and global phantogeusia (persistent foul taste) with FLASH and EPI fMRI before and after treatment with neuroleptic drugs that inhibited their phantosmia and phantogeusia. Activation images were derived using correlation analysis. Ratios of hemispheric areas of brain activation to total hemispheric brain areas were calculated for FLASH fMRI, and numerical counts of pixel clusters in each hemisphere were made for EPI studies. Total pixel cluster counts in localized regions of each hemispheric section were also obtained. In normal subjects, activation generally occurred in left (L) > right (R) brain hemisphere in response to banana and peppermint odor imagination and to smell of corresponding odors of amyl acetate and menthone. Whereas there were no overall hemispheric differences for pyridine odor, activation in men was R > L hemisphere. Although absolute activation in both L and R hemispheres in response to banana odor imagination and amyl acetate smell was men > women, the ratio of L to R activation was women > men. In hyposmic patients studied by FLASH fMRI, activation to banana odor imagination and amyl acetate smell was L > R hemisphere both before and after

  18. Activity levels in the left hemisphere caudate-fusiform circuit predict how well a second language will be learned.

    Science.gov (United States)

    Tan, Li Hai; Chen, Lin; Yip, Virginia; Chan, Alice H D; Yang, Jing; Gao, Jia-Hong; Siok, Wai Ting

    2011-02-08

    How second language (L2) learning is achieved in the human brain remains one of the fundamental questions of neuroscience and linguistics. Previous neuroimaging studies with bilinguals have consistently shown overlapping cortical organization of the native language (L1) and L2, leading to a prediction that a common neurobiological marker may be responsible for the development of the two languages. Here, by using functional MRI, we show that later skills to read in L2 are predicted by the activity level of the fusiform-caudate circuit in the left hemisphere, which nonetheless is not predictive of the ability to read in the native language. We scanned 10-y-old children while they performed a lexical decision task on L2 (and L1) stimuli. The subjects' written language (reading) skills were behaviorally assessed twice, the first time just before we performed the fMRI scan (time 1 reading) and the second time 1 y later (time 2 reading). A whole-brain based analysis revealed that activity levels in left caudate and left fusiform gyrus correlated with L2 literacy skills at time 1. After controlling for the effects of time 1 reading and nonverbal IQ, or the effect of in-scanner lexical performance, the development in L2 literacy skills (time 2 reading) was also predicted by activity in left caudate and fusiform regions that are thought to mediate language control functions and resolve competition arising from L1 during L2 learning. Our findings suggest that the activity level of left caudate and fusiform regions serves as an important neurobiological marker for predicting accomplishment in reading skills in a new language.

  19. Stroke Laterality Bias in the Management of Acute Ischemic Stroke.

    Science.gov (United States)

    McCluskey, Gavin; Wade, Carrie; McKee, Jacqueline; McCarron, Peter; McVerry, Ferghal; McCarron, Mark O

    2016-11-01

    Little is known of the impact of stroke laterality on the management process and outcome of patients with acute ischemic stroke (AIS). Consecutive patients admitted to a general hospital over 1 year with supratentorial AIS were eligible for inclusion in the study. Baseline characteristics and risk factors, delays in hospital admission, imaging, intrahospital transfer to an acute stoke unit, stroke severity and classification, length of hospital admission, as well as 10-year mortality were measured and compared among right and left hemisphere AIS patients. There were 141 patients (77 men, 64 women; median age 73 [interquartile range 63-79] years), There were 71 patients with left hemisphere AIS and 70 with right hemisphere AIS. Delays to hospital admission from stroke onset to neuroimaging were similar among right and left hemisphere AIS patients. Delay in transfer to an acute stroke unit (ASU) following hospital admission was on average 14 hours more for right hemisphere compared to left hemisphere AIS patients (P = .01). Laterality was not associated with any difference in 10-year survival. Patients with mild and nondominant AIS merit particular attention to minimize their intrahospital transfer time to an ASU. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  20. Functional recovery of gait and joint kinematics after right hemispheric stroke

    NARCIS (Netherlands)

    Huitema, RB; Mulder, T; Brouwer, WH; Dekker, R; Postema, K; Hof, A.L.

    2004-01-01

    Objective: To gain insight into the relation between changes in gait patterns over time and functional recovery of walking ability in stroke patients. Design: Cohort study. Setting: Inpatient rehabilitation center of a university hospital in the Netherlands. Participants: Thirteen stroke patients

  1. Selective attention to phonology dynamically modulates initial encoding of auditory words within the left hemisphere.

    Science.gov (United States)

    Yoncheva, Yuliya; Maurer, Urs; Zevin, Jason D; McCandliss, Bruce D

    2014-08-15

    Selective attention to phonology, i.e., the ability to attend to sub-syllabic units within spoken words, is a critical precursor to literacy acquisition. Recent functional magnetic resonance imaging evidence has demonstrated that a left-lateralized network of frontal, temporal, and posterior language regions, including the visual word form area, supports this skill. The current event-related potential (ERP) study investigated the temporal dynamics of selective attention to phonology during spoken word perception. We tested the hypothesis that selective attention to phonology dynamically modulates stimulus encoding by recruiting left-lateralized processes specifically while the information critical for performance is unfolding. Selective attention to phonology was captured by manipulating listening goals: skilled adult readers attended to either rhyme or melody within auditory stimulus pairs. Each pair superimposed rhyming and melodic information ensuring identical sensory stimulation. Selective attention to phonology produced distinct early and late topographic ERP effects during stimulus encoding. Data-driven source localization analyses revealed that selective attention to phonology led to significantly greater recruitment of left-lateralized posterior and extensive temporal regions, which was notably concurrent with the rhyme-relevant information within the word. Furthermore, selective attention effects were specific to auditory stimulus encoding and not observed in response to cues, arguing against the notion that they reflect sustained task setting. Collectively, these results demonstrate that selective attention to phonology dynamically engages a left-lateralized network during the critical time-period of perception for achieving phonological analysis goals. These findings suggest a key role for selective attention in on-line phonological computations. Furthermore, these findings motivate future research on the role that neural mechanisms of attention may

  2. Interactive virtual environment training for safe street crossing of right hemisphere stroke patients with unilateral spatial neglect.

    Science.gov (United States)

    Katz, N; Ring, H; Naveh, Y; Kizony, R; Feintuch, U; Weiss, P L

    2005-10-30

    The goal of this study was to determine whether non immersive interactive virtual environments are an effective medium for training individuals who suffer from Unilateral Spatial Neglect (USN) as a result of a right hemisphere stroke, and to compare it to a standard computer visual scanning training. Participants included 19 patients with right hemisphere stroke in two groups, 11 in an experimental group were given computer desktop-based Virtual Reality (VR) street crossing training and 8 in a control group who were given computer based visual scanning tasks, both for a total of twelve sessions, 9 hours total, over four weeks. Measures included: 1. Standard USN assessments, paper and pencil and ADL checklist; 2. Test on the VR street program; and 3. Actual street crossing videotaped. Testing was performed pre and post intervention. The VR group achieved on the USN measures results that equaled those achieved by the control group treated with conventional visual scanning tasks. They improved more on the VR test and they did better on some measures of the real street crossing. Despite several limitations in this study the present results support the effectiveness of the VR street program in the treatment of participants with USN, and further development of the program.

  3. Huge Left Ventricular Thrombus and Apical Ballooning associated with Recurrent Massive Strokes in a Septic Shock Patient

    Directory of Open Access Journals (Sweden)

    Hyun-Jung Lee

    2016-02-01

    Full Text Available The most feared complication of left ventricular thrombus (LVT is the occurrence of systemic thromboembolic events, especially in the brain. Herein, we report a patient with severe sepsis who suffered recurrent devastating embolic stroke. Transthoracic echocardiography revealed apical ballooning of the left ventricle with a huge LVT, which had not been observed in chest computed tomography before the stroke. This case emphasizes the importance of serial cardiac evaluation in patients with stroke and severe medical illness.

  4. Hemispheric prevalence during chewing in normal right-handed and left-handed subjects: a functional magnetic resonance imaging preliminary study.

    Science.gov (United States)

    Bracco, Pietro; Anastasi, Giuseppe; Piancino, Maria Grazia; Frongia, Gianluigi; Milardi, Demetrio; Favaloro, Angelo; Bramanti, Placido

    2010-04-01

    This study evaluated the activation of different cortical areas during nondeliberate chewing of soft and hard boluses in five right-handed and five left-handed subjects with normal occlusion, to determine different hemispheric prevalences. The study was conducted with a functional Magnetic Resonance Imaging (1.5 T Magnetom Vision - Siemens Medical, Germany) using a head coil. The results showed that the most frequently activated areas were Brodmann's areas four and six in the primary motor and premotor cortex, the insula and Broca's area and, overall, showed greater activity of the cortical mastication area (CMA) in the right hemisphere for right-handed and in the left hemisphere for left-handed subjects.

  5. Left atrial size in patients with cryptogenic stroke as a predictor of occurrence of atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Antonio Cruz Culebras

    2017-04-01

    Full Text Available Objective: To determine whether the left atrial size can predict the development of atrial fibrillation (AF in patients with embolic stroke of undetermined source (ESUS. Methods: Patients with ischemic stroke were included prospectively (January 2015-July 2015 when ESUS was suspected. Clinical and cardiac imaging data were recorded. Patients with cardiac failure were excluded. Results: a total of 55 patients were included. Medium age was 71 years. The proportion of patients who developed AF during the follow-up (1 year was 23, 63%. 10 % of patients did not have any vascular risk factor. Basal ECG was normal in 98% of cases. The left atrial size volume was 36, 08 ml in patients who developed AF and 27, 14 ml in patients who did not. Conclusions: In patients with ESUS, left atrial size dimensions do not predict the occurrence of AF.

  6. Impairment of language is related to left parieto-temporal glucose metabolism in aphasic stroke patients.

    Science.gov (United States)

    Karbe, H; Szelies, B; Herholz, K; Heiss, W D

    1990-02-01

    Twenty-six aphasic patients who had an ischaemic infarct in the territory of the left middle cerebral artery (MCA) were investigated. Cranial computed tomography (CT) showed various lesion sites: infarcts restricted to cortical structures in 12 patients, combined cortical and subcortical infarcts in 7 and isolated subcortical infarcts sparing the left cortex in another 7 cases. 18F-2-fluoro-2-deoxyglucose positron emission tomography revealed remote hypometabolism of the left convexity cortex and of the left basal ganglia, which was extended further than the morphological infarct zone in all cases. Types and degrees of aphasia were classified using the Aachener Aphasie Test (AAT): 10 patients had global aphasia, 2 Broca's, 5 Wernicke's, and 5 amnesic aphasia. Four patients suffered from minimal or residual aphasic symptoms. The AAT results were compared with the regional cerebral metabolic rates of glucose of the left hemisphere. Irrespective of the infarct location all five AAT subtests (Token test, repetition, written language, confrontation naming, auditory and reading comprehension) were closely correlated among each other and with left parieto-temporal metabolic rates, whereas left frontal and left basal ganglia metabolism showed no significant correlation. The close relation between left temporo-parietal functional activity and all five AAT subtests suggests that the different aspects of aphasia tested by AAT can be related to a common disorder of language processing in those areas.

  7. Non-invasive measurement of stroke volume and left ventricular ejection fraction. Radionuclide cardiography compared with left ventricular cardioangiography

    DEFF Research Database (Denmark)

    Kelbaek, H; Svendsen, Jesper Hastrup; Aldershvile, J

    2011-01-01

    The stroke volume (SV) was determined by first passage radionuclide cardiography and the left ventricular ejection fraction (LVEF) by multigated radionuclide cardiography in 20 patients with ischemic heart disease. The results were evaluated against those obtained by the invasive dye dilution...... or thermodilution and left ventricular cardioangiographic techniques. In a paired comparison the mean difference between the invasive and radionuclide SV was -1 ml (SED 3.1) with a correlation coefficient of 0.83 (p less than 0.01). Radionuclide LVEF values also correlated well with cardioangiographic measurements......, r = 0.93 (p less than 0.001). LVEF determined by multigated radionuclide cardiography was, however, significantly lower than when measured by cardioangiography, the mean difference being 6 per cent (p less than 0.001). These findings suggest that radionuclide determinations of SV and LVEF...

  8. Left Atrial Enlargement on Transthoracic Echocardiography Predicts Left Atrial Thrombus on Transesophageal Echocardiography in Ischemic Stroke Patients

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    James Anaissie

    2016-01-01

    Full Text Available Background. Transesophageal echocardiogram (TEE is superior to transthoracic echocardiogram (TTE in detecting left atrial thrombus (LAT, a risk factor for stroke, but is costly and invasive, carrying a higher risk for complications. Aims. To determine the utility of using left atrial enlargement (LAE on TTE to predict LAT on TEE. Methods. AIS patients who presented in 06/2008–7/2013 and underwent both TTE and TEE were identified from our prospective stroke registry. Analysis consisted of multivariate logistic regression with propensity score adjustment and receiver operating characteristic (ROC area under the curve (AUC analyses. Results. 219 AIS patients underwent both TTE and TEE. LAE on TTE was detected in 113 (51.6% of AIS patients. Patients with LAE on TTE had higher proportion of LAT on TEE (8.4% versus 1.0%, p=0.018. LAE on TTE predicted increased odds of LAT on TEE (OR=8.83, 95% CI 1.04–74.83, p=0.046. The sensitivity and specificity for LAT on TEE by LAE on TEE were 88.89% and 52.20%, respectively (AUC=0.7054, 95% CI 0.5906–0.8202. Conclusions. LAE on TTE can predict LAT detected on TEE in nearly 90% of patients. This demonstrates the utility of LAE on TTE as a potential screening tool for LAT, potentially limiting unneeded costs and complications associated with TEE.

  9. Left Atrial Enlargement on Transthoracic Echocardiography Predicts Left Atrial Thrombus on Transesophageal Echocardiography in Ischemic Stroke Patients.

    Science.gov (United States)

    Anaissie, James; Monlezun, Dominique; Seelochan, A; Siegler, James E; Chavez-Keatts, Maria; Tiu, Jonathan; Pineda, Denise; George, Alexander; Shaban, Amir; Abi Rafeh, Nidal; Schluter, Laurie; Martin-Schild, Sheryl; El Khoury, Ramy

    2016-01-01

    Background. Transesophageal echocardiogram (TEE) is superior to transthoracic echocardiogram (TTE) in detecting left atrial thrombus (LAT), a risk factor for stroke, but is costly and invasive, carrying a higher risk for complications. Aims. To determine the utility of using left atrial enlargement (LAE) on TTE to predict LAT on TEE. Methods. AIS patients who presented in 06/2008-7/2013 and underwent both TTE and TEE were identified from our prospective stroke registry. Analysis consisted of multivariate logistic regression with propensity score adjustment and receiver operating characteristic (ROC) area under the curve (AUC) analyses. Results. 219 AIS patients underwent both TTE and TEE. LAE on TTE was detected in 113 (51.6%) of AIS patients. Patients with LAE on TTE had higher proportion of LAT on TEE (8.4% versus 1.0%, p = 0.018). LAE on TTE predicted increased odds of LAT on TEE (OR = 8.83, 95% CI 1.04-74.83, p = 0.046). The sensitivity and specificity for LAT on TEE by LAE on TEE were 88.89% and 52.20%, respectively (AUC = 0.7054, 95% CI 0.5906-0.8202). Conclusions. LAE on TTE can predict LAT detected on TEE in nearly 90% of patients. This demonstrates the utility of LAE on TTE as a potential screening tool for LAT, potentially limiting unneeded costs and complications associated with TEE.

  10. Another look at category effects on colour perception and their left hemispheric lateralisation: no evidence from a colour identification task.

    Science.gov (United States)

    Suegami, Takashi; Aminihajibashi, Samira; Laeng, Bruno

    2014-05-01

    The present study aimed to replicate category effects on colour perception and their lateralisation to the left cerebral hemisphere (LH). Previous evidence for lateralisation of colour category effects has been obtained with tasks where a differently coloured target was searched within a display and participants reported the lateral location of the target. However, a left/right spatial judgment may yield LH-laterality effects per se. Thus, we employed an identification task that does not require a spatial judgment and used the same colour set that previously revealed LH-lateralised category effects. The identification task was better performed with between-category colours than with within-category task both in terms of accuracy and latency, but such category effects were bilateral or RH-lateralised, and no evidence was found for LH-laterality effects. The accuracy scores, moreover, indicated that the category effects derived from low sensitivities for within-blue colours and did not reflect the effects of categorical structures on colour perception. Furthermore, the classic "category effects" were observed in participants' response biases, instead of sensitivities. The present results argue against both the LH-lateralised category effects on colour perception and the existence of colour category effects per se.

  11. Anosognosia, neglect and quality of life of right hemisphere stroke survivors.

    Science.gov (United States)

    Dai, C-Y; Liu, W-M; Chen, S-W; Yang, C-A; Tung, Y-C; Chou, L-W; Lin, L-C

    2014-05-01

    Anosognosia and neglect may coexist in stroke patients. Neglect patients often report poor quality of life (QOL), whereas patients suffering from other cognition disorders with poor insight report better QOL. This study investigates the relationship between anosognosia, neglect and QOL amongst stroke survivors. Stroke survivors who met the criteria were used as a sampling pool. Sixty stroke patients were observed in this study, amongst whom 20 patients with anosognosia and neglect (A+N+), 20 patients with neglect but not anosognosia (A-N+) and 20 patients with neither anosognosia nor neglect (A-N-) were selected from the sampling pool based on demographic characteristics matched with the A+N+ group. A questionnaire (SS-QOL) was used to collect the QOL perceived by the stroke survivors. The perceived QOL of the A+N+ group was significantly better than those of the other groups, including the subscales of self-care, mobility, work/productivity, upper extremity, mood, family role and social role. However, the A+N+ group had poor balance level and more fall incidents were reported. The A+N+ group perceived better QOL but had more falls and poorer balance than the other groups. Health providers should work with caregivers aggressively in preventing accidents. © 2014 The Author(s) European Journal of Neurology © 2014 EFNS.

  12. Language in individuals with left hemisphere tumors: Is spontaneous speech analysis comparable to formal testing?

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    Rofes, Adrià; Talacchi, Andrea; Santini, Barbara; Pinna, Giampietro; Nickels, Lyndsey; Bastiaanse, Roelien; Miceli, Gabriele

    2018-01-31

    The relationship between spontaneous speech and formal language testing in people with brain tumors (gliomas) has been rarely studied. In clinical practice, formal testing is typically used, while spontaneous speech is less often evaluated quantitatively. However, spontaneous speech is quicker to sample and may be less prone to test/retest effects, making it a potential candidate for assessing language impairments when there is restricted time or when the patient is unable to undertake prolonged testing. To assess whether quantitative spontaneous speech analysis and formal testing detect comparable language impairments in people with gliomas. Specifically, we addressed (a) whether both measures detected comparable language impairments in our patient sample; and (b) which language levels, assessment times, and spontaneous speech variables were more often impaired in this subject group. Five people with left perisylvian gliomas performed a spontaneous speech task and a formal language assessment. Tests were administered before surgery, within a week after surgery, and seven months after surgery. Performance on spontaneous speech was compared with that of 15 healthy speakers. Language impairments were detected more often with both measures than with either measure independently. Lexical-semantic impairments were more common than phonological and grammatical impairments, and performance was equally impaired across assessment time points. Incomplete sentences and phonological paraphasias were the most common error types. In our sample both spontaneous speech analysis and formal testing detected comparable language impairments. Currently, we suggest that formal testing remains overall the better option, except for cases in which there are restrictions on testing time or the patient is too tired to undergo formal testing. In these cases, spontaneous speech may provide a viable alternative, particularly if automated analysis of spontaneous speech becomes more readily

  13. Use of prosodic cues in the production of idiomatic and literal sentences by individuals with right- and left-hemisphere damage.

    Science.gov (United States)

    Bélanger, Nathalie; Baum, Shari R; Titone, Debra

    2009-07-01

    The neural bases of prosody during the production of literal and idiomatic interpretations of literally plausible idioms was investigated. Left- and right-hemisphere-damaged participants and normal controls produced literal and idiomatic versions of idioms (He hit the books.) All groups modulated duration to distinguish the interpretations. LHD patients, however, showed typical speech timing difficulties. RHD patients did not differ from the normal controls. The results partially support a differential lateralization of prosodic cues in the two cerebral hemispheres [Van Lancker, D., & Sidtis, J. J. (1992). The identification of affective-prosodic stimuli by left- and right-hemisphere-damaged subjects: All errors are not created equal. Journal of Speech and Hearing Research, 35, 963-970]. Furthermore, extended final word lengthening appears to mark idiomaticity.

  14. Enhancement Of Motor Recovery Through Left Dorsolateral Prefrontal Cortex Stimulation After Acute Ischemic Stroke

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    Shahram Oveisgharan

    2017-02-01

    Full Text Available Background: Two previous studies, which investigated transcranial direct current stimulation (tDCS use in motor recovery after acute ischemic stroke, did not show tDCS to be effective in this regard. We speculated that additional left dorsolateral prefrontal cortex ‎(DLPFC ‎stimulation may enhance post stroke motor recovery.  ‎ Methods: In the present randomized clinical trial, 20 acute ischemic stroke patients were recruited. Patients received real motor cortex (M1 stimulation in both arms of the trial. The two arms differed in terms of real vs. sham stimulation over the left DLPFC‎. Motor component of the Fugl-Meyer upper extremity assessment (FM and Action Research Arm Test (ARAT scores were used to assess primary outcomes, and non-linear mixed effects models were used for data analyses. Results: Primary outcome measures improved more and faster among the real stimulation group. During the first days of stimulations, sham group’s FM scores increased 1.2 scores per day, while real group’s scores increased 1.7 scores per day (P = 0.003. In the following days, FM improvement decelerated in both groups. Based on the derived models, a hypothetical stroke patient with baseline FM score of 15 improves to 32 in the sham stimulation group and to 41 in the real stimulation group within the first month after stroke. Models with ARAT scores yielded nearly similar results. Conclusion: The current study results showed that left DLPFC‎ stimulation in conjunction with M1 stimulation resulted in better motor recovery than M1 stimulation alone.

  15. The Influence of Visual and Auditory Information on the Perception of Speech and Non-Speech Oral Movements in Patients with Left Hemisphere Lesions

    Science.gov (United States)

    Schmid, Gabriele; Thielmann, Anke; Ziegler, Wolfram

    2009-01-01

    Patients with lesions of the left hemisphere often suffer from oral-facial apraxia, apraxia of speech, and aphasia. In these patients, visual features often play a critical role in speech and language therapy, when pictured lip shapes or the therapist's visible mouth movements are used to facilitate speech production and articulation. This demands…

  16. Increased emergence of alpha activity over the left but not the right temporal lobe within a dark acoustic chamber: differential response of the left but not the right hemisphere to transcerebral magnetic fields.

    Science.gov (United States)

    Persinger, M A

    1999-11-01

    The percentages of alpha activity per minute over the left and right temporal lobes were measured for the first and second successive 15-min intervals while subjects wore opaque goggles within an acoustic chamber. A weak (5 microT), burst-firing magnetic field was presented during this period for 1 s every 4 s primarily over the left or the right cerebral hemisphere. The results indicated that the left temporal lobe became less vigilant between the first and second 15 min while the right temporal lobe did not. When standardized scores for each subject's measures over time and across hemispheres were employed, increased alpha time over the left temporal lobe relative to the right temporal lobe was observed only when the transcerebral magnetic field was applied over the left hemisphere. Stimulation of the right hemisphere did not evoke this discrepancy. The detection of the effects of this specific complex magnetic field upon electroencephalographic activity may be more probable when the subjects are exposed to partial sensory deprivation.

  17. Fatal stroke after completion pneumonectomy for torsion of left upper lobe following left lower lobectomy

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    Apostolakis Efstratios

    2006-09-01

    Full Text Available Abstract Background The lobar torsion after lung surgery is a rare complication with an incidence of 0.09 to 0.4 %. It may occur after twisting of the bronchovascular pedicle of the remaining lobe after lobectomy, usually on the right side. The 180-degree rotation of the pedicle produces an acute obstruction of the lobar bronchus (atelectasis and of the lobar vessels as well. Without prompt treatment it progresses to lobar ischemia, pulmonary infarction and finally fatal gangrene. Case Presentation A 62 years old female patient was admitted for surgical treatment of lung cancer. She underwent elective left lower lobectomy for squamous cell carcinoma (pT2 N0. The operation was unremarkable, and the patient was extubated in the operating room. After eight hours the patient established decrease of pO2 and chest x-ray showed atelectasis of the lower lobe. To establish diagnosis, bronchoscopy was performed, demonstrating obstructed left lobar bronchus. The patient was re-intubated, and admitted to the operating room where reopening of the thoracotomy was performed. Lobar torsion was diagnosed, with the diaphragmatic surface of the upper lobe facing in an anterosuperior orientation. A completion pneumonectomy was performed. At the end of the procedure the patient developed a right pupil dilatation, presumably due to a cerebral embolism. A subsequent brain angio-CT scan established the diagnosis. She died at the intensive care unit 26 days later. Conclusion The thoracic surgeon should suspect this rare early postoperative complication after any thoracic operation in every patient with atelectasis of the neighboring lobe. High index of suspicion and prompt diagnosis may prevent catastrophic consequences, such as, infarction or gangrene of the pulmonary lobe. During thoracic operations, especially whenever the lung or lobe hilum is full mobilized, fixation of the remaining lobe may prevent this life threatening complication.

  18. Continuous theta burst stimulation (cTBS on left cerebellar hemisphere affects mental rotation tasks during music listening.

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    Silvia Picazio

    Full Text Available Converging evidence suggests an association between spatial and music domains. A cerebellar role in music-related information processing as well as in spatial-temporal tasks has been documented. Here, we investigated the cerebellar role in the association between spatial and musical domains, by testing performances in embodied (EMR or abstract (AMR mental rotation tasks of subjects listening Mozart Sonata K.448, which is reported to improve spatial-temporal reasoning, in the presence or in the absence of continuous theta burst stimulation (cTBS of the left cerebellar hemisphere. In the absence of cerebellar cTBS, music listening did not influence either MR task, thus not revealing a "Mozart Effect". Cerebellar cTBS applied before musical listening made subjects faster (P = 0.005 and less accurate (P = 0.005 in performing the EMR but not the AMR task. Thus, cerebellar inhibition by TBS unmasked the effect of musical listening on motor imagery. These data support a coupling between music listening and sensory-motor integration in cerebellar networks for embodied representations.

  19. Motor Unit Activity during Fatiguing Isometric Muscle Contraction in Hemispheric Stroke Survivors

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    Lara McManus

    2017-11-01

    Full Text Available Enhanced muscle weakness is commonly experienced following stroke and may be accompanied by increased susceptibility to fatigue. To examine the contributions of central and peripheral factors to isometric muscle fatigue in stroke survivors, this study investigates changes in motor unit (MU mean firing rate, and action potential duration during, and directly following, a sustained submaximal fatiguing contraction at 30% maximum voluntary contraction (MVC. A series of short contractions of the first dorsal interosseous muscle were performed pre- and post-fatigue at 20% MVC, and again following a 10-min recovery period, by 12 chronic stroke survivors. Individual MU firing times were extracted using surface EMG decomposition and used to obtain the spike-triggered average MU action potential waveforms. During the sustained fatiguing contraction, the mean rate of change in firing rate across all detected MUs was greater on the affected side (-0.02 ± 0.03 Hz/s than on the less-affected side (-0.004 ± 0.003 Hz/s, p = 0.045. The change in firing rate immediately post-fatigue was also greater on the affected side than less-affected side (-13.5 ± 20 and 0.1 ± 19%, p = 0.04. Mean MU firing rates increased following the recovery period on the less-affected side when compared to the affected side (19.3 ± 17 and 0.5 ± 20%, respectively, p = 0.03. MU action potential duration increased post-fatigue on both sides (10.3 ± 1.2 to 11.2 ± 1.3 ms on the affected side and 9.9 ± 1.7 to 11.2 ± 1.9 ms on the less-affected side, p = 0.001 and p = 0.02, respectively, and changes in action potential duration tended to be smaller in subjects with greater impairment (p = 0.04. This study presents evidence of both central and peripheral fatigue at the MU level during isometric fatiguing contraction for the first time in stroke survivors. Together, these preliminary observations indicate that the response to an isometric fatiguing contraction differs between the

  20. Right: Left:: East: West. Evidence that individuals from East Asian and South Asian cultures emphasize right hemisphere functions in comparison to Euro-American cultures.

    Science.gov (United States)

    Rozin, Paul; Moscovitch, Morris; Imada, Sumio

    2016-09-01

    We present evidence that individuals from East or South Asian cultures (Japanese college students in Japan and East or South Asian born and raised college students in the USA) tend to exhibit default thinking that corresponds to right hemisphere holistic functions, as compared to Caucasian individuals from a Western culture (born and raised in the USA). In two lateralized tasks (locating the nose in a scrambled face, and global-local letter task), both Asian groups showed a greater right hemisphere bias than the Western group. In a third lateralized task, judging similarity in terms of visual form versus functional/semantic categorizations, there was not a reliable difference between the groups. On a classic, ambiguous face composed of vegetables, both Eastern groups displayed a greater right hemisphere (holistic face processing) bias than the Western group. These results support an "East - Right Hemisphere, West - Left Hemisphere" hypothesis, as originally proposed by Ornstein (1972). This hypothesis is open as to the degree to which social-cultural forces were involved in hemispheric specialization, or the opposite, or both. Our aim is to encourage a more thorough analysis of this hypothesis, suggesting both lateralization studies corresponding to documented East-West differences, and East-West studies corresponding to lateralization differences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Transcranial brain stimulation (TMS and tDCS for post-stroke aphasia rehabilitation: Controversies

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    Lucia Iracema Zanotto de Mendonça

    Full Text Available Transcranial brain stimulation (TS techniques have been investigated for use in the rehabilitation of post-stroke aphasia. According to previous reports, functional recovery by the left hemisphere improves recovery from aphasia, when compared with right hemisphere participation. TS has been applied to stimulate the activity of the left hemisphere or to inhibit homotopic areas in the right hemisphere. Various factors can interfere with the brain's response to TS, including the size and location of the lesion, the time elapsed since the causal event, and individual differences in the hemispheric language dominance pattern. The following questions are discussed in the present article: [a] Is inhibition of the right hemisphere truly beneficial?; [b] Is the transference of the language network to the left hemisphere truly desirable in all patients?; [c] Is the use of TS during the post-stroke subacute phase truly appropriate? Different patterns of neuroplasticity must occur in post-stroke aphasia.

  2. Language learning and brain reorganization in a 3.5-year-old child with left perinatal stroke revealed using structural and functional connectivity.

    Science.gov (United States)

    François, Clément; Ripollés, Pablo; Bosch, Laura; Garcia-Alix, Alfredo; Muchart, Jordi; Sierpowska, Joanna; Fons, Carme; Solé, Jorgina; Rebollo, Monica; Gaitán, Helena; Rodriguez-Fornells, Antoni

    2016-04-01

    Brain imaging methods have contributed to shed light on the possible mechanisms of recovery and cortical reorganization after early brain insult. The idea that a functional left hemisphere is crucial for achieving a normalized pattern of language development after left perinatal stroke is still under debate. We report the case of a 3.5-year-old boy born at term with a perinatal ischemic stroke of the left middle cerebral artery, affecting mainly the supramarginal gyrus, superior parietal and insular cortex extending to the precentral and postcentral gyri. Neurocognitive development was assessed at 25 and 42 months of age. Language outcomes were more extensively evaluated at the latter age with measures on receptive vocabulary, phonological whole-word production and linguistic complexity in spontaneous speech. Word learning abilities were assessed using a fast-mapping task to assess immediate and delayed recall of newly mapped words. Functional and structural imaging data as well as a measure of intrinsic connectivity were also acquired. While cognitive, motor and language levels from the Bayley Scales fell within the average range at 25 months, language scores were below at 42 months. Receptive vocabulary fell within normal limits but whole word production was delayed and the child had limited spontaneous speech. Critically, the child showed clear difficulties in both the immediate and delayed recall of the novel words, significantly differing from an age-matched control group. Neuroimaging data revealed spared classical cortical language areas but an affected left dorsal white-matter pathway together with right lateralized functional activations. In the framework of the model for Social Communication and Language Development, these data confirm the important role of the left arcuate fasciculus in understanding and producing morpho-syntactic elements in sentences beyond two word combinations and, most importantly, in learning novel word-referent associations, a

  3. Asymmetry and symmetry in brain waves from dolphin left and right hemispheres: some observations after anesthesia, during quiescent hanging behavior, and during visual obstruction.

    Science.gov (United States)

    Ridgway, S H

    2002-01-01

    Studies of sleep in cetaceans (whales, dolphins, and porpoises), substantiated by electrophysiological data, are rare with the great majority of observations having been made by one group from Russia. This group employed hard-wired recording with low-noise cables for their EEG observations, whereas our report describes behavioral and EEG observations of dolphin sleep using telemetry. Marked asymmetry of the EEG was observed during behavioral sleep posture. At different times synchronized slow waves appeared in both left and right brain hemispheres concurrently with lower voltage, faster, desynchronized EEG activity in the opposite hemisphere. On the other hand, during one brief period of sleep behavior, sleep-like EEG activity appeared on leads from both hemispheres. When the animal was exposed to a loud sound, it woke with lower voltage, faster, relatively symmetrical, desynchronized EEG activity appearing from both hemispheres. Additionally, the EEG appeared relatively desynchronized and symmetrical between the two hemispheres when the animal was awake during recovery from pentothal-halothane anesthesia as well as during waking periods when one or both of the animal's eyes were covered by an opaque rubber suction cup. Copyright 2002 S. Karger AG, Basel

  4. Novel Methods to Study Aphasia Recovery after Stroke

    DEFF Research Database (Denmark)

    Hartwigsen, Gesa; Siebner, Hartwig R

    2013-01-01

    The neural mechanisms that support aphasia recovery are not yet fully understood. It has been argued that the functional reorganization of language networks after left-hemisphere stroke may engage perilesional left brain areas as well as homologous right-hemisphere regions. In this chapter, we...... that language recovery after stroke may integrate left- as well as right-hemisphere brain regions to a different degree over the time course of recovery. Although the results of these preliminary studies provide some evidence that noninvasive brain stimulation may promote aphasia recovery, the reported effect...

  5. Effects of repetitive transcranial magnetic stimulation combined with sensory cueing on unilateral neglect in subacute patients with right hemispheric stroke: a randomized controlled study.

    Science.gov (United States)

    Yang, Nicole Yh; Fong, Kenneth Nk; Li-Tsang, Cecilia Wp; Zhou, D

    2017-09-01

    To compare the effects of rTMS combined with sensory cueing, rTMS alone, and conventional rehabilitation on unilateral neglect, hemiplegic arm functions and performance of activities of daily living. A single-blinded randomized controlled trial. A convalescent hospital. Sixty inpatients with left unilateral neglect after stroke. Patients were randomly assigned to three groups: rTMS combined with sensory cueing, rTMS, and conventional rehabilitation alone. rTMS at 1 Hz was applied over P5 of the contralesional hemisphere while vibration cueing was emitted using a wristwatch device on the hemiplegic arm, five days per week for two weeks. The first two groups received the same dosage of conventional rehabilitation on top of their experimental interventions. Blinded assessments were administered at baseline, 2 weeks postintervention, and 6 weeks follow-up. Neglect and arm motor performance. Both rTMS combined with sensory cueing (99.6±33.0) and rTMS alone (88.2±28.7) significantly reduced unilateral neglect than conventional rehabilitation (72.7±33.1) when measured using the conventional subtests of the Behavioural Inattention Test, but the combination was better than rTMS alone. Hemiplegic arm functions and activities of daily living improved in all patients across the three groups but no significant differences were found between the groups. The combination of inhibitory P5-rTMS with sensory cueing was better than either rTMS or conventional rehabilitation alone in producing a stronger and long-lasting improvement in unilateral neglect, but the improvement was not associated with improved arm function or independence in activities of daily living.

  6. False memories to emotional stimuli are not equally affected in right- and left-brain-damaged stroke patients.

    Science.gov (United States)

    Buratto, Luciano Grüdtner; Zimmermann, Nicolle; Ferré, Perrine; Joanette, Yves; Fonseca, Rochele Paz; Stein, Lilian Milnitsky

    2014-10-01

    Previous research has attributed to the right hemisphere (RH) a key role in eliciting false memories to visual emotional stimuli. These results have been explained in terms of two right-hemisphere properties: (i) that emotional stimuli are preferentially processed in the RH and (ii) that visual stimuli are represented more coarsely in the RH. According to this account, false emotional memories are preferentially produced in the RH because emotional stimuli are both more strongly and more diffusely activated during encoding, leaving a memory trace that can be erroneously reactivated by similar but unstudied emotional items at test. If this right-hemisphere hypothesis is correct, then RH damage should result in a reduction in false memories to emotional stimuli relative to left-hemisphere lesions. To investigate this possibility, groups of right-brain-damaged (RBD, N=15), left-brain-damaged (LBD, N=15) and healthy (HC, N=30) participants took part in a recognition memory experiment with emotional (negative and positive) and non-emotional pictures. False memories were operationalized as incorrect responses to unstudied pictures that were similar to studied ones. Both RBD and LBD participants showed similar reductions in false memories for negative pictures relative to controls. For positive pictures, however, false memories were reduced only in RBD patients. The results provide only partial support for the right-hemisphere hypothesis and suggest that inter-hemispheric cooperation models may be necessary to fully account for false emotional memories. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. A modified Glenn shunt reduces right ventricular stroke work during left ventricular assist device therapy.

    Science.gov (United States)

    Schiller, Petter; Vikholm, Per; Hellgren, Laila

    2016-03-01

    Right ventricular (RV) failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) placement and remains hard to predict. We hypothesized that partial surgical exclusion of the RV with a modified Glenn shunt during LVAD treatment would reduce RV stroke work. An LVAD was implanted in eight pigs and a modified Glenn shunt was constructed. A conductance pressure-volume catheter was placed in the right ventricle through the apex. Haemodynamic data and pressure-volume loops were obtained at the following time periods: (i) baseline, (ii) open shunt, (iii) LVAD with closed shunt and (iii) LVAD and open shunt. During LVAD therapy, the right atrial (RA) pressure increased from 9 mmHg (9-9) to 15 mmHg (12-15), P = 0.01. RV stroke volume increased from 30 ml (29-40) to 51 ml (42-53), P < 0.01. Also, RV stroke work increased to 708 mmHg ml (654-1193) from 535 mmHg ml (424-717), P = 0.04, compared with baseline. During LVAD therapy in combination with a Glenn shunt, the RA pressure decreased from 15 mmHg (12-15) to 10 mmHg (7-11) when compared with LVAD therapy only, P = 0.01. A decrease in RV stroke work from 708 mmHg ml (654-1193) to 465 mmHg ml (366-711), P = 0.04, was seen when the LVAD was combined with a shunt, not significantly different from the baseline value (535 mmHg ml). The developed pressure in the right ventricle decreased from 29 mmHg (26-32) to 21 mmHg (20-24), P < 0.01. The pressure-volume loops of the RV show a significant reduction of RV stroke work during the use of the shunt with LVAD treatment. A modified Glenn shunt reduced RV volumes, RV stroke work and RA pressure during LVAD therapy in an experimental model of heart failure in pigs. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  8. Damage to the Left Precentral Gyrus Is Associated With Apraxia of Speech in Acute Stroke.

    Science.gov (United States)

    Itabashi, Ryo; Nishio, Yoshiyuki; Kataoka, Yuka; Yazawa, Yukako; Furui, Eisuke; Matsuda, Minoru; Mori, Etsuro

    2016-01-01

    Apraxia of speech (AOS) is a motor speech disorder, which is clinically characterized by the combination of phonemic segmental changes and articulatory distortions. AOS has been believed to arise from impairment in motor speech planning/programming and differentiated from both aphasia and dysarthria. The brain regions associated with AOS are still a matter of debate. The aim of this study was to address this issue in a large number of consecutive acute ischemic stroke patients. We retrospectively studied 136 patients with isolated nonlacunar infarcts in the left middle cerebral artery territory (70.5±12.9 years old, 79 males). In accordance with speech and language assessments, the patients were classified into the following groups: pure form of AOS (pure AOS), AOS with aphasia (AOS-aphasia), and without AOS (non-AOS). Voxel-based lesion-symptom mapping analysis was performed on T2-weighted images or fluid-attenuated inversion recovery images. Using the Liebermeister method, group-wise comparisons were made between the all AOS (pure AOS plus AOS-aphasia) and non-AOS, pure AOS and non-AOS, AOS-aphasia and non-AOS, and pure AOS and AOS-aphasia groups. Of the 136 patients, 22 patients were diagnosed with AOS (7 patients with pure AOS and 15 patients with AOS-aphasia). The voxel-based lesion-symptom mapping analysis demonstrated that the brain regions associated with AOS were centered on the left precentral gyrus. Damage to the left precentral gyrus is associated with AOS in acute to subacute stroke patients, suggesting a role of this brain region in motor speech production. © 2015 American Heart Association, Inc.

  9. Selected Gray Matter Volumes and Gender but Not Basal Ganglia nor Cerebellum Gyri Discriminate Left Versus Right Cerebral Hemispheres: Multivariate Analyses in human Brains at 3T.

    Science.gov (United States)

    Roldan-Valadez, Ernesto; Suarez-May, Marcela A; Favila, Rafael; Aguilar-Castañeda, Erika; Rios, Camilo

    2015-07-01

    Interest in the lateralization of the human brain is evident through a multidisciplinary number of scientific studies. Understanding volumetric brain asymmetries allows the distinction between normal development stages and behavior, as well as brain diseases. We aimed to evaluate volumetric asymmetries in order to select the best gyri able to classify right- versus left cerebral hemispheres. A cross-sectional study performed in 47 right-handed young-adults healthy volunteers. SPM-based software performed brain segmentation, automatic labeling and volumetric analyses for 54 regions involving the cerebral lobes, basal ganglia and cerebellum from each cerebral hemisphere. Multivariate discriminant analysis (DA) allowed the assembling of a predictive model. DA revealed one discriminant function that significantly differentiated left vs. right cerebral hemispheres: Wilks' λ = 0.008, χ(2) (9) = 238.837, P vision and language; our findings favored the concept that lateralization has been evolutionary favored by mental processes increasing cognitive efficiency and brain capacity. © 2015 Wiley Periodicals, Inc.

  10. Hemispheric specialisation in selective attention and short-term memory: A fine-coarse model of left and right ear disadvantages

    Directory of Open Access Journals (Sweden)

    John E. Marsh

    2013-12-01

    Full Text Available Serial short-term memory is impaired by irrelevant sound, particularly when the sound changes acoustically. This acoustic effect is larger when the sound is presented to the left compared to the right ear (a left-ear disadvantage. Serial memory appears relatively insensitive to distraction from the semantic properties of a background sound. In contrast, short-term free recall of semantic-category exemplars is impaired by the semantic properties of background speech and relatively insensitive to the sound’s acoustic properties. This semantic effect is larger when the sound is presented to the right compared to the left ear (a right-ear disadvantage. In this paper, we outline a speculative neurocognitive fine-coarse model of these hemispheric differences in relation to short-term memory and selective attention, and explicate empirical directions in which this model can be critically evaluated.

  11. Left atrial function to identify patients with atrial fibrillation at high risk of stroke: new insights from a large registry.

    Science.gov (United States)

    Leung, Melissa; van Rosendael, Philippe J; Abou, Rachid; Ajmone Marsan, Nina; Leung, Dominic Y; Delgado, Victoria; Bax, Jeroen J

    2017-12-28

    Atrial fibrillation (AF) is an independent risk factor for ischaemic stroke. The CHA2DS2-VASc is the most widely used risk stratification model; however, echocardiographic refinement may be useful, particularly in low risk AF patients. The present study examined the association between advanced echocardiographic parameters and ischaemic stroke, independent of CHA2DS2-VASc score. One thousand, three hundred and sixty-one patients (mean age 65±12 years, 74% males) with first diagnosis of AF and baseline transthoracic echocardiogram were followed by chart review for the occurrence of stroke over a mean of 7.9 years. Left atrial (LA) volumes, LA reservoir strain, P-wave to A' duration on tissue Doppler imaging (PA-TDI, reflecting total atrial conduction time), and left ventricular (LV) global longitudinal strain (GLS) were evaluated in patients with and without stroke. The independent association of these echocardiographic parameters with the occurrence of ischaemic stroke was evaluated with Cox proportional hazard models. One-hundred patients (7%) developed an ischaemic stroke, representing an annualized stroke rate of 0.9%. The incident stroke rate in the year following the first diagnosis of AF was 2.6% in the entire population and higher than the remainder of the follow-up period. Left atrial reservoir (14.5% vs. 18.9%, P = 0.005) and conduit strains were reduced (10.5% vs. 13.5%, P = 0.013), and PA-TDI lengthened (166 ms vs. 141 ms, P Left atrial reservoir strain and PA-TDI were independently associated with risk of stroke in a model including CHA2DS2-VASc score, age, and anticoagulant use. The assessment of LA reservoir strain and PA-TDI on echocardiography after initial CHA2DS2-VASc scoring provides additional risk stratification for stroke and may be useful to guide decisions regarding anticoagulation for patients upon first diagnosis of AF.

  12. Three-dimensional analysis of the left atrial appendage for detecting paroxysmal atrial fibrillation in acute ischemic stroke.

    Science.gov (United States)

    Tanaka, Koji; Koga, Masatoshi; Sato, Kazuaki; Suzuki, Rieko; Minematsu, Kazuo; Toyoda, Kazunori

    2014-12-01

    Atrial fibrillation impairs left atrial appendage function and the thrombus formation in the left atrial appendage is a major cause of cardioembolic stroke. To evaluate the association between the volume of the left atrial appendage measured by real-time three-dimensional transesophageal echocardiography and presence of paroxysmal atrial fibrillation in patients with cerebral infarction or transient ischemic attack. Real-time three-dimensional transesophageal echocardiography was performed to measure left atrial appendage end-diastolic and end-systolic volumes to calculate left atrial appendage ejection fraction. Patients with normal sinus rhythm at the time of real-time three-dimensional transesophageal echocardiography were divided into groups with and without paroxysmal atrial fibrillation. Volumetric data were corrected with the body surface area. Of 146 patients registered, 102 (29 women, 72·2 ± 10·7 years) were normal sinus rhythm at the examination. In 23 patients with paroxysmal atrial fibrillation, left atrial appendage end-diastolic volume (4·78 ± 3·00 ml/m(2) vs. 3·14 ± 2·04 ml/m(2), P = 0·003) and end-systolic volume (3·10 ± 2·47 ml/m(2) vs. 1·39 ± 1·56 ml/m(2), P analysis, all these parameters were independently associated with paroxysmal atrial fibrillation after adjusting for sex, age, diabetes mellitus, and previous stroke. Left atrial appendage volumetric analysis by real-time three-dimensional transesophageal echocardiography is a promising method for detecting paroxysmal atrial fibrillation in acute cerebral infarction or transient ischemic attack. © 2014 The Authors. International Journal of Stroke © 2014 World Stroke Organization.

  13. Effects of primary caregiver participation in vestibular rehabilitation for unilateral neglect patients with right hemispheric stroke: a randomized controlled trial

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    Dai CY

    2013-04-01

    at days 14 and 28 in the areas of neglect, ADL, and balance. No significant difference was observed between the two groups in the number of falls. Conclusion: Neglect, ADL, and balance among UN patients with right hemispheric stroke can be improved through the participation of primary caregivers in VR. Trained informal caregivers were recommended to provide VR guidance and supervision to patients who suffer from UN. Keywords: neglect, vestibular rehabilitation, falls, balance, caregiver

  14. The left atrium, atrial fibrillation, and the risk of stroke in hypertensive patients with left ventricular hypertrophy

    DEFF Research Database (Denmark)

    Wachtell, K.; Devereux, R.B.; Lyle, P.A.

    2008-01-01

    The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study provided extensive data on predisposing factors, consequences, and prevention of atrial fibrillation (AF) in patients with hypertension and left ventricular (LV) hypertrophy. Randomized losartan-based treatment...

  15. Reward-system effect and “left hemispheric unbalance”: a comparison between drug addiction and high-BAS healthy subjects on gambling behavior

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    Roberta Finocchiaro

    2015-04-01

    Full Text Available Recent studies show the similarity of reward-related neurocircuitry and behavioral patterns between pathological gamblers and substance addictive patients. Evidences proved that pathological gambling (PG and Substance Use Disorders (SUD are associated with deficits in frontal lobe function and that they show similar behaviors to that of patients with bilateral VMPFC lesions. The present article aimed to compare the results of two studies concerning the relationship between the Behavioral Activation System (BAS and the hemispheric lateralisation effect that supports the gambling behavior in addiction disease. In the two studies we considered a group of Cocaine Addictive (CA patients and high-BAS healthy subjects who were tested using the Iowa Gambling Task. Also metacognitive questionary and alpha band modulation were considered. It was found that the “left hemisphere unbalance” may be considered as a critical marker of dysfunctional decision-making in addictive behaviors (drug addiction and gambling behaviours and a factor able to explain the tendency to opt in favor of more reward-related conditions.

  16. Headache and Central Positioning Vertigo in a Middle Aged Female-a Case of Solitary Cerebellar Tuberculoma Involving Left Cerebellar Hemisphere

    Directory of Open Access Journals (Sweden)

    Shakya Bhattacharjee

    2012-03-01

    Full Text Available A 48 year old female presented with headache and an illusory sensation of spinning of head in respect to environment for last 8 weeks. Her head spinning or vertigo had no particular direction or not precipitated by any specific head posture. Headache is non- specific in nature and intensified in last few days.Her neurological examination revealed a central positional vertigo with horizontal gaze evoked nystagmus and ataxia. Her MRI scan brain showed the presence of a large solitary ring enhancing lesion in the left cerebellar hemisphere. The lesion was surgically excised and was examined histopathologicaliy that revealed a chronic inflammatory granuloma with caseation necrosis and multinucleated giant cells suggestive of tuberculosis

  17. Performance of language tasks in patients with ruptured aneurysm of the left hemisphere worses in the post-surgical evaluation

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    Ana Cláudia C. Vieira

    2016-08-01

    Full Text Available ABSTRACT Sub-arachnoid hemorrhage (SAH promotes impairment of upper cortical functions. However, few information is available emphasizing changes in language after aneurismal SAH and aneurysm location influence. Objective To assess the language and verbal fluency performance in aneurismal SAH pre- and post-surgery in patients caused by an aneurysm of the anterior communicating artery (AcomA, left middle cerebral artery (L-MCA and left posterior comunicating artery (L-PcomA. Methods Assessment in 79 patients with SAH, on two occasions: pre- and post surgical treatment. They were divided into three groups by the aneurysms’ location. Results Deterioration is detected in the performance of all patients during the post-surgical period; L-MCA aneurysm patients displayed a reduction in verbal naming and fluency; L-PcomA patients deteriorated in the written language and fluency tasks. Conclusion After the surgical procedure the patients decreased in various language tasks and these differences in performance being directly related to the location of the aneurysm.

  18. Bilingualism yields language-specific plasticity in left hemisphere's circuitry for learning to read in young children.

    Science.gov (United States)

    Jasińska, K K; Berens, M S; Kovelman, I; Petitto, L A

    2017-04-01

    How does bilingual exposure impact children's neural circuitry for learning to read? Theories of bilingualism suggests that exposure to two languages may yield a functional and neuroanatomical adaptation to support the learning of two languages (Klein et al., 2014). To test the hypothesis that this neural adaptation may vary as a function of structural and orthographic characteristics of bilinguals' two languages, we compared Spanish-English and French-English bilingual children, and English monolingual children, using functional Near Infrared Spectroscopy neuroimaging (fNIRS, ages 6-10, N =26). Spanish offers consistent sound-to-print correspondences ("phonologically transparent" or "shallow"); such correspondences are more opaque in French and even more opaque in English (which has both transparent and "phonologically opaque" or "deep" correspondences). Consistent with our hypothesis, both French- and Spanish-English bilinguals showed hyperactivation in left posterior temporal regions associated with direct sound-to-print phonological analyses and hypoactivation in left frontal regions associated with assembled phonology analyses. Spanish, but not French, bilinguals showed a similar effect when reading Irregular words. The findings inform theories of bilingual and cross-linguistic literacy acquisition by suggesting that structural characteristics of bilinguals' two languages and their orthographies have a significant impact on children's neuro-cognitive architecture for learning to read. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Common hemisphericity of language and music in a musician. A case report.

    Science.gov (United States)

    Hofman, S; Klein, C; Arlazoroff, A

    1993-06-01

    Aphasia coupled with amusia is reported in a 73-year-old male musician who was a lawyer by profession. This condition followed an ischemic stroke in the lateral aspect of the parieto-occipital region of the left hemisphere. The patient's music production exhibits jargon amusia, similar to that in his verbal production. This case supports the thesis that language and music may share a common hemisphere.

  20. Mechanical dyssynchrony of the left atrium during sinus rhythm is associated with history of stroke in patients with atrial fibrillation.

    Science.gov (United States)

    Ciuffo, Luisa; Inoue, Yuko Y; Tao, Susumu; Gucuk Ipek, Esra; Balouch, Muhammad; Lima, Joao A C; Nazarian, Saman; Spragg, David D; Marine, Joseph E; Berger, Ronald D; Calkins, Hugh; Ashikaga, Hiroshi

    2018-04-01

    We sought to evaluate the relationship between left atrial (LA) mechanical dyssynchrony and history of stroke or transient ischaemic attack (TIA) in patients with atrial fibrillation (AF). We hypothesized that mechanical dyssynchrony of the LA is associated with history of stroke/TIA independent of LA function and Cardiac failure, Hypertension, Age, Diabetes, Stroke/transient ischaemic attack (TIA), VAscular disease, and Sex category (CHA2DS2-VASc) score in patients with AF. We conducted a cross-sectional study of 246 patients with a history of AF (59 ± 10 years, 29% female, 26% non-paroxysmal AF) referred for catheter ablation to treat drug-refractory AF who underwent preablation cardiac magnetic resonance (CMR) in sinus rhythm. Using tissue-tracking CMR, we measured the LA longitudinal strain and strain rate in each of 12 equal-length segments in two- and four-chamber views. We defined indices of LA mechanical dyssynchrony, including the standard deviation of the time to the peak longitudinal strain (SD-TPS). Patients with a prior history of stroke or TIA (n = 23) had significantly higher SD-TPS than those without (n = 223) (39.9 vs. 23.4 ms, P stroke/TIA after adjusting for the CHA2DS2-VASc score, LA minimum index volume, and the peak LA longitudinal strain (P stroke/TIA more accurately than CHA2DS2-VASc score alone (c-statistics: 0.82 vs. 0.75, P stroke/TIA in patients with AF.

  1. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output.

    Science.gov (United States)

    Smerup, Morten; Damkjær, Mads; Brøndum, Emil; Baandrup, Ulrik T; Kristiansen, Steen Buus; Nygaard, Hans; Funder, Jonas; Aalkjær, Christian; Sauer, Cathrine; Buchanan, Rasmus; Bertelsen, Mads Frost; Østergaard, Kristine; Grøndahl, Carsten; Candy, Geoffrey; Hasenkam, J Michael; Secher, Niels H; Bie, Peter; Wang, Tobias

    2016-02-01

    Giraffes--the tallest extant animals on Earth--are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. Arterial pressure may exceed 300 mmHg and has historically been attributed to an exceptionally large heart. Recently, this has been refuted by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It thus remains unexplained how the normal-sized giraffe heart generates such massive arterial pressures. We hypothesized that giraffe hearts have a small intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic pressures to calculate left ventricular wall stress. Cardiac output was also determined by inert gas rebreathing to provide an additional and independent estimate of stroke volume. Echocardiography and inert gas-rebreathing yielded similar cardiac outputs of 16.1±2.5 and 16.4±1.4 l min(-1), respectively. End-diastolic and end-systolic volumes were 521±61 ml and 228±42 ml, respectively, yielding an ejection fraction of 56±4% and a stroke volume of 0.59 ml kg(-1). Left ventricular circumferential wall stress was 7.83±1.76 kPa. We conclude that, relative to body mass, a small left ventricular cavity and a low stroke volume characterizes the giraffe heart. The adaptations result in typical mammalian left ventricular wall tensions, but produce a lowered cardiac output. © 2016. Published by The Company of Biologists Ltd.

  2. Left ventricular hypertrophy and risk of fatal and non-fatal stroke EUROSTROKE: a collaborative study among research centres in Europe

    NARCIS (Netherlands)

    M.L. Bots (Michiel); J. Tuomilehto; D.E. Grobbee (Diederick); P.J. Koudstaal (Peter Jan); Y. Nikitin; J.T. Salonen; P.C. Elwood; S. Malyutina; A. Freire de Concalves; J. Sivenius; A. di Carlo; P. Lagiou

    2002-01-01

    textabstractBACKGROUND: This study investigated the association between electrocardiographically assessed left ventricular hypertrophy (LVH) and fatal, non-fatal, haemorrhagic and ischaemic stroke in four European cohorts participating in EUROSTROKE. METHODS: EUROSTROKE is a

  3. A Left Atrial Myxoma Case with a History of Stroke on whom a Coronary Bypass Surgery was Performed

    Directory of Open Access Journals (Sweden)

    Cihangir Kaymaz

    2009-12-01

    Full Text Available Cardiac myxomas are the most frequently encountered benign cardiac tumors in adult groups. Patients with myxoma may suffer from variety of clinical features. A patient who had suffered from stroke a yearago came to our hospital with a chest pain complaint. In the echocardiography of the patient suffering from acute coronary syndrome, left ventricular disfunction and left atrial mass was determined. In the coronary angiography, LAD and Cx critical stenosis, and an abnormal feeding artery which roots from Cxperformed was observed. LIMA-AD, Ao-RCA bypass and mass exision withleft atriotomy was made. Cardiac tumor embolism which makes up a rare cause of cerebral embolies should be considered especiallyin patients with sinus rhythm. In the coronary angiography the feeding artery of the myxoma was shown. A patient who has underwent coronary bypass operation and left atrial myxoma exision has beenpresented as a case.

  4. Reversible hemispheric hypoperfusion in two cases of SMART syndrome.

    Science.gov (United States)

    Wai, Karmen; Balabanski, Anna; Chia, Nicholas; Kleinig, Timothy

    2017-09-01

    Stroke-like migraine attacks after radiation therapy (SMART) syndrome manifests as prolonged episodes of cortical dysfunction, years after cranial irradiation. We present two cases demonstrating reversible hemispheric hypoperfusion. Case 1 presented with left hemispheric symptoms following previous similar episodes. CT perfusion (CTP) demonstrated reversible hemispheric hypoperfusion; subsequent investigations were consistent with SMART syndrome. Case 2 presented following the third episode of a hemispheric syndrome with near-identical CTP abnormalities. L-arginine was administered with rapid reversal of clinical and CTP abnormalities. We conclude that SMART syndrome may demonstrate significant hypoperfusion on hyperacute CTP without subsequent infarction. Impaired cerebrovascular autoregulation probably contributes to cortical dysfunction in SMART syndrome. L-arginine warrants investigation as a potential treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Functional significance of ipsilesional motor deficits after unilateral stroke.

    Science.gov (United States)

    Chestnut, Caitilin; Haaland, Kathleen Y

    2008-01-01

    To determine whether ipsilesional motor skills, which have been related to independent functioning, are present chronically after unilateral stroke and are more common in people with apraxia than in those without apraxia. Observational cohort comparing the performance of an able-bodied control group, stroke patients with left- or right-hemisphere damage matched for lesion volume, and left-hemisphere stroke patients with and without ideomotor limb apraxia. Primary care Veterans Affairs and private medical center. Volunteer right-handed sample; stroke patients with left- or right-hemisphere damage about 4 years poststroke; a control group of demographically matched, able-bodied adults. Not applicable. Total time to perform the (1) Williams doors test and the (2) timed manual performance test (TMPT), which includes parts of the Jebsen-Taylor Hand Function Test. Ipsilesional motor deficits were present after left- or right-hemisphere stroke when using both measures, but deficits were consistently more common in patients with limb apraxia only for the TMPT. These findings add to a growing literature that suggests that ipsilesional motor deficits may have a functional impact in unilateral stroke patients, especially in patients with ideomotor limb apraxia.

  6. [Amusia and aphasia of Bolero's creator--influence of the right hemisphere on music].

    Science.gov (United States)

    Tudor, Lorraine; Sikirić, Predrag; Tudor, Katarina Ivana; Cambi-Sapunar, Liana; Radonić, Vedran; Tudor, Mario; Buca, Ante; Carija, Robert

    2008-07-01

    The experience with cortical localization (BA 44, 45, 22) of language (Broca, Wernicke and others) in the left hemisphere has been repeatedly tested over the last 150 years and is now generally accepted. A single case report with autopsy findings (Leborgne, Tan tan), has enabled to localize the seat of spoken language in the left third frontal convolution. As music and language have a lot in common and even share the same hearing system, it is logical to try to localize the cognitive centers for music too. The disabling neurological disease illness of Maurice Ravel (1875-1937), a French impressionist composer, is not the right example to localize music center as that of Broca's language center, but it demonstrates the role of the right hemisphere in music production. In the last five years of his life, Ravel suffered from an unknown disease that affected the left hemisphere causing aphasia, apraxia, alexia, agraphia and amusia. It was the reason why Ravel could not compose during the last years of his life. In contrast to Ravel, Shebalin and Britten continued writing music works of their own although aphasic after having sustained two strokes to the left hemisphere. While lacking clinical cases with selective ablative brain lesions, research into the music localization can be done using modern imaging technologies such as fMRI and PET. Exercising music (professionally) develops analytical process in the left hemisphere whereas other individuals process music in their right hemisphere. There is right ear (left hemisphere) predominance in musicians and vice versa in musical amateurs. Music lateralization towards the right hemisphere is seen in women and in inattentive listeners. It can be subject to cultural influence, so the Japanese process their traditional popular music in the left hemisphere, whereas Westerners process the same music in the right hemisphere. Music and language are processed separately; they are localized in homologous regions of the opposite

  7. PECULIARITIES OF THE CLINICAL COURSE OF THE EARLY RECOVERY PERIOD IN THE CEREBRAL ISCHEMIC HEMISPHERIC STROKE ON THE BACKGROUND OF THE COMPLEX REHABILITATION MEASURES

    Directory of Open Access Journals (Sweden)

    S. A. Medvedkova

    2014-12-01

    Full Text Available Aim. The important problem of the modern angioneurology is the diagnostics and treatment of cerebral stroke. Rehabilitation measures, especially during the early recovery period, are one of the strategic courses in the struggle against it. Methods and results. The clinical-paraclinical study of 81 patients has been made for the purpose of the determination of clinical peculiarities of the course of the early recovery period in the cerebral hemispheric ischemic stroke patients on the background of the complex rehabilitation measures. It was determined, that majority of the patients the debut of the disease appeared only in the nidal deficiency with the gradual start in the active time of the day. The functional outcome and indices of the quality of life, as well as the level of the dependence of the outside help were substantially up to the evidence of the neurological deficit during the acuity of the disease. Conclusion. The best dynamics of the reconstruction of clinical-neurological disorders, indices of the level of invalidization, as well as indices of the quality of life of patients in the early recovery period have been defined on the background of complex neurometabolic therapy.

  8. Intravenous thrombolysis in a patient with left atrial myxoma with acute ischemic stroke

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    Girish Baburao Kulkarni

    2014-01-01

    Full Text Available Intravenous thrombolysis (IVT is an accepted therapy in patients with acute ischemic stroke presenting within 3-4.5 hours of symptom onset. Selection of the patient for thrombolysis depends on the careful assessment for the risk of post thrombolysis symptomatic haemorrhage (6.2-8.9% which may be fatal. Atrial myxomas which are the commonest tumors of the heart are associated with stroke due to tumor/clot embolism. There are very few case reports of IVT and its outcome in patients with atrial myxoma with stroke. Some have reported successful thrombolysis, while others have reported intracerebral bleeding. In this report we describe our experience of IVT in atrial myxoma patient with ischemic stroke and review the relevant literature.

  9. Diagnosing Paroxysmal Atrial Fibrillation in Patients With Ischemic Strokes and Transient Ischemic Attacks Using Echocardiographic Measurements of Left Atrium Function

    DEFF Research Database (Denmark)

    Skaarup, Kristoffer Grundtvig; Christensen, Hanne Krarup; Høst, Nis

    2016-01-01

    Twenty-five to 35 percentage of stroke cases are cryptogenic, and it has been demonstrated that paroxysmal atrial fibrillation (AF) is the causal agent in up to 25% of these incidents. The purpose of this study was to investigate if left atrial (LA) parameters have value for diagnosing paroxysmal...... AF in patients with ischemic stroke (IS) and transient ischemic attack (TIA). We retrospectively analyzed 219 patients who after acute IS or TIA underwent a transthoracic echocardiographic examination. Patients were designated as patients with paroxysmal AF if they had one or more reported incidents...... of AF before or after their echocardiographic examination. Patients in the paroxysmal AF group were significantly older and had higher CHA2DS2-VASc score than patients without paroxysmal AF (p

  10. Music, Hemisphere Preference and Imagery.

    Science.gov (United States)

    Stratton, Valerie N.; Zalanowski, Annette H.

    Two experiments were conducted to determine a possible relationship between the right hemisphere, music perception, and mental imagery. The first experiment compared two groups of college students, one of which showed a preference for left hemisphere thinking (n=22) and the other a preference for right hemisphere thinking (n=20), in order to test…

  11. Voxel-based lesion symptom mapping analysis of depressive mood in patients with isolated cerebellar stroke: A pilot study

    Directory of Open Access Journals (Sweden)

    Na Young Kim, MD

    2017-01-01

    Voxel-wise subtraction and χ (Ayerbe et al., 2014 analyses indicated that damage to the left posterior cerebellar hemisphere was associated with depression. Significant correlations were also found between the severity of depressive symptoms and lesions in lobules VI, VIIb, VIII, Crus I, and Crus II of the left cerebellar hemisphere (Pcorrected = 0.045. Our results suggest that damage to the left posterior cerebellum is associated with increased depressive mood severity in patients with isolated cerebellar stroke.

  12. Cardiac right-to-left shunt subtypes in Chinese patients with cryptogenic strokes: a multicenter case-control study.

    Science.gov (United States)

    Xu, W H; Xing, Y Q; Yan, Z R; Jiang, J D; Gao, S

    2014-03-01

    Data on the possible association between cardiac right-to-left shunt (RLS) and cryptogenic stroke are lacking in Asians. RLS and its subtypes in Chinese cryptogenic stroke patients were investigated. Patients (n = 153, mean age 42 ± 10 years, 81 male) with cryptogenic stroke from four medical centers in China and 135 healthy volunteers (mean age 34 ± 8 years, 54 male) were recruited. Contrast transcranial Doppler was used to assess the prevalence of RLS. A three-level RLS categorization was applied as follows: none, 0 microbubbles (MBs); small, 1-25 MBs; and large, >25 MBs. RLS was considered latent if it occurred only after the Valsalva maneuver or permanent when it occurred also during normal respiration. Overall, RLS (P = 0.02), large RLS (P stroke than in healthy volunteers. The prevalences of small RLS and latent RLS in the two groups were similar (22% vs. 21% and 11% vs. 10%, respectively). The proportion of large RLSs amongst the subjects with RLS was much higher in the patient group than in healthy volunteers (45% vs. 18%, P vs. 64%, P = 0.11). Most large RLSs in the patient group (22/27, 81%) were permanent RLSs. Cardiac RLS is associated with cryptogenic stroke in Chinese. However, the higher prevalence of overall RLS in the patient group was mainly due to the increased proportion of large RLSs. The results only support large RLSs as a pathological condition. © 2014 The Author(s) European Journal of Neurology © 2014 EFNS.

  13. Prolonged corrected QT interval is predictive of future stroke events even in subjects without ECG-diagnosed left ventricular hypertrophy.

    Science.gov (United States)

    Ishikawa, Joji; Ishikawa, Shizukiyo; Kario, Kazuomi

    2015-03-01

    We attempted to evaluate whether subjects who exhibit prolonged corrected QT (QTc) interval (≥440 ms in men and ≥460 ms in women) on ECG, with and without ECG-diagnosed left ventricular hypertrophy (ECG-LVH; Cornell product, ≥244 mV×ms), are at increased risk of stroke. Among the 10 643 subjects, there were a total of 375 stroke events during the follow-up period (128.7±28.1 months; 114 142 person-years). The subjects with prolonged QTc interval (hazard ratio, 2.13; 95% confidence interval, 1.22-3.73) had an increased risk of stroke even after adjustment for ECG-LVH (hazard ratio, 1.71; 95% confidence interval, 1.22-2.40). When we stratified the subjects into those with neither a prolonged QTc interval nor ECG-LVH, those with a prolonged QTc interval but without ECG-LVH, and those with ECG-LVH, multivariate-adjusted Cox proportional hazards analysis demonstrated that the subjects with prolonged QTc intervals but not ECG-LVH (1.2% of all subjects; incidence, 10.7%; hazard ratio, 2.70, 95% confidence interval, 1.48-4.94) and those with ECG-LVH (incidence, 7.9%; hazard ratio, 1.83; 95% confidence interval, 1.31-2.57) had an increased risk of stroke events, compared with those with neither a prolonged QTc interval nor ECG-LVH. In conclusion, prolonged QTc interval was associated with stroke risk even among patients without ECG-LVH in the general population. © 2014 American Heart Association, Inc.

  14. Automatic segmentation of short association bundles using a new multi-subject atlas of the left hemisphere fronto-parietal brain connections.

    Science.gov (United States)

    Guevara, M; Seguel, D; Roman, C; Duclap, D; Lebois, A; Le Bihan; Mangin, J-F; Poupon, C; Guevara, P

    2015-08-01

    Human brain connection map is far from being complete. In particular the study of the superficial white matter (SWM) is an unachieved task. Its description is essential for the understanding of human brain function and the study of the pathogenesis associated to it. In this work we developed a method for the automatic creation of a SWM bundle multi-subject atlas. The atlas generation method is based on a cortical parcellation for the extraction of fibers connecting two different gyri. Then, an intra-subject fiber clustering is applied, in order to divide each bundle into sub-bundles with similar shape. After that, a two-step inter-subject fiber clustering is used in order to find the correspondence between the sub-bundles across the subjects, fuse similar clusters and discard the outliers. The method was applied to 40 subjects of a high quality HARDI database, focused on the left hemisphere fronto-parietal and insula brain regions. We obtained an atlas composed of 44 bundles connecting 22 pair of ROIs. Then the atlas was used to automatically segment 39 new subjects from the database.

  15. Coronary artery disease, left ventricular hypertrophy and diastolic dysfunction are associated with stroke in patients affected by persistent non-valvular atrial fibrillation: a case-control study.

    Science.gov (United States)

    Palmiero, Pasquale; Maiello, Maria; Passantino, Andrea

    2009-06-30

    Persistent non-valvular atrial fibrillation (NVAF) is associated with an increased risk of cardiovascular events such as stroke, and its rate is expected to rise because of the ageing population. The absolute rate of stroke depends on age and comorbidity. Risk stratification for stroke in patients with NVAF derives from populations enrolled in randomized clinical trials. However, participants in clinical trials are often not representative of the general population. Many stroke risk stratification scores have been used, but they do not include transthoracic echocardiogram (TTE), pulsate wave Doppler (PWD) and tissue Doppler imaging (TDI), simple and non- invasive diagnostic tools. The role of TTE, PWD and TDI findings has not been previously determined. Our study goal was to determine the association between TTE and PWD findings and stroke prevalence in a population of NVAF prone outpatients.PATIENTS WERE DIVIDED INTO TWO GROUPS: P for stroke prone and F for stroke free. There were no statistically significant differences between the two groups concerning cardiovascular risk factors, age (p=0.2), sex (p=0.2), smoking (p=0.3), diabetes (p=0.1) and hypercholesterolemia (p=0.2); hypertension was statistically significant (pdisease, previous acute myocardial infarction (AMI) (pdisease, with and without AMI, LVH and left ventricular diastolic dysfunction, but not left atrial dilatation. M-B mode echocardiography and PWD examination help to identify high-risk stroke patients among NVAF subjects; therefore, they may help in the selection of appropriate therapy for each patient.

  16. Transient Ischemic Attack and Ischemic Stroke in Danon Disease with Formation of Left Ventricular Apical Thrombus despite Normal Systolic Function

    Directory of Open Access Journals (Sweden)

    Takeshi Tsuda

    2017-01-01

    Full Text Available Danon disease is a rare X-linked dominant skeletal and cardiac muscle disorder presenting with hypertrophic cardiomyopathy, Wolf-Parkinson-White syndrome, skeletal myopathy, and mild intellectual disability. Early morbidity and mortality due to heart failure or sudden death are known in Danon disease, more in males than in females. Here, we present a 17-year-old female adolescent with Danon disease and severe concentric hypertrophy with normal left ventricular (LV systolic function, who has been complaining of intermittent headache and weakness for about 3 years, initially diagnosed with hemiplegic migraine. Subsequently, her neurological manifestation progressed to transient ischemic attack (TIA and eventually to ischemic stroke confirmed by CT scan with 1-day history of expressive aphasia followed by persistent left side weakness and numbness. Detailed echocardiogram for the first time revealed a small LV apical thrombus with unchanged severe biventricular hypertrophy and normal systolic function. This unexpected LV apical thrombus may be associated with a wide spectrum of neurological deficits ranging from TIA to ischemic stroke in Danon disease. Possibility of cerebral ischemic events should be suspected in Danon disease when presenting with neurological deficits even with normal systolic function. Careful assessment for LV apical thrombus is warranted in such cases.

  17. Left atrial appendage occlusion for stroke prevention in atrial fibrillation in Europe

    DEFF Research Database (Denmark)

    Lip, Gregory Y.H.; Dagres, Nikolaos; Proclemer, Alessandro

    2013-01-01

    was 10.6 per year and most (73%) centres performed ≤10 procedures per year. We found that LAAO was being performed for stroke prevention in AF, for the most common indication being 'the patient has absolute contraindication to long term oral anticoagulants'. Among survey respondents, LAAO procedures...... are most often performed by interventional cardiologists. Experience varied widely, and this was reflected in the wide range of thromboembolic and procedural (tamponade, bleeding) complications reported by the respondents to this EP wire survey....

  18. The Abundance of Epicardial Adipose Tissue Surrounding Left Atrium Is Associated With the Occurrence of Stroke in Patients With Atrial Fibrillation

    Science.gov (United States)

    Tsao, Hsuan-Ming; Hu, Wei-Chih; Tsai, Ping-Huang; Lee, Chao-Lin; Liu, Fang-Chun; Wang, Hsueh-Han; Lo, Li-Wei; Chang, Shih-Lin; Chao, Tze-Fan; Chen, Shih-Ann

    2016-01-01

    Abstract Epicardial adipose tissue (EAT) is positively associated with risk factors for cardiovascular disease, but the role of EAT in the development of atrial fibrillation (AF)-related stroke and its association with the anatomical and functional remodeling of the left atrium (LA) have not been elucidated. This was a comparative cross-sectional study. Twenty-seven patients with paroxysmal or persistent AF and cardioembolic stroke were selected and compared with 68 age- and sex-matched AF patients without stroke. In addition, 20 controls without a history of AF or stroke were included. The periatrial EAT and the structural and functional properties of the LA and left ventricle were evaluated using contrast-enhanced 64-slice multidetector computed tomography during sinus rhythm. Total EAT around the LA was significantly increased across the groups (control vs AF vs AF-related stroke, P EAT had a negative correlation with the dynamic function of the LA, LAA, and the HU ratio. After a multivariate analysis, increased EAT (P EAT was increased and was correlated with atrial dysfunction in patients with AF-related stroke. Hence, EAT assessment may potentially offer an incremental value for grading the risk of cardioembolic stroke in patients with AF. PMID:27057876

  19. A rare case of unruptured aneurysm of left coronary sinus of Valsalva accompanied with patent foramen ovale and atrial fibrillation detected after cardiac etiology stroke

    Directory of Open Access Journals (Sweden)

    Wolfgang Hohenforst-Schmidt

    2017-01-01

    Full Text Available We present a rare case of a 74 year old female with unruptured aneurysm of the left coronary sinus of Valsalva accompanied with patent foramen ovale and atrial fibrillation. This rare combination was detected during diagnostics for a cardiac etiology stroke. The left coronary sinus of Valsalva was reconstructed using an autologous pericardial patch, the left atrial appendage closed, left atrial ablation performed with cooled radiofrequency and the patent foramen ovale sutured directly. The patient was dismissed on the 12th postoperative day after having an uncomplicated postoperative course.

  20. Usefulness of left ventricular speckle tracking echocardiography and novel measures of left atrial structure and function in diagnosing paroxysmal atrial fibrillation in ischemic stroke and transient ischemic attack patients

    DEFF Research Database (Denmark)

    Skaarup, Kristoffer Grundtvig; Christensen, Hanne; Host, Nis

    2017-01-01

    Asymptomatic paroxysmal atrial fibrillation (PAF) is often assumed to be the cause of cryptogenic ischemic strokes (IS) and transient ischemic attacks (TIA). We examined the usefulness of measures obtained by 2D speckle tracking echocardiography and novel left atrial measurements, in the diagnosi...

  1. Left atrial appendage thrombus with resulting stroke post-RF ablation for atrial fibrillation in a patient on dabigatran.

    LENUS (Irish Health Repository)

    Lobo, R

    2015-11-01

    Dabigatran etexilate is licensed for use in prevention of deep venous thromboembolism and in prevention of stroke and systemic embolism in nonvalvular atrial fibrillation (AF). It has also been used in patients for other indications as a substitute for warfarin therapy because it requires no monitoring; one group being patients undergoing radiofrequency (RF), ablation for AF, although there have been no consensus guidelines with regards to dosage and timing of dose. We report the case of a patient with documentary evidence of left atrial appendage (LAA) thrombus formation and neurological sequelae post-RF ablation despite being on dabigatran. This case highlights the concern that periprocedural dabigatran may not provide adequate protection from development of LAA thrombus and that a standardised protocol will need to be developed and undergo large multicentre trials before dabigatran can be safely used for patients undergoing RF-ablation.

  2. Relationships of Balance, Gait Performance, and Functional Outcome in Chronic Stroke Patients: A Comparison of Left and Right Lesions.

    Science.gov (United States)

    Lopes, Priscila Garcia; Lopes, José Augusto Fernandes; Brito, Christina Moran; Alfieri, Fábio Marcon; Rizzo Battistella, Linamara

    2015-01-01

    This study compared the balance by center of pressure (COP) and its relationship with gait parameters and functional independence in left (LH) and right (RH) chronic stroke patients. In this cross-sectional study, twenty-one hemiparetic stroke patients were assessed for Functional Independence Measure (FIM), balance with a force platform, and gait in the Motion Analysis Laboratory. The amplitudes of the COP in the anteroposterior and mediolateral directions were similar in both groups. The anteroposterior direction was greater than the mediolateral direction. Only the temporal parameters showed any statistically significant differences. The LH showed a significant correlation between stride length, step length, and gait velocity with COP velocity sway for the healthy and paretic lower limbs. In both groups, the area of COP was significantly correlated with stride length. Motor FIM was significantly correlated with the COP in the LH group. There was no difference in the performance of balance, gait, and functional independence between groups. The correlation of the COP sway area with stride length in both groups can serve as a guideline in the rehabilitation of these patients where training the static balance may reflect the improvement of the stride length.

  3. Relationships of Balance, Gait Performance, and Functional Outcome in Chronic Stroke Patients: A Comparison of Left and Right Lesions

    Directory of Open Access Journals (Sweden)

    Priscila Garcia Lopes

    2015-01-01

    Full Text Available Introduction. This study compared the balance by center of pressure (COP and its relationship with gait parameters and functional independence in left (LH and right (RH chronic stroke patients. Methods. In this cross-sectional study, twenty-one hemiparetic stroke patients were assessed for Functional Independence Measure (FIM, balance with a force platform, and gait in the Motion Analysis Laboratory. Results. The amplitudes of the COP in the anteroposterior and mediolateral directions were similar in both groups. The anteroposterior direction was greater than the mediolateral direction. Only the temporal parameters showed any statistically significant differences. The LH showed a significant correlation between stride length, step length, and gait velocity with COP velocity sway for the healthy and paretic lower limbs. In both groups, the area of COP was significantly correlated with stride length. Motor FIM was significantly correlated with the COP in the LH group. Conclusion. There was no difference in the performance of balance, gait, and functional independence between groups. The correlation of the COP sway area with stride length in both groups can serve as a guideline in the rehabilitation of these patients where training the static balance may reflect the improvement of the stride length.

  4. Left atrial appendage occlusion for stroke prevention in atrial fibrillation: multicentre experience with the AMPLATZER Cardiac Plug.

    Science.gov (United States)

    Tzikas, Apostolos; Shakir, Samera; Gafoor, Sameer; Omran, Heyder; Berti, Sergio; Santoro, Gennaro; Kefer, Joelle; Landmesser, Ulf; Nielsen-Kudsk, Jens Erik; Cruz-Gonzalez, Ignacio; Sievert, Horst; Tichelbäcker, Tobias; Kanagaratnam, Prapa; Nietlispach, Fabian; Aminian, Adel; Kasch, Friederike; Freixa, Xavier; Danna, Paolo; Rezzaghi, Marco; Vermeersch, Paul; Stock, Friederike; Stolcova, Miroslava; Costa, Marco; Ibrahim, Reda; Schillinger, Wolfgang; Meier, Bernhard; Park, Jai-Wun

    2016-02-01

    To investigate the safety, feasibility, and efficacy of left atrial appendage occlusion (LAAO) with the AMPLATZER Cardiac Plug (ACP) for stroke prevention in patients with atrial fibrillation (AF). Data from consecutive patients treated in 22 centres were collected. A total of 1,047 patients were included in the study. Procedural success was 97.3%. There were 52 (4.97%) periprocedural major adverse events. Follow-up was complete in 1,001/1,019 (98.2%) of successfully implanted patients (average 13 months, total 1,349 patient-years). One-year all-cause mortality was 4.2%. No death at follow-up was reported as device-related. There were nine strokes (0.9%) and nine transient ischaemic attacks (0.9%) during follow-up. The annual rate of systemic thromboembolism was 2.3% (31/1,349 patient-years), which is a 59% risk reduction. There were 15 major bleedings (1.5%) during follow-up. The annual rate of major bleeding was 2.1% (28/1,349 patient-years), which is a 61% risk reduction. Patients with single LAAO on aspirin monotherapy or no therapy and longer follow-up had fewer cerebral and fewer bleeding events. In this multicentre study, LAAO with the ACP showed high procedural success and a favourable outcome for the prevention of AF-related thromboembolism. Modification in antithrombotic therapy after LAAO may result in reduction of bleeding events.

  5. Manual and oral apraxia in acute stroke, frequency and influence on functional outcome: The Copenhagen Stroke Study.

    Science.gov (United States)

    Pedersen, P M; Jørgensen, H S; Kammersgaard, L P; Nakayama, H; Raaschou, H O; Olsen, T S

    2001-09-01

    To determine the frequency of manual and oral apraxia in acute stroke and to examine the influence of these symptoms on functional outcome. Seven hundred seventy six unselected, acute stroke patients who were admitted within seven days of stroke onset with unimpaired consciousness were included. If possible, the patients were assessed for manual and oral apraxia on acute admission. Neurologic stroke severity including aphasia was assessed with the Scandinavian Stroke Scale, and activities of daily living function was assessed with the Barthel Index. All patients completed their rehabilitation in the same large stroke unit. Six hundred eighteen patients could cooperate with the apraxia assessments. Manual apraxia was found in 7% of subjects (10% in left and 4% in right hemispheric stroke; chi2 = 9.0; P = 0.003). Oral apraxia was found in 6% (9% in left and 4% in right hemispheric stroke; chi2 = 5.4; P = 0.02). Both manual and oral apraxia were related to increasing stroke severity, and manual, but not oral, apraxia was associated with increasing age. There was no gender difference in frequency of apraxia. Patients with either type of apraxia had temporal lobe involvement more often than patients without. When analyzed with multiple linear and logistic regression analyses, neither manual nor oral apraxia had any independent influence on functional outcome. Apraxia is significantly less frequent in unselected patients with acute stroke than has previously been assumed and has no independent negative influence on functional outcome.

  6. Stroke

    Science.gov (United States)

    ... adjust your treatment as needed. Rehabilitation After a stroke, you may need rehabilitation (rehab) to help you recover. Rehab may include working with speech, physical, and occupational therapists. Language, ... may have trouble communicating after a stroke. You may not be able to find the ...

  7. Left Ventricular Geometry Determines Prognosis and Reverse J-Shaped Relation Between Blood Pressure and Mortality in Ischemic Stroke Patients.

    Science.gov (United States)

    Park, Chan Soon; Park, Jun-Bean; Kim, Yerim; Yoon, Yeonyee E; Lee, Seung-Pyo; Kim, Hyung-Kwan; Kim, Yong-Jin; Cho, Goo-Yeong; Sohn, Dae-Won; Lee, Seung-Hoon

    2018-03-01

    This study sought to investigate the prognostic significance of left ventricular (LV) mass and geometry in ischemic stroke survivors, as well as the LV geometry-specific differences in the blood pressure-mortality relationship. LV mass and geometry are well-known prognostic factors in various populations; however, there are no data on their role in ischemic stroke patients. We prospectively recruited 2,328 consecutive patients admitted with acute ischemic stroke to our institute between 2002 and 2010. Of these, 2,069 patients were analyzed in whom echocardiographic data were available to assess LV mass and geometry. All-cause mortality was significantly greater in patients with concentric hypertrophy (adjusted hazard ratio [HR]: 1.417; 95% confidence interval [CI]: 1.045 to 1.920) and concentric remodeling (HR: 1.540; 95% CI: 1.115 to 2.127) but nonsignificantly in those with eccentric hypertrophy (HR: 1.388; 95% CI: 0.996 to 1.935) compared with normal geometry in multivariate analyses. Relative wall thickness was a significant predictor of all-cause mortality (HR: 1.149 per 0.1-U increase in relative wall thickness; 95% CI: 1.021 to 1.307), whereas LV mass index was not (HR: 1.003 per 1 g/m 2 increase in LV mass index; 95% CI: 0.999 to 1.007). Similar results were observed with cardiovascular mortality. In multivariable fractional polynomials, patients with altered LV geometry showed reverse J-curve relationships between acute-phase systolic blood pressure and all-cause or cardiovascular mortality, with the highest risks in the lower extremes, whereas those with normal geometry did not. Echocardiographic assessment of LV geometry provided independent and additive prognostic information in ischemic stroke patients. A reverse J-shaped relation of mortality with blood pressure was found in patients with abnormal LV geometry. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. Coronary artery disease, left ventricular hypertrophy and diastolic dysfunction are associated with stroke in patients affected by persistent non-valvular atrial fibrillation: a case-control study

    Directory of Open Access Journals (Sweden)

    Andrea Passantino

    2009-04-01

    Full Text Available Persistent non-valvular atrial fibrillation (NVAF is associated with an increased risk of cardiovascular events such as stroke, and its rate is expected to rise because of the ageing population. The absolute rate of stroke depends on age and comorbidity. Risk stratification for stroke in patients with NVAF derives from populations enrolled in randomized clinical trials. However, participants in clinical trials are often not representative of the general population. Many stroke risk stratification scores have been used, but they do not include transthoracic echocardiogram (TTE, pulsate wave Doppler (PWD and tissue Doppler imaging (TDI, simple and non-invasive diagnostic tools. The role of TTE, PWD and TDI findings has not been previously determined. Our study goal was to determine the association between TTE and PWD findings and stroke prevalence in a population of NVAF prone outpatients. Patients were divided into two groups: P for stroke prone and F for stroke free. There were no statistically significant differences between the two groups concerning cardiovascular risk factors, age (p=0.2, sex (p=0.2, smoking (p=0.3, diabetes (p=0.1 and hypercholesterolemia (p=0.2; hypertension was statistically significant (p less than 0.001. There were statistically significant differences concerning coronary artery disease, previous acute myocardial infarction (AMI (p less than 0.05 and non- AMI coronaropathy (p less than 0.04, a higher rate being in the P group. Concerning echo-Doppler findings, a higher statistically significant rate of left ventricular hypertrophy (LVH (p less than  0.05 and left ventricular diastolic dysfunction (p less than 0.001 was found in the P group and dilated left atrium (p LEFT ATRIAL APPENDAGE CLOSURE AS AN ALTERNATIVE TO WARFARIN FOR STROKE PREVENTION IN ATRIAL FIBRILLATION: A PATIENT¬LEVEL META¬ANALYSIS

    Directory of Open Access Journals (Sweden)

    2015-01-01

    Full Text Available Holmes D.R. Jr, Doshi S.K., Kar S., et al. Left Atrial Appendage Closure as an Alternative to Warfarin for Stroke Prevention in Atrial Fibrillation: A Patient­Level Meta­Analysis // J. Am. Coll. Cardiol. – 2015. – Vol. 65. – P. 2614–2623.

  9. Higher levels of serum fibrin-monomer reflect hypercoagulable state and thrombus formation in the left atrial appendage in patients with acute ischemic stroke.

    Science.gov (United States)

    Okuyama, Hidenobu; Hirono, Osamu; Liu, Ling; Takeishi, Yasuchika; Kayama, Takamasa; Kubota, Isao

    2006-08-01

    It is sometimes difficult to make a diagnosis of cardioembolic stroke in the stroke care unit, because of the splashing and vanishing of the intracardiac source of the emboli on transesophageal echocardiography. Serum fibrin-monomer (FM) is a new marker for coagulation activity that is useful for identifying older individuals at increased risk of ischemic stroke. Two hundred and four patients with acute ischemic stroke were examined for serum coagulation and fibrinolytic activity on admission, and underwent transesophageal echocardiography within 7 days of onset. Serum levels of FM was significantly higher in patients with left atrial appendage (LAA) thrombus formation (n=24) than in those with no thrombus (88+/-52 vs 14+/-9 microg/ml, pvs 8+/-5 microg/ml, pstroke.

  10. Does left atrial appendage closure with a cardiac plug system reduce the stroke risk in nonvalvular atrial fibrillation patients? A single-center case series.

    Science.gov (United States)

    Danna, Paolo; Proietti, Riccardo; Sagone, Antonio; Arensi, Andrea; Viecca, Maurizio; Rago, Anna; Russo, Vincenzo

    2013-03-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and it is associated with an increased stroke risk, due mainly to cardiac embolism from the left atrial appendage (LAA). Percutaneous LAA closure is a method to reduce stroke risk in AF without using anticoagulant agents. In this study we report data from an Italian experience with the LAA occluder Amplatzer Cardiac Plug (ACP) device (Aga Medical Corporation, Plymouth, MN, USA). The study was designed to evaluate the safety of LAA closure using ACP and the efficacy of the procedure in preventing strokes during a 1-year follow-up. Patients with permanent or paroxysmal AF, high stroke risk, and contraindication to warfarin therapy were selected for the procedure. The LAA closure was attempted in 37 patients and succeeded in 34 cases (91.9%). Four patients experienced serious complications (one cardiac tamponade requiring pericardiocentesis, two device embolizations, one low-rate response AF requiring artificial pacing). During a 1-year follow-up, ischemic stroke occurred in one of 34 patients, resulting in a stroke rate of 2.94%; thus there was a stroke rate reduction of 50.2% and 26.5% compared to the expected stroke rate, according to CHADS2 and CHA2 DS2 VASc score. None of the patients who received ACP experienced major bleeding during the follow-up. LAA closure using ACP is a relatively feasible procedure which can be performed by highly experienced operators to reduce stroke rate in patients with AF, high stroke risk, and contraindication to oral anticoagulants. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

  11. Differences between left- and right-sided neglect revisited: A large cohort study across multiple domains.

    Science.gov (United States)

    Ten Brink, Antonia F; Verwer, Jurre H; Biesbroek, J Matthijs; Visser-Meily, Johanna M A; Nijboer, Tanja C W

    2017-09-01

    Unilateral spatial neglect (USN) is a syndrome that can occur after right- and left-hemisphere damage. It is generally accepted that left-sided USN is more severe than right-sided USN. Evidence for such a difference in other domains is lacking. Primary aims were to compare frequency, severity, region specificity, cognition, physical functioning, and physical independence between left and right USN. Secondary aims were to compare lesion characteristics. A total of 335 stroke patients admitted for inpatient rehabilitation were included. The severity of the lateralized attentional deficit was measured with a shape cancellation and line bisection test (in peripersonal and extrapersonal space) and the Catherine Bergego scale. The Mini-Mental State Examination, Stichting Afasie Nederland score, search organization (i.e., best R and intersections rate), Motricity Index, balance, mobility, and self-care were assessed. Measures were statistically compared between left, right, and no USN patients. Lesion overlay plots were compared with lesion subtraction analyses. Left USN (15.82%) was more frequent than right USN (9.25%). Demographic and stroke characteristics were comparable between groups. The lateralized attentional deficit was most severe in left USN. USN in both peripersonal and extrapersonal space was more frequently left-sided in nature. Search efficiency was lower in left USN. Balance was poorer in right USN. No differences between left and right USN were found for cognitive ability, communication, motor strength, mobility, and self-care. Most patients with left USN had right-hemispheric lesions, whereas patients with right USN could have lesions in either the left or the right hemisphere. To conclude, left and right USN are both common after stroke. Although the lateralized attention deficit is worse in left than in right USN, consequences at the level of physical functioning and physical independence are largely comparable. From a clinical perspective, it is

  12. Incidence and types of sleep disorders in patients with stroke.

    Science.gov (United States)

    Pasic, Zejneba; Smajlovic, Dzevdet; Dostovic, Zikrija; Kojic, Biljana; Selmanovic, Senada

    2011-01-01

    Sleep disorders (SD) after stroke (stroke) are common occurrences, and most often in sleep apnea, insomnia and daytime sleepiness. GOALS. Research goals were to determine the types of SD and their frequency in patients with stroke in relation to the type of stroke and side of lesion. The study analyzed 200 patients with acute stroke hospitalized in the Clinic of Neurology, University Clinical Centre Tuzla in the period from 1st August 2007 to 1st June 2008. All patients have confirmed the existence of stroke by computerized tomography. SD was verified according to the General Curriculum of sleep, the Berlin questionnaire and Epvort scale. Stroke, by type, were divided into hemorrhagic and ischemic, and the localization of the stroke to right and left cerebral hemispheres. Of the total number of respondents, 78% had SD. Very serious level of SD had 42% of respondents, 20% moderate, and 16% of medium-severe degree. There was no statistically significant differences in the frequency of SD among patients with ischemic and hemorrhagic stroke (76.8%: 82.5%, p = 0.58). In relation to the side of lesion there was more patient with SD and stroke in the right cerebral hemisphere, but there were no statistically significant differences (39.5%: 33%, p = 0.1). According Epvort scale sleep apnea and snoring was present in 86%, daytime sleepiness in 49.5% and narcolepsy 0.5%. Sleep disturbance as a neuropsychological disorder has a significant incidence in the acute phase of stroke. SD is slightly more common in hemorrhagic stroke and stroke in the right hemisphere. Sleep Apnea and snoring are the most common types of SD in patients with stroke.

  13. Impact of chronic kidney disease on left atrial appendage occlusion for stroke prevention in patients with atrial fibrillation.

    Science.gov (United States)

    Kefer, Joelle; Tzikas, Apostolos; Freixa, Xavier; Shakir, Samera; Gafoor, Sameer; Nielsen-Kudsk, Jens Erik; Berti, Sergio; Santoro, Gennaro; Aminian, Adel; Landmesser, Ulf; Nietlispach, Fabian; Ibrahim, Reda; Danna, Paolo Luciano; Benit, Edouard; Budts, Werner; Stammen, Francis; De Potter, Tom; Tichelbäcker, Tobias; Gloekler, Steffen; Kanagaratnam, Prapa; Costa, Marco; Cruz-Gonzalez, Ignacio; Sievert, Horst; Schillinger, Wolfgang; Park, Jai-Wun; Meier, Bernhard; Omran, Heyder

    2016-03-15

    Left atrial appendage occlusion (LAAO) using the Amplatzer cardiac plug (ACP) is a preventive treatment of atrial fibrillation related thromboembolism. To assess the safety and efficacy of LAAO in patients with chronic kidney disease (CKD). Among the ACP multicentre registry, 1014 patients (75±8yrs) with available renal function were included. Patients with CKD (N=375, CHA2DS2-VASc: 4.9±1.5, HASBLED: 3.4±1.3) were at higher risk than patients without CKD (N=639, CHA2DS2-VASc: 4.2±1.6, HASBLED: 2.9±1.2; p<0.001 for both). Procedural (97%) and occlusion (99%) success were similarly high in all stages of CKD. Peri-procedural major adverse events (MAE) were observed in 5.1% of patients, 0.8% of death, with no difference between patients with and those without CKD (6.1 vs 4.5%, p=0.47). In patients with complete follow-up (1319 patients years), the annual stroke+transient ischaemic attack (TIA) rate was 2.3% and the observed bleeding rate was 2.1% (62 and 60% less than expected, similarly among patients with and those without CKD). Kaplan-Meier analysis showed a lower overall survival (84 vs 96% and 84 vs 93% at 1 and 2yrs. respectively; p<0.001) among patients with an eGFR <30ml/min/1.73m(2). LAAO using the ACP has a similar procedural safety among CKD patients compared to patients with normal renal function. LAAO with ACP offers a dramatic reduction of stroke+TIA rate and of bleeding rate persistent in all stages of CKD, as compared to the expected annual risk. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. Acupuncture at Waiguan (TE5) influences activation/deactivation of functional brain areas in ischemic stroke patients and healthy people: A functional MRI study.

    Science.gov (United States)

    Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Zeng, Tongjun; Wu, Junxian; Qu, Shanshan

    2013-01-25

    In the present study, 10 patients with ischemic stroke in the left hemisphere and six healthy controls were subjected to acupuncture at right Waiguan (TE5). In ischemic stroke subjects, functional MRI showed enhanced activation in Broadmann areas 5, 6, 7, 18, 19, 24, 32, the hypothalamic inferior lobe, the mamillary body, and the ventral posterolateral nucleus of the left hemisphere, and Broadmann areas 4, 6, 7, 18, 19 and 32 of the right hemisphere, but attenuated activation of Broadmann area 13, the hypothalamic inferior lobe, the posterior lobe of the tonsil of cerebellum, and the culmen of the anterior lobe of hypophysis, in the left hemisphere and Broadmann area 13 in the right hemisphere. In ischemic stroke subjects, a number of deactivated brain areas were enhanced, including Broadmann areas 6, 11, 20, 22, 37, and 47, the culmen of the anterior lobe of hypophysis, alae lingulae cerebella, and the posterior lobe of the tonsil of cerebellum of the left hemisphere, and Broadmann areas 8, 37, 45 and 47, the culmen of the anterior lobe of hypophysis, pars tuberalis adenohypophyseos, inferior border of lentiform nucleus, lateral globus pallidus, inferior temporal gyrus, and the parahippocampal gyrus of the right hemisphere. These subjects also exhibited attenuation of a number of deactivated brain areas, including Broadmann area 7. These data suggest that acupuncture at Waiguan specifically alters brain function in regions associated with sensation, vision, and motion in ischemic stroke patients. By contrast, in normal individuals, acupuncture at Waiguan generally activates brain areas associated with insomnia and other functions.

  15. Post-stroke hemiparesis: Does chronicity, etiology, and lesion side are associated with gait pattern?

    Science.gov (United States)

    Gama, Gabriela Lopes; Larissa, Coutinho de Lucena; Brasileiro, Ana Carolina de Azevedo Lima; Silva, Emília Márcia Gomes de Souza; Galvão, Élida Rayanne Viana Pinheiro; Maciel, Álvaro Cavalcanti; Lindquist, Ana Raquel Rodrigues

    2017-07-01

    Studies that evaluate gait rehabilitation programs for individuals with stroke often consider time since stroke of more than six months. In addition, most of these studies do not use lesion etiology or affected cerebral hemisphere as study factors. However, it is unknown whether these factors are associated with post-stroke motor performance after the spontaneous recovery period. To investigate whether time since stroke onset, etiology, and lesion side is associated with spatiotemporal and angular gait parameters of individuals with chronic stroke. Fifty individuals with chronic hemiparesis (20 women) were evaluated. The sample was stratified according to time since stroke (between 6 and 12 months, between 13 and 36 months, and over 36 months), affected cerebral hemisphere (left or right) and lesion etiology (ischemic and hemorrhagic). The participants were evaluated during overground walking at self-selected gait speed, and spatiotemporal and angular gait parameters were calculated. Results Differences between gait speed, stride length, hip flexion, and knee flexion were observed in subgroups stratified based on lesion etiology. Survivors of a hemorrhagic stroke exhibited more severe gait impairment. Subgroups stratified based on time since stroke only showed intergroup differences for stride length, and subgroups stratified based on affected cerebral hemisphere displayed between-group differences for swing time symmetry ratio. In order to recruit a more homogeneous sample, more accurate results were obtained and an appropriate rehabilitation program was offered, researchers and clinicians should consider that gait pattern might be associated with time since stroke, affected cerebral hemisphere and lesion etiology.

  16. Visual Attention in Posterior Stroke and Relations to Alexia

    DEFF Research Database (Denmark)

    Petersen, Anders; Vangkilde, Signe; Fabricius, Charlotte

    2016-01-01

    that reduced visual speed and span may explain pure alexia. Eight patients with unilateral PCA strokes (four left hemisphere, four right hemisphere) were selected on the basis of lesion location, rather than the presence of any visual symptoms. Visual attention was characterized by a whole report paradigm......Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere, while attentional effects of more posterior lesions are less clear. Commonly, such deficits are investigated in relation to specific syndromes like visual...... agnosia or pure alexia. The aim of this study was to characterize visual processing speed and apprehension span following posterior cerebral artery (PCA) stroke. In addition, the relationship between these attentional parameters and single word reading is investigated, as previous studies have suggested...

  17. EXAMINATION OF EXECUTIVE DYSFUNCTIONS IN STROKE SURVIVORS VIA 64 – WISCONSIN CARD SORTING TEST

    Directory of Open Access Journals (Sweden)

    Mirena Valkova

    2011-12-01

    Full Text Available Objective: The objective of our study was to examine executive dysfunctions in stroke survivors (three months after stroke via Wisconsin Card Scoring Test (WCST and to assess the influence of stroke severity and lesion location.Contingent and methods: We examined 20 stroke survivors with the following neuropsychological battery: MMSE, 21 – Hamilton test and WCST.Results: We found executive dysfunctions in 90% of our patients. Stroke severity measured by NIHSS influenced MMSE scoring and some of the WCST results (percent conceptual level, trials to complete first category, failure to maintain set and learning abilities. Patients with left hemispheric lesions had statistically significant higher level of total errors than patients with right hemispheric and brainstem lesions.Conclusion: Sub-acute stroke stage is strongly associated with executive dysfunctions

  18. Relationship of melatonin and serotonin levels with clinical neurological data in patients with cerebral ischemic hemispheric stroke during the early recovery stage of disease

    Directory of Open Access Journals (Sweden)

    S. O. Medvedkova

    2017-06-01

    Full Text Available The aim of the research is the improvement of diagnostic measures in patients with cerebral ischemic hemispheric stroke (CIHS on the basis of melatonin and serotonin plasma levels study in relation with evidence of neurologic impairment, level of functional independence, level of disability and their dynamics during the early recovery period of the disease. Materials and Methods. The complex clinical and paraclinical study of 77 patients (the average age 57,9±0,9 years was done in the early recovery period of the CIHS. The study of all patients was complex clinic and paraclinical: test according to National Institute of Health Stroke Scale (NIHSS, Barthel Index (BI, modified Rankin Scale (mRS was done on the 10th, 30th, 90th and 180th day of the disease; computer tomography of cerebrum was made on the first day of the disease; melatonin serum concentration and serotonin plasma level were determined on the 10th and 30th day from the onset of the CIHS. The melatonin/serotonin ratio (MSR = melatonin serum concentration / serotonin plasma level was also calculated. Results and Discussion. Statistical reliable relations between the following indications have been identified: «serotonin plasma level on the10th day - dynamics mRS score on the 30-90th day» (R=+0,37, p˂0,05, «melatonin serum concentration on the10th day - dynamics mRS score on the 30-90th day» (R=-0,23, p˂0,05,«MSR on the 10th day - dynamics mRS score on the 30-90th day» (R=-0,40, p˂0,05,«serotonin plasma level on the 30th day - BI score on the 90th day»(R=+0,38, p˂0,05,«serotonin plasma level on the 30th - BI score on the180th day»(R=+0,40, p˂0,05, «MSR on the 30th day - NIHSS score on the 180th day» (R=+0,29, p˂0,05, «MSR on the 30th day - mRS score on the 90th day» (R=+0,29, p˂0,05, «MSR on the 30th day - mRS score on the 180th day» (R=+0,32, p˂0,05, «MSR on the 30th day - BI score on the 90th day» (R=-0,42, p˂0,05, «MSR on the 30th day - BI score on the

  19. Ipsilateral hippocampal atrophy is associated with long-term memory dysfunction after ischemic stroke in young adults.

    Science.gov (United States)

    Schaapsmeerders, Pauline; van Uden, Inge W M; Tuladhar, Anil M; Maaijwee, Noortje A M; van Dijk, Ewoud J; Rutten-Jacobs, Loes C A; Arntz, Renate M; Schoonderwaldt, Hennie C; Dorresteijn, Lucille D A; de Leeuw, Frank-Erik; Kessels, Roy P C

    2015-07-01

    Memory impairment after stroke in young adults is poorly understood. In elderly stroke survivors memory impairments and the concomitant loss of hippocampal volume are usually explained by coexisting neurodegenerative disease (e.g., amyloid pathology) in interaction with stroke. However, neurodegenerative disease, such as amyloid pathology, is generally absent at young age. Accumulating evidence suggests that infarction itself may cause secondary neurodegeneration in remote areas. Therefore, we investigated the relation between long-term memory performance and hippocampal volume in young patients with first-ever ischemic stroke. We studied all consecutive first-ever ischemic stroke patients, aged 18-50 years, admitted to our academic hospital center between 1980 and 2010. Episodic memory of 173 patients was assessed using the Rey Auditory Verbal Learning Test and the Rey Complex Figure and compared with 87 stroke-free controls. Hippocampal volume was determined using FSL-FIRST, with manual correction. On average 10 years after stroke, patients had smaller ipsilateral hippocampal volumes compared with controls after left-hemispheric stroke (5.4%) and right-hemispheric stroke (7.7%), with most apparent memory dysfunctioning after left-hemispheric stroke. A larger hemispheric stroke was associated with a smaller ipsilateral hippocampal volume (b=-0.003, Pstroke (b=-0.028 ml, P=0.002) and right-hemispheric stroke (b=-0.015 ml, P=0.03). Our results suggest that infarction is associated with remote injury to the hippocampus, which may lower or expedite the threshold for cognitive impairment or even dementia later in life. © 2015 Wiley Periodicals, Inc.

  1. Effect of Right Insular Involvement on Death and Functional Outcome After Acute Ischemic Stroke in the IST-3 Trial (Third International Stroke Trial).

    Science.gov (United States)

    Sposato, Luciano A; Cohen, Geoffrey; Wardlaw, Joanna M; Sandercock, Peter; Lindley, Richard I; Hachinski, Vladimir

    2016-12-01

    In patients with acute ischemic stroke, whether involvement of the insular cortex influences outcome is controversial. Much of the apparent adverse outcome may relate to such strokes usually being severe. We examined the influence of right and left insular involvement on stroke outcomes among patients from the IST-3 study (Third International Stroke Trial) who had visible ischemic stroke on neuroimaging. We used multiple logistic regression to compare outcomes of left versus right insular and noninsular strokes across strata of stroke severity, on death, proportion dead or dependent, and level of disability (ordinalized Oxford Handicap Score) at 6 months, with adjustment for the effects of age, lesion size, and presence of atrial fibrillation. Of 3035 patients recruited, 2099 had visible ischemic strokes limited to a single hemisphere on computed tomography/magnetic resonance scans. Of these, 566 and 714 had infarction of right and left insula. Six months after randomization, right insular involvement was associated with increased odds of death when compared with noninsular strokes on the left side (adjusted odds ratio, 1.83; 95% confidence interval, 1.33-2.52), whereas the adjusted odds ratio comparing mortality after insular versus noninsular strokes on the left side was not significant. Among mild/moderate strokes, outcomes for right insular involvement were worse than for left insular, but among more severe strokes, the difference in outcomes was less substantial. We found an association between right insular involvement and higher odds of death and worse functional outcome. The difference between right- and left-sided insular lesions on outcomes seemed to be most evident for mild/moderate strokes. URL: http://www.isrctn.com. Unique identifier: ISRCTN25765518. © 2016 American Heart Association, Inc.

  2. Speech and the Right Hemisphere

    Directory of Open Access Journals (Sweden)

    E. M. R. Critchley

    1991-01-01

    Full Text Available Two facts are well recognized: the location of the speech centre with respect to handedness and early brain damage, and the involvement of the right hemisphere in certain cognitive functions including verbal humour, metaphor interpretation, spatial reasoning and abstract concepts. The importance of the right hemisphere in speech is suggested by pathological studies, blood flow parameters and analysis of learning strategies. An insult to the right hemisphere following left hemisphere damage can affect residual language abilities and may activate non-propositional inner speech. The prosody of speech comprehension even more so than of speech production—identifying the voice, its affective components, gestural interpretation and monitoring one's own speech—may be an essentially right hemisphere task. Errors of a visuospatial type may occur in the learning process. Ease of learning by actors and when learning foreign languages is achieved by marrying speech with gesture and intonation, thereby adopting a right hemisphere strategy.

  3. Speech and the right hemisphere.

    Science.gov (United States)

    Critchley, E M

    1991-01-01

    Two facts are well recognized: the location of the speech centre with respect to handedness and early brain damage, and the involvement of the right hemisphere in certain cognitive functions including verbal humour, metaphor interpretation, spatial reasoning and abstract concepts. The importance of the right hemisphere in speech is suggested by pathological studies, blood flow parameters and analysis of learning strategies. An insult to the right hemisphere following left hemisphere damage can affect residual language abilities and may activate non-propositional inner speech. The prosody of speech comprehension even more so than of speech production-identifying the voice, its affective components, gestural interpretation and monitoring one's own speech-may be an essentially right hemisphere task. Errors of a visuospatial type may occur in the learning process. Ease of learning by actors and when learning foreign languages is achieved by marrying speech with gesture and intonation, thereby adopting a right hemisphere strategy.

  4. Right Hemisphere Dominance in Visual Statistical Learning

    Science.gov (United States)

    Roser, Matthew E.; Fiser, Jozsef; Aslin, Richard N.; Gazzaniga, Michael S.

    2011-01-01

    Several studies report a right hemisphere advantage for visuospatial integration and a left hemisphere advantage for inferring conceptual knowledge from patterns of covariation. The present study examined hemispheric asymmetry in the implicit learning of new visual feature combinations. A split-brain patient and normal control participants viewed…

  5. Risk factors associated with falls in adult patients after stroke living in the community: baseline data from a stroke cohort in Brazil.

    Science.gov (United States)

    Pinto, Elen Beatriz; Nascimento, Carla; Marinho, Camila; Oliveira, Ilana; Monteiro, Maiana; Castro, Mayra; Myllane-Fernandes, Paula; Ventura, Laís M G B; Maso, Iara; Lopes, Antonio Alberto; Oliveira-Filho, Jamary

    2014-01-01

    Individuals with stroke have a high risk of falling, and their fall predictors may differ from those of other populations. To estimate fall frequency and identify factors related to fall occurrence in a sample of patients with stroke residing in the community. Clinical data were collected from 150 consecutive stroke patients with independent gait, and the following scales were applied: modified Barthel Index (mBI), Timed Up & Go Test (TUG), and National Institutes of Health Stroke Scale (NIHSS). Univariate analysis was performed; variables with possible association (P stroke onset (OR, 1.012 for every month increase; 95% CI, 1.002-1.021; P = .015) remained predictors. When we grouped individuals according to affected cerebral hemisphere, both hemispheres had similar accuracy, but TUG cutoff point was lower in individuals with right- versus left-hemisphere lesions. Patients with poor TUG performance, longer times since stroke onset, and right-hemisphere injury have particularly high fall rates, and TUG cutoff points for fall prediction vary according to cerebral hemisphere.

  6. Effect of fluid loading with normal saline and 6% hydroxyethyl starch on stroke volume variability and left ventricular volume

    Directory of Open Access Journals (Sweden)

    Kanda H

    2015-09-01

    Full Text Available Hirotsugu Kanda,1 Yuji Hirasaki,2 Takafumi Iida,1 Megumi Kanao,1 Yuki Toyama,1 Takayuki Kunisawa,1 Hiroshi Iwasaki,11Department of Anesthesiology and Critical Care Medicine, Asahikawa Medical University, Asahikawa, 2Department of Anatomy, The Jikei University Graduate School of Medicine, Tokyo, JapanPurpose: The aim of this clinical trial was to investigate changes in stroke volume variability (SVV and left ventricular end-diastolic volume (LVEDV after a fluid bolus of crystalloid or colloid using real-time three-dimensional transesophageal echocardiography (3D-TEE and the Vigileo-FloTrac™ system.Materials and methods: After obtaining Institutional Review Board approval, and informed consent from the research participants, 22 patients undergoing scheduled peripheral vascular bypass surgery were enrolled in the study. The patients were randomly assigned to receive 500 mL of hydroxyethyl starch (HES; HES group, n=11 or normal saline (Saline group, n=11 for fluid replacement therapy. SVV was measured using the Vigileo-FloTrac system. LVEDV, stroke volume, and cardiac output were measured by 3D-TEE. The measurements were performed over 30 minutes before and after the fluid bolus in both groups.Results: SVV significantly decreased after fluid bolus in both groups (HES group, 14.7%±2.6% to 6.9%±2.7%, P<0.001; Saline group, 14.3%±3.9% to 8.8%±3.1%, P<0.001. LVEDV significantly increased after fluid loading in the HES group (87.1±24.0 mL to 99.9±27.2 mL, P<0.001, whereas no significant change was detected in the Saline group (88.8±17.3 mL to 91.4±17.6 mL, P>0.05. Stroke volume significantly increased after infusion in the HES group (50.6±12.5 mL to 61.6±19.1 mL, P<0.01 but not in the Saline group (51.6±13.4 mL to 54.1±12.8 mL, P>0.05. Cardiac output measured by 3D-TEE significantly increased in the HES group (3.5±1.1 L/min to 3.9±1.3 L/min, P<0.05, whereas no significant change was seen in the Saline group (3.4±1.1 L/min to 3.3±1.0 L

  7. Two-dimensional color Doppler echocardiography for left ventricular stroke volume assessment: a comparison study with three-dimensional echocardiography.

    Science.gov (United States)

    Silva, Cristina Da; Pedro, Fátima; Deister, Lizandra; Sahlén, Anders; Manouras, Aristomenis; Shahgaldi, Kambiz

    2012-08-01

    Whether measurement of left ventricular outflow tract diameter (LVOTd) using color Doppler (CD) in order to more accurately define LVOTd is more accurate for determination of stroke volume (SV) than gray scale and compare it with direct measurement of LVOT area (a) using three-dimensional echocardiography (3DE) for SV determination. Twenty-one volunteers were examined. LVOTa was calculated by two-dimensional echocardiography (2DE) using the following formula: π× (d/2)(2) , d = LVOT diameter by gray scale and CD, respectively. Planimetry of LVOTa was performed in parasternal long axis using 3DE. Eccentricity Index was calculated using the lateral and anterior-posterior LVOTd. SV was obtained by four different methods: (1) 2D gray scale, (2) 2D color, (3) LVOTa × LVOT velocity time integral, and (4) SV by Simpson's biplane method. Gray scale LVOTd was significantly smaller compared to LVOTd obtained with CD (P vs 3.67 ± 0.70 cm(2) , P vs 3.61 ± 0.89 cm(2) , P = 0.011). Half of the subjects had at least 17% difference between the lateral and anterior-posterior LVOTd. There were significant differences between SV by 2D gray scale and 2D CD (82.8 ± 17.1 mL vs 92.4 ± 16.8 mL, P vs 90.7 ± 19.8 mL, P = 0.025). Our study demonstrates LVOT being frequently elliptical. SV and LVOTa were found to be similar when comparing 2DE CD and 3DE planimetry and showed higher values in comparison to 2DE gray scale, which suggests 2DE CD to be an alternative approach for SV assessment. © 2012, Wiley Periodicals, Inc.

  8. Visual attention in posterior stroke

    DEFF Research Database (Denmark)

    Fabricius, Charlotte; Petersen, Anders; Iversen, Helle K

    Objective: Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere. However, attentional effects of more posterior lesions are less clear. The aim of this study was to characterize visual processing speed...... and apprehension span following posterior cerebral artery (PCA) stroke. We also relate these attentional parameters to visual word recognition, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Methods: Nine patients with MR-verified focal lesions in the PCA......-territory (four left PCA; four right PCA; one bilateral, all >1 year post stroke) were compared to 25 controls using single case statistics. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific speed and span measurements. We also characterized visual field defects...

  9. Deviation of eyes and head in acute cerebral stroke

    Directory of Open Access Journals (Sweden)

    Ilg UJ

    2006-06-01

    Full Text Available Abstract Background It is a well-known phenomenon that some patients with acute left or right hemisphere stroke show a deviation of the eyes (Prévost's sign and head to one side. Here we investigated whether both right- and left-sided brain lesions may cause this deviation. Moreover, we studied the relationship between this phenomenon and spatial neglect. In contrast to previous studies, we determined not only the discrete presence or absence of eye deviation with the naked eye through clinical inspection, but actually measured the extent of horizontal eye-in-head and head-on-trunk deviation. In further contrast, measurements were performed early after stroke onset (1.5 days on average. Methods Eye-in-head and head-on-trunk positions were measured at the bedside in 33 patients with acute unilateral left or right cerebral stroke consecutively admitted to our stroke unit. Results Each single patient with spatial neglect and right hemisphere lesion showed a marked deviation of the eyes and the head to the ipsilesional, right side. The average spontaneous gaze position in this group was 46° right, while it was close to the saggital body midline (0° in the groups with acute left- or right-sided stroke but no spatial neglect as well as in healthy subjects. Conclusion A marked horizontal eye and head deviation observed ~1.5 days post-stroke is not a symptom associated with acute cerebral lesions per se, nor is a general symptom of right hemisphere lesions, but rather is specific for stroke patients with spatial neglect. The evaluation of the patient's horizontal eye and head position thus could serve as a brief and easy way helping to diagnose spatial neglect, in addition to the traditional paper-and-pencil tests.

  10. Visuospatial asymmetry and non-spatial attention in subacute stroke patients with and without neglect

    NARCIS (Netherlands)

    Van Kessel, M.E.; Van Nes, I.J.W.; Brouwer, W.H.; Geurts, A.C.H.; Fasotti, L

    Asymmetry in performance and an association with non-lateralized attention are often mentioned as two important aspects of the clinical manifestation of visuospatial neglect. Both these aspects were investigated in 21 left (LH) and 24 right hemisphere (RH) stroke patients and in 20 healthy subjects.

  11. Left atrial appendage occlusion for stroke prevention in patients with atrial fibrillation: a systematic review and network meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Hanif, Hasib; Belley-Cote, Emilie P; Alotaibi, Abdullah; Dvirnik, Nazari; Neupane, Binod; Beyene, Joseph; Eikelboom, John W; Holmes, David; Whitlock, Richard P

    2018-02-01

    Atrial fibrillation (AF) is one of the leading causes of stroke. Risks associated with oral anticoagulation (OAC) limit adherence to recommended therapy. Left atrial appendage (LAA) occlusion is a treatment alternative in patients with AF. We performed a network meta-analysis (NMA) of randomized trials evaluating the efficacy of LAA occlusion compared with oral anticoagulant, antiplatelet, and placebo for stroke prevention. We also assessed the impact of LAA occlusion on mortality, major bleeding, and operative time. We searched MEDLINE, EMBASE, PubMed, and Cochrane Library for randomized trials comparing percutaneous or surgical LAA occlusion with standard of care in AF patients. Conventional meta-analysis found no difference between groups for stroke (5 trials, 1285 patients;RR 0.78, 95% CI 0.47-1.29), and a significant reduction in mortality (5 trials, 1285 patients; RR 0.71, 95% CI 0.51-0.99) favouring LAA occlusion. NMA demonstrated a trend towards reduction in stroke (OR 0.84, 95% CrI 0.47-1.55) and mortality (OR 0.69, 95% CrI 0.44-1.10) for LAA occlusion versus warfarin, but no statistically significant effect. Statistical ranking curves placed LAA occlusion as the most efficacious treatment on the outcomes of stroke and mortality when compared to warfarin, aspirin, or placebo. No significant differences between groups were seen in major bleeding or operative time for surgical trials. The overall quality of the evidence was low as assessed by GRADE. LAA occlusion appears to preserve the benefits of OAC therapy for stroke prevention in patients with AF, but the current evidence is of low quality.

  12. Serum D-dimer Levels Are Proportionally Associated with Left Atrial Enlargement in Patients with an Acute Ischemic Stroke due to Non-valvular Atrial Fibrillation.

    Science.gov (United States)

    Kim, Tae-Won; Song, In-Uk; Chung, Sung-Woo; Kim, Joong-Seok; Koo, Jaseong; Lee, Kwang-Soo

    2016-01-01

    Objective Left atrial enlargement (LAE) may predispose individuals to blood stasis in atrial fibrillation (AF), and thus play a crucial role in thrombogenesis. The D-dimer level is one of the surrogate markers for a hypercoagulable state and reflects thrombus formation in AF. Since the D-dimer level reflects hypercoagulability as well as thrombus and fibrin burdens, LAE could be associated with a D-dimer elevation. However, no studies have explored this association or which factors contribute to increases in the D-dimer levels in patients with AF. Therefore, we assessed whether the serum D-dimer levels are related to the left atrial volume index (LAVI) or other vascular risk factors and also evaluated the association between the D-dimer levels and the initial stroke severity. Methods Ninety-eight consecutive patients with an acute ischemic stroke and non-valvular AF (NVAF) who were anticoagulation-naïve were enrolled, and all patients were stratified into moderate-to-severe and mild neurologic deficit groups using the National Institutes of Health Stroke Scale on admission. The association between the initial serum D-dimer levels and the LAVI was evaluated in all enrolled patients, and the serum D-dimer levels were compared between the two groups. Results The patients were classified into two groups according to the severity of the neurologic deficit. In a partial correlation coefficient analysis adjusted for confounding factors, an increase in the initial serum D-dimer levels was significantly associated with LAVI (r=0.286; p=0.027). A linear regression analysis showed that a history of peripheral artery disease was the factor most strongly associated with the serum D-dimer level (t=3.90, pacute ischemic stroke and NVAF.

  13. How to engage the right brain hemisphere in aphasics without even singing: evidence for two paths of speech recovery

    OpenAIRE

    Stahl, Benjamin; Henseler, Ilona; Turner, Robert; Geyer, Stefan; Kotz, Sonja A.

    2013-01-01

    There is an ongoing debate as to whether singing helps left-hemispheric stroke patients recover from non-fluent aphasia through stimulation of the right hemisphere. According to recent work, it may not be singing itself that aids speech production in non-fluent aphasic patients, but rhythm and lyric type. However, the long-term effects of melody and rhythm on speech recovery are largely unknown. In the current experiment, we tested 15 patients with chronic non-fluent aphasia who underwent eit...

  14. Change in pulse pressure/stroke index in response to sustained blood pressure reduction and its impact on left ventricular mass and geometry changes: the life study

    DEFF Research Database (Denmark)

    Palmieri, V.; Bella, J.N.; Gerdts, E.

    2008-01-01

    in hypertension (LIFE) study, we evaluated the impact of antihypertensive treatment on change of PP/SVi as raw indicator of systemic arterial stiffness, and further explored the impact of the change in PP/SVi on the change in LV mass and RWT. RESULTS: Compared to baseline, mean PP/SVi reduction was -13% at year 1......BACKGROUND: In cross-sectional data in hypertensive subjects, brachial pulse pressure (PP)/Doppler stroke index (SVi), (PP/SVi) correlates weakly but significantly with left ventricular (LV) mass and relative wall thickness (RWT). METHODS: In the Losartan Intervention For End-point reduction...

  15. Late stroke: comparison of percutaneous coronary intervention versus coronary artery bypass grafting in patients with multivessel disease and unprotected left main disease: a meta-analysis and review of literature.

    Science.gov (United States)

    Athappan, Ganesh; Chacko, Paul; Patvardhan, Eshan; Gajulapalli, Rama Dilip; Tuzcu, Emin Murat; Kapadia, Samir R

    2014-01-01

    Studies have suggested that the early excess risk of stroke in coronary artery bypass grafting (CABG) may be compensated for by a slow but progressive catch-up phenomenon in patients undergoing percutaneous coronary intervention (PCI). We therefore undertook this analysis to compare the temporal stroke risk between PCI and CABG in patients with unprotected left main stenosis and multivessel coronary artery disease. Studies of PCI versus CABG for unprotected left main stenosis and multivessel disease published between January 1994 (stent era) and July 2013 were identified using an electronic search and reviewed using meta-analytic techniques. We selected 57 reports for the meta-analysis by applying the inclusion and exclusion criteria. The analysis was performed on 80,314 patient records. There was a significantly lower risk of cumulative stroke in patients undergoing PCI with stenting at 1 year (odds ratio [OR], 0.55; 95% confidence interval [CI], 0.42-0.71), 2 years (OR, 0.78; 95% CI, 0.66-0.92), 3 years (OR, 0.79; 95% CI, 0.67-0.92), 4 years (OR, 0.74; 95% CI, 0.56-0.97), and 5 years (OR, 0.79; 95% CI, 0.69-0.91). There was no significant difference in the incidence of stroke because of the small sample size (OR, 0.71; 95% CI, 0.46-1.08) at >5 years between PCI and CABG. Similar results were observed on subgroup analysis (multi-vessel coronary artery disease, unprotected left main, diabetics, and randomized trials) and for stroke within 30 days. Late stroke (stroke>30 days) was similar between the 2 groups. There is a significantly lower risk of stroke within 30 days and cumulative stroke with PCI as compared with CABG up to year 5. There is no late catch up of stroke in the PCI arm. The risk of stroke should be weighed in deciding between revascularization strategies.

  16. Diagnostic Accuracy of the Barthel Index for Measuring Activities of Daily Living Outcome After Ischemic Hemispheric Stroke Does Early Poststroke Timing of Assessment Matter?

    NARCIS (Netherlands)

    Kwakkel, Gert; Veerbeek, Janne M.; Harmeling-van der Wel, Barbara C.; van Wegen, Erwin; Kollen, Boudewijn J.; Harmeling-van der Wel, BC

    Background and Purpose-This study investigated the diagnostic accuracy of the Barthel Index (BI) in 206 stroke patients, measured within 72 hours, for activities of daily living at 6 months and determined whether the timing of BI assessment during the first days affects the accuracy of predicting

  17. Brain Stimulation and the Role of the Right Hemisphere in Aphasia Recovery.

    Science.gov (United States)

    Turkeltaub, Peter E

    2015-11-01

    Aphasia is a common consequence of left hemisphere stroke and causes a disabling loss of language and communication ability. Current treatments for aphasia are inadequate, leaving a majority of aphasia sufferers with ongoing communication difficulties for the rest of their lives. In the past decade, two forms of noninvasive brain stimulation, repetitive transcranial magnetic stimulation and transcranial direct current stimulation, have emerged as promising new treatments for aphasia. The most common brain stimulation protocols attempt to inhibit the intact right hemisphere based on the hypothesis that maladaptive activity in the right hemisphere limits language recovery in the left. There is now sufficient evidence to demonstrate that this approach, at least for repetitive transcranial magnetic stimulation, improves specific language abilities in aphasia. However, the biological mechanisms that produce these behavioral improvements remain poorly understood. Taken in the context of the larger neurobiological literature on aphasia recovery, the role of the right hemisphere in aphasia recovery remains unclear. Additional research is needed to understand biological mechanisms of recovery, in order to optimize brain stimulation treatments for aphasia. This article summarizes the current evidence on noninvasive brain stimulation methods for aphasia and the neuroscientific considerations surrounding treatments using right hemisphere inhibition. Suggestions are provided for further investigation and for clinicians whose patients ask about brain stimulation treatments for aphasia.

  18. Right ventricular longitudinal strain and right ventricular stroke work index in patients with severe heart failure: left ventricular assist device suitability for transplant candidates.

    Science.gov (United States)

    Cameli, M; Bernazzali, S; Lisi, M; Tsioulpas, C; Croccia, M G; Lisi, G; Maccherini, M; Mondillo, S

    2012-09-01

    Right ventricular (RV) systolic function has a critical role in determining the clinical outcome and the success of using left ventricular assist devices in patients with refractory heart failure. RV deformation analysis by speckle tracking echocardiography (STE) has recently allowed the analysis of RV longitudinal function. Using cardiac catheterization as the reference standard, this study aimed to explore the correlation between RV longitudinal function by STE and RV stroke work index (RVSWI) among patients referred for cardiac transplantation. Right heart catheterization and transthoracic echo-Doppler were simultaneously performed in 47 patients referred for cardiac transplant assessment due to refractory heart failure (ejection fraction 25.1 ± 4.5%). Thermodilution RV stroke volume and invasive pulmonary pressures were used to obtain RVSWI. RV longitudinal strain (RVLS) by STE was assessed averaging RV free-wall segments (free-wall RVLS). We also calculated. Tricuspid S' and tricuspid annular plane systolic excursion (TAPSE). No significant correlation was observed for TAPSE on tricuspid S' with RV stroke volume (r = 0.14 and r = 0.06, respectively). A close negative correlation between free-wall RVLS and RVSWI was found (r = -0.82; P rights reserved.

  19. Influence of surgical implantation angle of left ventricular assist device outflow graft and management of aortic valve opening on the risk of stroke in heart failure patients

    Science.gov (United States)

    Chivukula, V. Keshav; McGah, Patrick; Prisco, Anthony; Beckman, Jennifer; Mokadam, Nanush; Mahr, Claudius; Aliseda, Alberto

    2016-11-01

    Flow in the aortic vasculature may impact stroke risk in patients with left ventricular assist devices (LVAD) due to severely altered hemodynamics. Patient-specific 3D models of the aortic arch and great vessels were created with an LVAD outflow graft at 45, 60 and 90° from centerline of the ascending aorta, in order to understand the effect of surgical placement on hemodynamics and thrombotic risk. Intermittent aortic valve opening (once every five cardiac cycles) was simulated and the impact of this residual native output investigated for the potential to wash out stagnant flow in the aortic root region. Unsteady CFD simulations with patient-specific boundary conditions were performed. Particle tracking for 10 cardiac cycles was used to determine platelet residence times and shear stress histories. Thrombosis risk was assessed by a combination of Eulerian and Lagrangian metrics and a newly developed thrombogenic potential metric. Results show a strong influence of LVAD outflow graft angle on hemodynamics in the ascending aorta and consequently on stroke risk, with a highly positive impact of aortic valve opening, even at low frequencies. Optimization of LVAD implantation and management strategies based on patient-specific simulations to minimize stroke risk will be presented

  20. Ressecção de mixoma ventricular esquerdo após acidente vascular cerebral embólico Resection of left ventricular myxoma after embolic stroke

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Ferraz de Arruda

    2008-12-01

    Full Text Available Mixoma cardíaco é o tumor primário mais comum do coração. Sua principal localização é no átrio esquerdo, mas pode surgir em qualquer câmara cardíaca. Os sintomas clínicos são variáveis, mas dispnéia e embolia são os mais freqüentes. Relatamos o caso de um jovem com acidente vascular cerebral isquêmico embólico causado por um grande mixoma no ventrículo esquerdo. O paciente foi submetido a cirurgia três semanas após o acidente vascular cerebral. O tumor foi ressecado com cuidado, sem fragmentar. O tratamento cirúrgico foi eficaz. Enfatizamos a raridade da presente localização, juntamente com uma revisão da literatura atual.Cardiac myxoma is the most common primary tumor of the heart. The tumor is located mainly in the left atrium but can arise from any heart chamber. Clinical symptoms are variable but dyspnea and embolism are the most frequent. We report a case of a young man that had embolic ischemic stroke caused by a large left ventricular myxoma. The patient underwent surgery three weeks after the stroke. The tumor was carefully resected without fragmentation. Surgical treatment was effective. We emphasize the rarity of this location together with a review of the current literature.

  1. [Visual dependence after recent stroke].

    Science.gov (United States)

    Bonan, I; Derighetti, F; Gellez-Leman, M-C; Bradaï, N; Yelnik, A

    2006-05-01

    After chronic stroke, inability to use pertinent somatosensory or vestibular information have been described. The aim of the study was to determine whether visual dependence occurred early after stroke before rehabilitation. Thirty patients with recent hemiplegia (16 right and 14 left hemispheric stroke) performed the rod and frame test (RFT). Patients were asked to adjust the rod to the vertical position under 3 conditions: basically, with a frame tilted 18 degrees to the right and then with the frame tilted to the left. Bias in each condition (mean, SD) was recorded and compared to adjustments of the rod by 23 controls. Motor control, sensibility, functional level (functional independence measure), age, neglect, and then balance by the postural assessment scale for stroke were assessed. Fifty-six per cent (17/30) of patients but only 26% of controls were influenced by the tilt of the frame on the 2 sides (visual dependence). No correlation was found between visual dependence and the characteristics of the patients. Many patients with recent hemiplegia seem to rely on visual input. The mechanisms of such visual dependence are discussed. Rehabilitation programs should take into account the possible impairment of sensory organisation and should include exercises to be performed under visual disturbances.

  2. Left Atrial Appendage Occlusion Device and Novel Oral Anticoagulants Versus Warfarin for Stroke Prevention in Nonvalvular Atrial Fibrillation: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Briceno, David F; Villablanca, Pedro; Cyrille, Nicole; Massera, Daniele; Bader, Eric; Manheimer, Eric; Aagaard, Philip; Ferrick, Kevin; Gross, Jay; Kim, Soo Gyum; Krumerman, Andrew; Palma, Eugen; Guttenplan, Nils; Romero, Jorge; Fisher, John; Garcia, Mario; Natale, Andrea; Di Biase, Luigi

    2015-10-01

    Nonvalvular atrial fibrillation is the most common arrhythmia. Patients with nonvalvular atrial fibrillation are at increased risk of stroke; therefore, we evaluated the efficacy and safety of different approaches to prevent this major complication. We conducted electronic database searches of phase III randomized controlled trials. The groups were novel oral anticoagulants, Watchman left atrial appendage occlusion device (DEVICE), and warfarin. Efficacy outcomes were stroke or systemic embolism, and all-cause mortality. Safety outcome was major bleeding and procedure-related complications. A subgroup analysis of the elderly population was done. We used random-effects model to compare pooled outcomes and tested for heterogeneity. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed for each outcome. Seven randomized controlled trials (n=73,978) were included. There was a significant difference favoring novel oral anticoagulants for systemic embolism (OR, 0.84; 95% CI, 0.72-0.97; P=0.01), all-cause mortality (OR, 0.89; 95% CI, 0.84-0.94; P<0.001), and safety outcomes (OR, 0.79; 95% CI, 0.65-0.97; P=0.026) compared with warfarin. No difference was seen between DEVICE and warfarin for efficacy end points; however, DEVICE had more complications (OR, 1.85; 95% CI, 1.14-3.01; P=0.012). In the elderly (6 randomized controlled trials, n=30,699), systemic embolism was favored with novel oral anticoagulants over warfarin (OR, 0.77; 95% CI, 0.68-0.87; P≤0.001). No evidence of significant publication bias was found. Novel oral anticoagulants is superior to warfarin for stroke prevention in nonvalvular atrial fibrillation. This benefit was also observed in the elderly population. DEVICE is a reasonable noninferior alternative to warfarin for stroke prevention, but cautious use is essential given safety concerns. © 2015 American Heart Association, Inc.

  3. Different plasticity patterns of language function in children with perinatal and childhood stroke.

    Science.gov (United States)

    Ilves, Pilvi; Tomberg, Tiiu; Kepler, Joosep; Laugesaar, Rael; Kaldoja, Mari-Liis; Kepler, Kalle; Kolk, Anneli

    2014-06-01

    Plasticity of language function after brain damage can depend on maturation of the brain. Children with left-hemisphere perinatal (n = 7) or childhood stroke (n = 5) and 12 controls were investigated using functional magnetic resonance imaging. The verb generation and the sentence comprehension tasks were employed to activate the expressive and receptive language areas, respectively. Weighted laterality indices were calculated and correlated with results assessed by neuropsychological test battery. Compared to controls, children with childhood stroke showed significantly lower mean scores for the expressive (P children with perinatal and childhood stroke and correlates with neurocognitive performance. © The Author(s) 2013.

  4. Unexpected Improvement of Hand Motor Function with a Left Temporoparietal Low-Frequency Repetitive Transcranial Magnetic Stimulation Regime Suppressing Auditory Hallucinations in a Brainstem Chronic Stroke Patient

    Directory of Open Access Journals (Sweden)

    Fanny Thomas

    2017-11-01

    Full Text Available We here report paradoxical hand function recovery in a 61-year-old male tetra-paretic chronic patient following a stroke of the brainstem (with highly degraded right and abolished left-hand finger flexion/extension disabling him to manipulate objects who experienced insidious auditory hallucinations (AHs 4 years after such event. Symptomatic treatment for AHs was provided with periodical double sessions of low-frequency repetitive transcranial magnetic stimulation (rTMS (daily 1 Hz, 2 × 1,200 pulses interleaved by 1 h interval delivered to the left temporoparietal junction across two periods of 5 and 3 weeks, respectively. At the end of each stimulation period, AHs disappeared completely. Most surprisingly and totally unexpectedly, the patient experienced beneficial improvements of long-lasting impairments in his right-hand function. Detailed examination of onset and offset of rTMS stimulation regimes strongly suggests a temporal relation with the remission and re-appearance of AHs and also with a fragile but clinically meaningful improvements of right (but not left hand function contingent to the accrual of stimulation sessions. On the basis of post-recovery magnetic resonance imaging structural and functional evidence, mechanistic hypotheses that could subtend such unexpected motor recovery are critically discussed.

  5. A semi-Markov model for stroke with piecewise-constant hazards in the presence of left, right and interval censoring.

    Science.gov (United States)

    Kapetanakis, Venediktos; Matthews, Fiona E; van den Hout, Ardo

    2013-02-20

    This paper presents a parametric method of fitting semi-Markov models with piecewise-constant hazards in the presence of left, right and interval censoring. We investigate transition intensities in a three-state illness-death model with no recovery. We relax the Markov assumption by adjusting the intensity for the transition from state 2 (illness) to state 3 (death) for the time spent in state 2 through a time-varying covariate. This involves the exact time of the transition from state 1 (healthy) to state 2. When the data are subject to left or interval censoring, this time is unknown. In the estimation of the likelihood, we take into account interval censoring by integrating out all possible times for the transition from state 1 to state 2. For left censoring, we use an Expectation-Maximisation inspired algorithm. A simulation study reflects the performance of the method. The proposed combination of statistical procedures provides great flexibility. We illustrate the method in an application by using data on stroke onset for the older population from the UK Medical Research Council Cognitive Function and Ageing Study. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Acupuncture at Waiguan (TE5) influences activation/deactivation of functional brain areas in ischemic stroke patients and healthy people: A functional MRI study☆

    Science.gov (United States)

    Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Zeng, Tongjun; Wu, Junxian; Qu, Shanshan

    2013-01-01

    In the present study, 10 patients with ischemic stroke in the left hemisphere and six healthy controls were subjected to acupuncture at right Waiguan (TE5). In ischemic stroke subjects, functional MRI showed enhanced activation in Broadmann areas 5, 6, 7, 18, 19, 24, 32, the hypothalamic inferior lobe, the mamillary body, and the ventral posterolateral nucleus of the left hemisphere, and Broadmann areas 4, 6, 7, 18, 19 and 32 of the right hemisphere, but attenuated activation of Broadmann area 13, the hypothalamic inferior lobe, the posterior lobe of the tonsil of cerebellum, and the culmen of the anterior lobe of hypophysis, in the left hemisphere and Broadmann area 13 in the right hemisphere. In ischemic stroke subjects, a number of deactivated brain areas were enhanced, including Broadmann areas 6, 11, 20, 22, 37, and 47, the culmen of the anterior lobe of hypophysis, alae lingulae cerebella, and the posterior lobe of the tonsil of cerebellum of the left hemisphere, and Broadmann areas 8, 37, 45 and 47, the culmen of the anterior lobe of hypophysis, pars tuberalis adenohypophyseos, inferior border of lentiform nucleus, lateral globus pallidus, inferior temporal gyrus, and the parahippocampal gyrus of the right hemisphere. These subjects also exhibited attenuation of a number of deactivated brain areas, including Broadmann area 7. These data suggest that acupuncture at Waiguan specifically alters brain function in regions associated with sensation, vision, and motion in ischemic stroke patients. By contrast, in normal individuals, acupuncture at Waiguan generally activates brain areas associated with insomnia and other functions. PMID:25206592

  7. Usefulness of left ventricular speckle tracking echocardiography and novel measures of left atrial structure and function in diagnosing paroxysmal atrial fibrillation in ischemic stroke and transient ischemic attack patients.

    Science.gov (United States)

    Skaarup, Kristoffer Grundtvig; Christensen, Hanne; Høst, Nis; Mahmoud, Masti Mahdy; Ovesen, Christian; Olsen, Flemming Javier; Jensen, Jan Skov; Biering-Sørensen, Tor

    2017-12-01

    Asymptomatic paroxysmal atrial fibrillation (PAF) is often assumed to be the cause of cryptogenic ischemic strokes (IS) and transient ischemic attacks (TIA). We examined the usefulness of measures obtained by 2D speckle tracking echocardiography and novel left atrial measurements, in the diagnosis of PAF in patients with IS and TIA. We retrospectively included 205 patients who after acute IS or TIA underwent an echocardiogram in sinus rhythm. Patients were designated as PAF-patients if they had one or more reported incidents of AF before or after their echocardiographic examination. None of the conventional echocardiographic parameters were significantly associated with PAF. Of the speckle tracking measurements, only early diastolic strain rate (0.7±0.2 s -1 vs. 0.8±0.3 s -1 , p = 0.048) and global longitudinal displacement (GLD) (3.15 ± 1.40 mm vs. 3.87 ± 1.56 mm, p = 0.007) proved significantly different. Of the left atrial parameters both minimal and maximal left atrium volume divided by left ventricular length (min LAV/LVL and max LAV/LVL, respectively) were significantly impaired (min LAV/LVL: 3.7 ± 2.1 cm 2 vs. 2.8 ± 1.11 cm 2 , p = 0.012; max LAV/LVL: 6.6 ± 3.1 cm 2 vs. 5.6 ± 1.7 cm 2 , p = 0.012). GLD, min max LAV/LVL proved significant after adjustment for age, gender, CHA 2 DS 2 -VASc and NIHSS. By combining information regarding age, GLD, min and max LAV/LVL the diagnostic accuracy of PAF improved, resulting in a significantly increased area under the curve (p = 0.037). In patients with IS and TIA GLD, min and max LAV/LVL were independently associated with the presence of PAF.

  8. Verbal short-term memory and language impairments in Cantonese speakers after stroke.

    Science.gov (United States)

    Ho, Diana Wai-Lam; Kong, Anthony Pak-Hin; Koon, Nim-Ting

    2017-02-21

    The study examined the relationship between verbal short-term memory (STM) and language impairment in Cantonese speakers after stroke. It is hypothesised that Cantonese speakers with left-hemisphere (LH) stroke would perform worse than those with right hemisphere (RH) stroke and normal controls. Specific linguistic factors of Cantonese might affect results in the tasks. Fifteen participants with LH stroke, 10 with RH stroke and 25 healthy controls were tested with auditory-verbal immediate serial recall (ISR) tasks and auditory linguistic tasks. All stroke participants were assessed with the Cantonese version of Western Aphasia Battery (CAB). The LH group performed significantly worse than the RH and healthy control groups in the auditory verbal ISR and auditory linguistic tasks. There were significant lexicality, frequency and imageability effects in most tasks. Auditory discrimination and word comprehension tasks, but not the auditory word recognition task had correlations with ISR tasks. Verbal STM and language performance of Cantonese-speakers with history of LH stroke were inferior to RH stroke and healthy controls. The effects of lexicality, word frequency and imageability on verbal STM memory performance were found. Cantonese tones have effects on performance in auditory word recognition task, similar to onset, nucleus and rime.

  9. Risk factors for swallowing dysfunction in stroke patients

    Directory of Open Access Journals (Sweden)

    Anna Flávia Ferraz Barros Baroni

    2012-06-01

    Full Text Available CONTEXT: Stroke is a frequent cause of dysphagia. OBJECTIVE: To evaluate in a tertiary care hospital the prevalence of swallowing dysfunction in stroke patients, to analyze factors associated with the dysfunction and to relate swallowing dysfunction to mortality 3 months after the stroke. METHODS: Clinical evaluation of deglutition was performed in 212 consecutive patients with a medical and radiologic diagnosis of stroke. The occurrence of death was determined 3 months after the stroke. RESULTS: It was observed that 63% of the patients had swallowing dysfunction. The variables gender and specific location of the lesion were not associated with the presence or absence of swallowing dysfunction. The patients with swallowing dysfunction had more frequently a previous stroke, had a stroke in the left hemisphere, motor and/or sensitivity alterations, difficulty in oral comprehension, alteration of oral expression, alteration of the level of consciousness, complications such as fever and pneumonia, high indexes on the Rankin scale, and low indexes on the Barthel scale. These patients had a higher mortality rate. CONCLUSIONS: Swallowing evaluation should be done in all patients with stroke, since swallowing dysfunction is associated with complications and an increased risk of death.

  10. Left ventricular systolic dysfunction, heart failure, and the risk of stroke and systemic embolism in patients with atrial fibrillation: insights from the ARISTOTLE trial.

    Science.gov (United States)

    McMurray, John J V; Ezekowitz, Justin A; Lewis, Basil S; Gersh, Bernard J; van Diepen, Sean; Amerena, John; Bartunek, Jozef; Commerford, Patrick; Oh, Byung-Hee; Harjola, Veli-Pekka; Al-Khatib, Sana M; Hanna, Michael; Alexander, John H; Lopes, Renato D; Wojdyla, Daniel M; Wallentin, Lars; Granger, Christopher B

    2013-05-01

    We examined the risk of stroke or systemic embolism (SSE) conferred by heart failure (HF) and left ventricular systolic dysfunction (LVSD) in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation Trial (ARISTOTLE), as well as the effect of apixaban versus warfarin. The risk of a number of outcomes, including the composite of SSE or death (to take account of competing risks) and composite of SSE, major bleeding, or death (net clinical benefit) were calculated in 3 patient groups: (1) no HF/no LVSD (n=8728), (2) HF/no LVSD (n=3207), and (3) LVSD with/without symptomatic HF (n=2736). The rate of both outcomes was highest in patients with LVSD (SSE or death 8.06; SSE, major bleeding, or death 10.46 per 100 patient-years), intermediate for HF but preserved LV systolic function (5.32; 7.24), and lowest in patients without HF or LVSD (1.54; 5.27); each comparison PARISTOTLE patients, the apixaban/warfarin hazard ratio for SSE or death was 0.89 (95% confidence interval, 0.81-0.98; P=0.02); for SSE, major bleed, or death it was 0.85 (0.78-0.92; P<0.001). There was no heterogeneity of treatment effect across the 3 groups. Patients with LVSD (with/without HF) had a higher risk of SSE or death (but similar rate of SSE) compared with patients with HF but preserved LV systolic function; both had a greater risk than patients without either HF or LVSD. Apixaban reduced the risk of both outcomes more than warfarin in all 3 patient groups. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00412984.

  11. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output

    DEFF Research Database (Denmark)

    Smerup, Morten; Damkjær, Mads; Brøndum, Emil Toft

    2016-01-01

    Giraffes--the tallest extant animals on Earth--are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. Arterial pressure may exceed 300 mmHg and has historically been attributed to an exceptionally large heart. Recently, this has been refuted...... by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It thus remains unexplained how the normal-sized giraffe heart generates such massive arterial pressures. We hypothesized that giraffe hearts have a small intraventricular...... cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic pressures...

  12. Intra-Arterial Treatment in a Child with Embolic Stroke Due to Atrial Myxoma

    Science.gov (United States)

    van den Wijngaard, Ido; Wermer, Marieke; van Walderveen, Marianne; Wiendels, Natalie; Peeters-Scholte, Cacha; Lycklama à Nijeholt, Geert

    2014-01-01

    Summary Arterial ischaemic stroke is an important cause of morbidity in children. Timely diagnosis is necessary for acute stroke treatment but can be challenging in clinical practice. Due to a paucity of data there are no specific recommendations regarding the use of mechanical thrombectomy devices in current paediatric stroke guidelines. A 14-year-old boy presented with a severe acute left hemisphere stroke due to a proximal middle cerebral artery occlusion caused by emboli from an atrial myxoma. No clinical improvement was seen after administration of intravenous thrombolysis. Subsequent mechanical thrombectomy with a second-generation stent-based thrombectomy device resulted in successful recanalization and clinical improvement. To our knowledge, this is the first report of mechanical thrombectomy in a child with acute embolic stroke caused by atrial myxoma. PMID:24976098

  13. Concurrence of Crossed Cerebellar Diaschisis and Parakinesia Brachialis Oscitans in a Patient with Hemorrhagic Stroke

    Directory of Open Access Journals (Sweden)

    Yung-Tsan Wu

    2013-01-01

    Full Text Available Crossed cerebellar diaschisis (CCD is defined as a reduction in blood flow in the cerebellar hemisphere contralateral to the supratentorial focal lesion. The phenomenon termed parakinesia brachialis oscitans (PBO in which stroke patients experience involuntary stretching of the hemiplegic arm during yawning is rarely reported. The concurrence of CCD and PBO has never been described. A 52-year-old man had putaminal hemorrhage and demonstrated no significant recovery in his left hemiplegia after intensive rehabilitation, but his gait improved gradually. Two months after the stroke, the single photon emission computed tomography (SPECT showed CCD. Four months after the stroke, the patient noticed PBO. The follow-up SPECT showed persistent CCD and the patient’s arm was still plegic. The frequency and intensity of PBO have increased with time since the stroke. We speculate that the two phenomena CCD and PBO might share similar neuroanatomical pathways and be valuable for predicting clinical recovery after stroke.

  14. Improvement of Upper Extremity Deficit after Constraint-Induced Movement Therapy Combined with and without Preconditioning Stimulation Using Dual-hemisphere Transcranial Direct Current Stimulation and Peripheral Neuromuscular Stimulation in Chronic Stroke Patients: A Pilot Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Takashi Takebayashi

    2017-10-01

    Full Text Available In this study, we investigated the effects of dual-hemisphere transcranial direct current stimulation (dual-tDCS of both the affected (anodal tDCS and non-affected (cathodal tDCS primary motor cortex, combined with peripheral neuromuscular electrical stimulation (PNMES, on the effectiveness of constraint-induced movement therapy (CIMT as a neurorehabilitation intervention in chronic stroke. We conducted a randomized controlled trial of feasibility, with a single blind assessor, with patients recruited from three outpatient clinics. Twenty chronic stroke patients were randomly allocated to the control group, receiving conventional CIMT, or the intervention group receiving dual-tDCS combined with PNMES before CIMT. Patients in the treatment group first underwent a 20-min period of dual-tDCS, followed immediately by PNMES, and subsequent CIMT for 2 h. Patients in the control group only received CIMT (with no pretreatment stimulation. All patients underwent two CIMT sessions, one in the morning and one in the afternoon, each lasting 2 h, for a total of 4 h of CIMT per day. Upper extremity function was assessed using the Fugl-Meyer Assessment (primary outcome, as well as the amount of use (AOU and quality of movement (QOM scores, obtained via the Motor Activity Log (secondary outcome. Nineteen patients completed the study, with one patient withdrawing after allocation. Compared to the control group, the treatment improvement in upper extremity function and AOU was significantly greater in the treatment than control group (change in upper extremity score, 9.20 ± 4.64 versus 4.56 ± 2.60, respectively, P < 0.01, η2 = 0.43; change in AOU score, 1.10 ± 0.65 versus 0.62 ± 0.85, respectively, P = 0.02, η2 = 0.52. There was no significant effect of the intervention on the QOM between the intervention and control groups (change in QOM score, 1.00 ± 0.62 versus 0.71 ± 0.72, respectively, P = 0.07, η2

  15. Left atrial appendage morphology assessment for risk stratification of embolic stroke in patients with atrial fibrillation: A meta-analysis.

    Science.gov (United States)

    Lupercio, Florentino; Carlos Ruiz, Juan; Briceno, David F; Romero, Jorge; Villablanca, Pedro A; Berardi, Cecilia; Faillace, Robert; Krumerman, Andrew; Fisher, John D; Ferrick, Kevin; Garcia, Mario; Natale, Andrea; Di Biase, Luigi

    2016-07-01

    Thromboembolic event (TE) risk stratification is performed by using CHA2DS2VASc score. It has been suggested that left atrial appendage (LAA) morphology independently influences TE risk in patients with nonvalvular atrial fibrillation. LAA morphology has been classified into 4 types: chicken wing, cauliflower, windsock, and cactus. The purpose of this study was to determine TE risk for each LAA morphology in patients with atrial fibrillation with low to intermediate TE risk. A systematic review of MEDLINE, Cochrane Library, and Embase for studies that used computed tomography, tridimensional transesophageal echocardiography, and cardiac magnetic resonance imaging to categorize the LAA morphologies with assessment of TE prevalence. Odds ratio (OR) and 95% confidence intervals (CIs) were measured using the Mantel-Haenszel method. The fixed effects model was used, and if heterogeneity (I2) was >25%, effects were analyzed using a random model. Eight studies with 2596 patients were included. Eighty-four percent (n=1872) of patients had a CHADS2 score of <2. TE risk was lower in chicken wing morphology than in non-chicken wing morphology (OR 0.46; 95% CI 0.36-0.58). Likewise, chicken wing morphology had lower TE risk than did other morphologies (chicken wing vs cauliflower: OR 0.38; 95% CI 0.26-0.56; chicken wing vs windsock: OR 0.48; 95% CI 0.31-0.73; chicken wing vs cactus: OR 0.49; 95% CI 0.36-0.66). Patients with chicken wing LAA morphology are less likely to develop TE than patients with non-chicken wing morphology. LAA morphology may be a valuable criterion in predicting TE and could affect the stratification and anticoagulation management of patients with low to intermediate TE risk. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  16. Modality-Dependent or Modality-Independent Processing in Mental Arithmetic: Evidence From Unimpaired Auditory Multiplication for a Patient With Left Frontotemporal Stroke.

    Science.gov (United States)

    Cheng, Dazhi; Wu, Haiyan; Yuan, Li; Xu, Rui; Chen, Qian; Zhou, Xinlin

    2017-09-01

    Mental arithmetic is essential to daily life. Researchers have explored the mechanisms that underlie mental arithmetic. Whether mental arithmetic fact retrieval is dependent on surface modality or knowledge format is still highly debated. Chinese individuals typically use a procedure strategy for addition; and they typically use a rote verbal strategy for multiplication. This provides a way to examine the effect of surface modality on different arithmetic operations. We used a series of neuropsychological tests (i.e., general cognitive, language processing, numerical processing, addition, and multiplication in visual and auditory conditions) for a patient who had experienced a left frontotemporal stroke. The patient had language production impairment; but preserved verbal processing concerning basic numerical abilities. Moreover, the patient had preserved multiplication in the auditory presentation rather than in the visual presentation. The patient suffered from impairments in an addition task, regardless of visual or auditory presentation. The findings suggest that mental multiplication could be characterized as a form of modality-dependent processing, which was accessed through auditory input. The learning strategy of multiplication table recitation could shape the verbal memory of multiplication leading to persistence of the auditory module. (JINS, 2017, 23, 692-699).

  17. Assessment of left atrial appendage function by transthoracic pulsed Doppler echocardiography: Comparing against transesophageal interrogation and predicting echocardiographic risk factors for stroke.

    Science.gov (United States)

    Wai, Shin Hnin; Kyu, Kyu; Galupo, Mary Joyce; Songco, Geronica G; Kong, William K F; Lee, Chi Hang; Yeo, Tiong Cheng; Poh, Kian Keong

    2017-10-01

    Transesophageal echocardiographic (TEE) findings of left atrial appendage (LAA) thrombus, spontaneous echo contrast (SEC), and LAA dysfunction are established risk factors of cardioembolic stroke. The semi-invasive nature of TEE limits its utility as a routine risk stratification tool. We aim to correlate TEE and transthoracic echocardiography (TTE) pulsed Doppler measurements of LAA flow velocities and use TTE measurements to predict TEE findings. We prospectively measured pulsed Doppler LAA flow velocities in 103 consecutive patients on TEE and TTE. There was a strong correlation between TEE and TTE LAA emptying velocity (LAA E) (r = .88, P TTE LAA E predicted the presence of thrombus or SEC independent of atrial fibrillation (AF). To predict the presence of thrombus or SEC, the optimal TTE LAA E cutoff was ≤30 cm/s in all patients (75% sensitive, 90% specific) and ≤31 cm/s in AF patients (80% sensitive, 79% specific). To predict LAA dysfunction (TEE E ≤ 20 cm/s), the optimal TTE LAA E cutoff was ≤27 cm/s (100% sensitive, 89% specific in all patients and 100% sensitive, 74% specific in AF patients). TTE assessment of LAA function is feasible and correlates well with the more invasive TEE method. It predicts the presence of thrombus, SEC, and LAA dysfunction on TEE. TTE LAA assessment has incremental value in thromboembolic risk stratification and should be utilized more frequently. © 2017, Wiley Periodicals, Inc.

  18. Perturbation of the left inferior frontal gyrus triggers adaptive plasticity in the right homologous area during speech production

    DEFF Research Database (Denmark)

    Hartwigsen, Gesa; Saur, Dorothee; Price, Cathy J

    2013-01-01

    The role of the right hemisphere in aphasia recovery after left hemisphere damage remains unclear. Increased activation of the right hemisphere has been observed after left hemisphere damage. This may simply reflect a release from transcallosal inhibition that does not contribute to language...... hemisphere lesion. Our findings lend further support to the notion that increased activation of homologous right hemisphere areas supports aphasia recovery after left hemisphere damage....

  19. Rehabilitation of limb apraxia improves daily life activities in patients with stroke.

    Science.gov (United States)

    Smania, N; Aglioti, S M; Girardi, F; Tinazzi, M; Fiaschi, A; Cosentino, A; Corato, E

    2006-12-12

    We randomly assigned 33 patients with left hemisphere stroke, limb apraxia, and aphasia to an apraxia or a control (aphasia) treatment group. Before and after each treatment, patients underwent a comprehensive neuropsychological testing battery and a caregiver evaluation of patient's activities of daily life (ADL) independence. Apraxia severity was related with ADL independence. Control (aphasia) treatment improved patients' language and intelligence performance. Apraxia treatment specifically improved praxic function and ADL.

  20. Altered resting-state network connectivity in stroke patients with and without apraxia of speech

    OpenAIRE

    New, Anneliese B.; Robin, Donald A.; Parkinson, Amy L.; Duffy, Joseph R.; McNeil, Malcom R.; Piguet, Olivier; Hornberger, Michael; Price, Cathy J.; Eickhoff, Simon B.; Ballard, Kirrie J.

    2015-01-01

    Motor speech disorders, including apraxia of speech (AOS), account for over 50% of the communication disorders following stroke. Given its prevalence and impact, and the need to understand its neural mechanisms, we used resting state functional MRI to examine functional connectivity within a network of regions previously hypothesized as being associated with AOS (bilateral anterior insula (aINS), inferior frontal gyrus (IFG), and ventral premotor cortex (PM)) in a group of 32 left hemisphere ...

  1. Hemispheric specialization in dogs for processing different acoustic stimuli.

    Directory of Open Access Journals (Sweden)

    Marcello Siniscalchi

    Full Text Available Considerable experimental evidence shows that functional cerebral asymmetries are widespread in animals. Activity of the right cerebral hemisphere has been associated with responses to novel stimuli and the expression of intense emotions, such as aggression, escape behaviour and fear. The left hemisphere uses learned patterns and responds to familiar stimuli. Although such lateralization has been studied mainly for visual responses, there is evidence in primates that auditory perception is lateralized and that vocal communication depends on differential processing by the hemispheres. The aim of the present work was to investigate whether dogs use different hemispheres to process different acoustic stimuli by presenting them with playbacks of a thunderstorm and their species-typical vocalizations. The results revealed that dogs usually process their species-typical vocalizations using the left hemisphere and the thunderstorm sounds using the right hemisphere. Nevertheless, conspecific vocalizations are not always processed by the left hemisphere, since the right hemisphere is used for processing vocalizations when they elicit intense emotion, including fear. These findings suggest that the specialisation of the left hemisphere for intraspecific communication is more ancient that previously thought, and so is specialisation of the right hemisphere for intense emotions.

  2. Cortical swallowing processing in early subacute stroke

    Directory of Open Access Journals (Sweden)

    Fischer Maren

    2011-03-01

    Full Text Available Abstract Background Dysphagia is a major complication in hemispheric as well as brainstem stroke patients causing aspiration pneumonia and increased mortality. Little is known about the recovery from dysphagia after stroke. The aim of the present study was to determine the different patterns of cortical swallowing processing in patients with hemispheric and brainstem stroke with and without dysphagia in the early subacute phase. Methods We measured brain activity by mean of whole-head MEG in 37 patients with different stroke localisation 8.2 +/- 4.8 days after stroke to study changes in cortical activation during self-paced swallowing. An age matched group of healthy subjects served as controls. Data were analyzed by means of synthetic aperture magnetometry and group analyses were performed using a permutation test. Results Our results demonstrate strong bilateral reduction of cortical swallowing activation in dysphagic patients with hemispheric stroke. In hemispheric stroke without dysphagia, bilateral activation was found. In the small group of patients with brainstem stroke we observed a reduction of cortical activation and a right hemispheric lateralization. Conclusion Bulbar central pattern generators coordinate the pharyngeal swallowing phase. The observed right hemispheric lateralization in brainstem stroke can therefore be interpreted as acute cortical compensation of subcortically caused dysphagia. The reduction of activation in brainstem stroke patients and dysphagic patients with cortical stroke could be explained in terms of diaschisis.

  3. Different patterns of language activation in post-stroke aphasia are detected by overt and covert versions of the verb generation fMRI task.

    Science.gov (United States)

    Allendorfer, Jane B; Kissela, Brett M; Holland, Scott K; Szaflarski, Jerzy P

    2012-03-01

    Post-stroke language functions depend on the relative contributions of the dominant and non-dominant hemispheres. Thus, we aimed to identify the neural correlates of overt and covert verb generation in adult post-stroke aphasia. Sixteen aphasic LMCA stroke patients (SPs) and 32 healthy controls (HCs) underwent language testing followed by fMRI while performing an overt event-related verb generation task (ER-VGT) isolating activations related to noun-verb semantic processing or to articulation and auditory processing, and a covert block design verb generation task (BD-VGT). BD-VGT activation patterns were consistent with previous studies, while ER-VGT showed different patterns in SPs relative to HCs including less left-hemispheric involvement during semantic processing and predominantly right-sided activation related to articulation and auditory processing. ER-VGT intra-scanner performance was positively associated with activation during semantic associations in the left middle temporal gyrus for HCs (p=0.031) and left middle frontal gyrus for SPs (p=0.042). Increased activation in superior frontal/cingulate gyri was associated with better intra-scanner performance (p=0.020). Lesion size negatively impacted verbal fluency tested with Controlled Oral Word Association Test (p=0.0092) and the Semantic Fluency Test (p=0.033) and trended towards a negative association with verb generation performance on the event-related verb generation task (p=0.081). Greater retention of pre-stroke language skills is associated with greater involvement of the left hemisphere with different cortical recruitment patterns observed in SPs versus HCs. Post-stroke verbal fluency may depend more upon the structural and functional integrity of the dominant left hemisphere language network rather than the shift to contralateral homologues.

  4. Carotid Artery Stenting Successfully Prevents Progressive Stroke Due to Mobile Plaque

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    Masahiro Oomura

    2015-05-01

    Full Text Available We report a case of progressive ischemic stroke due to a mobile plaque, in which carotid artery stenting successfully prevented further infarctions. A 78-year-old man developed acute multiple infarcts in the right hemisphere, and a duplex ultrasound showed a mobile plaque involving the bifurcation of the left common carotid artery. Maximal medical therapy failed to prevent further infarcts, and the number of infarcts increased with his neurological deterioration. Our present case suggests that the deployment of a closed-cell stent is effective to prevent the progression of the ischemic stroke due to the mobile plaque.

  5. Communication in conversation in stroke patients.

    Science.gov (United States)

    Rousseaux, Marc; Daveluy, Walter; Kozlowski, Odile

    2010-07-01

    In stroke patients, it has been suggested that communication disorders could result from lexical and syntactic disorders in left hemisphere lesions and from pragmatics problems in right lesions. However, we have little information on patient behaviour in dyadic communication, especially in conversation. Here, we analyzed the various processes participating in communication difficulties at the rehabilitation phase (1-6 months) post-stroke, in order to define the main mechanisms of verbal and non-verbal communication (VC, NVC) disorders and their relationship with aphasic disorders. Sixty-three patients were recruited, who belonged to six groups, with left or right cortico-sub-cortical (L-CSC, R-CSC) or sub-cortical (L-SC, R-SC), frontal (Fro) or posterior fossa (PF) lesions. They were compared with an equivalent control group (gender, age, education level). We used the Lille Communication Test, which comprises three parts: participation to communication (greeting, attention, engagement), verbal communication (verbal comprehension, speech outflow, intelligibility, word production, syntax, verbal pragmatics and verbal feedback) and non-verbal communication (understanding gestures, affective expressivity, producing gestures, pragmatics and feedback). We also used the Functional Communication Profile and the Boston Diagnostic Aphasia Examination (BDAE). Decrease in participation was found in L-CSC, R-CSC and Fro patients. Verbal communication was essentially disrupted in L-SCS and L-SC groups, including by verbal pragmatic disorders, and to a lesser degree in frontal patients. Nonverbal communication was mainly affected in R-CSC patients, especially by pragmatic difficulties. L-CSC patients showed an increase in gesture production, compensating for aphasia. In conclusion, communication disorders were relatively complex and could not be summarised by syntactical and lexical difficulties in left stroke and pragmatic problems in right stroke. The former also showed severe

  6. Successful Left Atrial Appendage Occlusion with the New Generation Amulet® Device after Late-Occurring Embolization of an Amplatzer® Cardiac Plug in a Patient with Repetitive Strokes

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    Marco R. Schroeter

    2016-01-01

    Full Text Available The Amplatzer Cardiac Plug (ACP is one of the most commonly used devices for percutaneous left atrial appendage (LAA closure in order to prevent a stroke in patients with atrial fibrillation and contraindication for long-term oral anticoagulation therapy. We have previously described a patient who had experienced an embolization of the ACP device about 12 months after implantation and the device could be percutaneously retrieved. A few years later, he suffered from a posterior stroke and a stroke located in the brainstem as well as a transischemic attack (TIA. In order to protect him from further cardioembolic events a reocclusion of the LAA with the new generation of ACP device, the Amplatzer Amulet, was performed. A stable position of the device within follow-up period could be confirmed and the patient was free of additional strokes/TIA or bleeding events. This case stresses the importance of proper LAA sizing in order to prevent device embolization and notes that LAA size is not static. Moreover, it demonstrates that repeated implantation of an LAA occlusion device was still possible; one should be aware of undersizing the LAA dimensions and that the modifications of new generation LAA occlusion devices may overcome limitations of first-generation devices in order to prevent a cardioembolic stroke.

  7. Global suppression of electrocortical activity in unilateral perinatal thalamic stroke.

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    Kharoshankaya, Liudmila

    2014-07-01

    We present an unusual case of persistent generalized electroencephalography (EEG) suppression and right-sided clonic seizures in a male infant born at 40(+2) weeks\\' gestation, birthweight 3240g, with an isolated unilateral thalamic stroke. The EEG at 13 hours after birth showed a generalized very low amplitude background pattern, which progressed to frequent electrographic seizures over the left hemisphere. The interictal background EEG pattern remained grossly abnormal over the next 48 hours, showing very low background amplitudes (<10μV). Magnetic resonance imaging revealed an isolated acute left-sided thalamic infarction. This is the first description of severe global EEG suppression caused by an isolated unilateral thalamic stroke and supports the role of the thalamus as the control centre for cortical electrical activity.

  8. A functional electric orthesis on the paretic leg improves quality of life of stroke patients.

    Science.gov (United States)

    Fernandes, Mara Renata; Carvalho, Luciane B C; Prado, Gilmar F

    2006-03-01

    Hemiparesia changes quality of life of patients with stroke making difficult a normal life. To evaluate the effect of Functional Eletric Orthesis (FEO) applied over the paretic leg in the quality of life of stroke patients. The quality of life of 50 stroke patients of Associacao de Assistencia a Crianca Deficiente (AACD) was evaluated with SF-36 questionnaire before and after the treatment with a FEO for rehabilitation of walking. We analyzed data according to gender and affected hemisphere. The average values from all domains of SF-36 improved significantly (pSocial Functioning. Patients with right hemiparesia improved more than those with left hemiparesia (p=0.02). FEO over a paretic leg is efficient to improve quality of life of stroke patients, mainly Physical Functioning.

  9. Morphological risk factors of stroke during thoracic endovascular aortic repair.

    Science.gov (United States)

    Kotelis, Drosos; Bischoff, Moritz S; Jobst, Bertram; von Tengg-Kobligk, Hendrik; Hinz, Ulf; Geisbüsch, Philipp; Böckler, Dittmar

    2012-12-01

    This study aims to identify independent factors correlating to an increased risk of perioperative stroke during thoracic endovascular aortic repair (TEVAR). A prospective maintained TEVAR database, medical records, and imaging studies of 300 patients (205 men; median age of all, 66 years, range 21-89), who underwent TEVAR between March 1997 and February 2011, were reviewed. Preoperative CT data sets were reviewed by two experienced radiologists with focus on the atheroma burden in the aortic arch (grade I, normal, to grade V, ulcerated or pedunculated atheroma). Aortic arch geometry (arch types I-III) was documented. Further parameters included in the univariate analysis were age, gender, urgency of repair, duration of procedure, adenosine-induced cardiac arrest or rapid pacing, proximal landing zone, left subclavian artery (LSA) coverage, and number of stent grafts. Multivariate logistic regression analysis was performed to assess the independent correlations of potential risk factors. Atherosclerotic aneurysm was the most common pathology (44%). One hundred and fifty-four of our patients (51%) were treated under urgent or emergent conditions. Seventeen percent of all patients had significant arch atheroma (grade IV or V), and 43% had a steep type III aortic arch. The perioperative stroke was 4% (12 patients; median age, 73 years, range 31-78). Two strokes were lethal (0.7%). All strokes were classified as embolic based on imaging characteristics. In eight patients, strokes were located in the left cerebral hemisphere (seven of them in the anterior and one in the posterior circulation). Four stroke patients (one in the left posterior circulation) underwent LSA coverage without revascularization. Three stroke patients had severe arch atheroma grade V. Five patients suffering stroke were recognized to have a type III aortic arch. Strokes were equally distributed between zones 0-2 vs. 3-4 (n = 6 each, 5 vs. 3.3%). The highest incidence was found in zone 1 (11

  10. Hemispheric processing of memory is affected by sleep.

    Science.gov (United States)

    Monaghan, Padraic; Shaw, John J; Ashworth-Lord, Anneliese; Newbury, Chloe R

    2017-04-01

    Sleep is known to affect learning and memory, but the extent to which it influences behavioural processing in the left and right hemispheres of the brain is as yet unknown. We tested two hypotheses about lateralised effects of sleep on recognition memory for words: whether sleep reactivated recent experiences of words promoting access to the long-term store in the left hemisphere (LH), and whether sleep enhanced spreading activation differentially in semantic networks in the hemispheres. In Experiment 1, participants viewed lists of semantically related words, then slept or stayed awake for 12h before being tested on seen, unseen but related, or unrelated words presented to the left or the right hemisphere. Sleep was found to promote word recognition in the LH, and to spread activation equally within semantic networks in both hemispheres. Experiment 2 ensured that the results were not due to time of day effects influencing cognitive performance. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Effect of specialized task training of each hemisphere on interlimb transfer in individuals with hemiparesis.

    Science.gov (United States)

    Yoo, In-gyu; Jung, Min-ye; Yoo, Eun-young; Park, Soo-hyun; Park, Ji-hyuk; Lee, Jin; Kim, Han-sol

    2013-01-01

    Therapeutic concept of interlimb transfer provides very important information relevant to patients with stroke because it can be applied to help these patients recover movement skills disrupted following unilateral damage to the brain. The purpose of this study was to determine the transfer effects for both specialized training in each hemisphere and reversed training of a specialized task. Twenty patients (ten women and ten men) with stroke and hemiparesis participated. All participants were in Brunnstrom recovery stage five or higher for arm and hand function and had Mini-Mental State Examination scores ≥25. We used a training task involving a modified static cone, modified box and block, and modified pegboard tasks. The specified-training group performed the reaching movements (based on grip, reach, and release movements) in a modified training setting in which left-handed participants began from a single starting location and proceeded to one of three target locations (1S3T condition), and the right-handed participants started form one of three starting locations and proceeded to a single target location (3S1T condition). The unspecified training group performed these movements starting under reverse-start and target conditions. As a result of the left-to-right limb transfer in the specified-training group differed significantly in duration from that in the pre-training group. Also, the biceps brachii and triceps (lateral head) muscles were significantly more active after performing the specified training than before. On the other hand, the activity of the upper trapezius muscle did not significantly differ after specified training compared with before training. Consequently, a symmetric transfer advantage was observed that depended on the characteristic resources of each hemisphere. The transfer of specified training from one arm to the other had a more positive influence on functional recovery than did unspecified training for patients with stroke and

  12. VERBAL CHOICE IN ISCHEMIC STROKE PATIENTS WITH ANOMIC APHASIA.

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    Мaya P. Danovska

    2014-03-01

    Full Text Available Background and purposes: Anomic aphasia is common in patients with left hemispheric strokes. The purpose of this study was to explore the verbal production of ischemic stroke patients with anomic aphasia. Contingent and methods: Fifty ischemic stroke patients admitted to the Neurology Clinic of University Hospital Pleven were studied by neuropsychological battery and CT scan of the brain. Verbal productivity changes found were analyzed in relation to the speech recovery education. Results: All the patients showed lower scores at all nominative and reproductive speech subtests. Discussion: Among the ischemic stroke patients with mild anomic aphasia comparatively great was the percentage of low frequency word actualization and verbal fluency impairment. The usage of nominatives in speech expression of ischemic stroke patients is less as compared with that one of predicatives. Actualization of particles, unions, prepositions and interjections was comparatively high thus compensating the difficulty in choice of a definite lexical number. Conclusion: Future studies on testing of verbal choice in ischemic stroke patients should confirm its practical significance for the assessment of speech disorders concerning a special speech- recovery education.

  13. Inpatient rehabilitation outcomes of patients with apraxia after stroke.

    Science.gov (United States)

    Wu, Andy J; Burgard, Emily; Radel, Jeff

    2014-01-01

    Stroke-induced paresis commands much attention during rehabilitation; other stroke-related consequences receive less consideration. Apraxia is a stroke disorder that may have important implications for rehabilitation and recovery. To investigate association of apraxia with stroke rehabilitation outcomes during inpatient rehabilitation. This cohort study compared patients with and without apraxia after a first left hemispheric stroke. All study patients received standard of care. Clinical measures were the Functional Independence Measure (FIM) and the upper extremity section of the Fugl-Meyer Assessment (FMA) administered upon admission and at discharge. Length of stay was also documented. Florida Apraxia Battery subtests were used to classify patients with apraxia. Fifteen patients were included in this study, 10 of whom had apraxia. Data analysis revealed that patients with apraxia exhibited improvement from admission to discharge in clinical measures; however, admission FIM score was significantly lower compared to patients without apraxia. There was no statistically significant difference between groups on FMA score, length of stay, or amount of change on clinical measures. This study of acute patients found those with apraxia to be significantly less independent upon admission to inpatient rehabilitation compared to patients without apraxia. Although both groups improved a similar amount during rehabilitation, patients with apraxia discharged at a level of independence comparable to patients without apraxia upon admission. Such disparity in independence is of concern, and apraxia as a factor in stroke rehabilitation and recovery deserves further attention.

  14. Game Utilization as a Media to Train the Balance of Left and Right Brain

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    Evan Wijaya

    2017-10-01

    Full Text Available Human have two brain hemispheres, left hemisphere and right hemisphere. Left hemisphere is used for processing language, words, numbers, equations, etc. Right hemisphere is used for processing creativity, imagination, music, color, etc. Every human should have balance between left and right hemisphere. One method that could be used for balancing brain hemispheres is to use left and right hands for using tools, writing, or typing. “Typing Rhythm” is a game for PC platform, the purpose of this game is for brain balancing exercise by typing lyric of a song while the song is played.

  15. Effect of patent ductus arteriosus and patent foramen ovale on left ventricular stroke volume measurement by electrical velocimetry in comparison to transthoracic echocardiography in neonates.

    Science.gov (United States)

    Blohm, Martin Ernst; Hartwich, Jana; Obrecht, Denise; Kersten, Jan Felix; Singer, Dominique

    2017-06-01

    This prospective single-center observational study compared impedance cardiography [electrical velocimetry (EV)] with transthoracic echocardiography (TTE, based on trans-aortic flow) and analyzed the influence of physiological shunts, such as patent ductus arteriosus (PDA) or patent foramen ovale (PFO), on measurement accuracy. Two hundred and ninety-one triplicate simultaneous paired left ventricular stroke volume (LVSV) measurements by EV (LVSV EV ) and TTE (LVSV TTE ) in 99 spontaneously breathing neonates (mean weight 3270 g; range 1227-4600 g) were included. For the whole cohort, the mean absolute LVSV EV was 5.5 mL, mean LVSV TTE was 4.9 mL, resulting in an absolute Bland-Altman bias of -0.7 mL (limits of agreement LOA -3.0 to 1.7 mL), relative bias -12.8 %; mean percentage error MPE 44.9 %; true precision TP EV 33.4 % (n = 99 aggregated data points). In neonates without shunts (n = 32): mean LVSV EV 5.0 mL, mean LVSV TTE 4.6 mL, Bland-Altman bias -0.4 mL (LOA -2.8 to 2.0 mL), relative bias -8.2 %; MPE 50.7 %; TP EV 40.9 %. In neonates with shunts (PDA and/or PFO; n = 67): mean LVSV EV 5.8 mL, mean LVSV TTE 5.0 mL, bias -0.8 mL (LOA -3.1 to 1.5 mL), relative bias -14.8 %, MPE 41.9 %, TP EV 29.3 %. Accuracy was affected by PDA and/or PFO, with a significant increase in the relative difference in LVSV EV versus LVSV TTE : Subjects without shunts -2.9 % (n = 91), PFO alone -9.6 % (n = 125), PDA alone -14.0 % (n = 12), and PDA and PFO -18.5 % (n = 63). Physiological shunts (PDA and/or PFO) in neonates affect measurement accuracy and cause overestimation of LVSV EV compared with LVSV TTE .

  16. Bow hunter's stroke associated with atlantooccipital assimilation--case report.

    Science.gov (United States)

    Sakai, K; Tsutsui, T

    1999-09-01

    A 39-year-old male presented with bow hunter's stroke manifesting as repeated vertebrobasilar ischemic attacks induced by head rotation 45 degrees to the left. Three-dimensional computed tomography angiography clearly showed the occluded right vertebral artery (VA) between the axis and atlas. Single photon emission computed tomography study showed diffuse hypoperfusion of the brain stem and bilateral cerebellar hemispheres, suggesting hemodynamic compromise of these regions. He refused surgery and was treated conservatively. The most likely mechanism is that the affected VA was fixed by the ossification of the atlantooccipital membrane, vascular groove, and transverse foramen of the atlas, and therefore became elongated and compressed by head-turning.

  17. Cardiac asystole associated with seizures of right hemispheric onset

    Directory of Open Access Journals (Sweden)

    Jennifer Chu

    2014-01-01

    Full Text Available Ictal asystole is frequently underrecognized despite being a potentially lethal condition. We report two cases of ictal asystole with right hemispheric onset. These cases are unique since previous literature reports that seizures associated with bradyarrhythmias typically arise from left hemispheric foci. These cases further underscore the importance of clinical vigilance and the need of an enhanced diagnostic biomarker.

  18. Language-specific dysgraphia in Korean stroke patients.

    Science.gov (United States)

    Yoon, Ji Hye; Suh, Mee Kyung; Kim, HyangHee

    2010-12-01

    We investigated how changes in the writing of 14 Korean stroke patients reflect the unique features of the Korean writing system. The Korean writing system, Han-geul, has both linguistic and visuospatial/constructive characteristics. In the visuospatial construction of a syllable, the component consonant(s) and vowel(s) must be arranged from top-to-bottom and/or left-to-right within the form of a square. This syllabic organization, unique to Korean writing, may distinguish dysgraphia in Korean patients from the disorder in other languages, and reveal the effects of stroke on visuospatial/constructive abilities. We compared 2 groups of patients affected by stroke, 1 group with left hemisphere (LH) lesions and the other with right hemisphere (RH) lesions. We instructed them to write from a dictation of 90 monosyllabic stimuli, each presented with a real word cue. Patients had to repeat a target syllable and a word cue, and then to write the target syllable only. Patients with LH and RH lesions produced qualitatively different error patterns. While the LH lesion group produced primarily linguistic errors, visuospatial/constructive errors predominated in the group with RH lesions. With regard to language-specific features, these Korean patients with RH lesions produced diverse visuospatial/constructive errors not commonly observed in dysgraphia of the English language. Language-specific writing errors by Korean stroke patients reflect the unique characteristics of Korean writing, which include the arrangement of strokes and graphemes within a square syllabic form by dimensional and spatial rules. These findings support the notion that the Korean writing system possesses a language-specific nature with both linguistic and visuospatial/constructive processes. Distinctive patterns of dysgraphia in the Korean language also suggest interactivity between linguistic and visuospatial/constructive levels of processing. This study is noteworthy for its systematic description of

  19. Frontal lobe ischemic stroke presenting with peripheral type facial palsy: A crucial diagnostic challenge in emergency practice

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    Halil Onder

    2017-09-01

    Full Text Available Here, we illustrate a 69-year old female admitting with weakness on left side of the face who firstly considered peripheral facial palsy in the forefront. However, detailed neurological examination and cranial MRI findings finally yielded the proper diagnosis of right hemisphere ischemic stroke. Via this remarkable presentation, we point out the clinical challenges in evaluation processes of patients with facial palsy in emergency practice and emphasize the importance of detailed examination for the proper diagnosis as well as initiation of appropriate treatment agents without delay. Keywords: Facial paralysis, Stroke, Emergency department, Facial innervation, Pathophysiology

  20. Dysarthria in stroke: a narrative review of its description and the outcome of intervention.

    Science.gov (United States)

    Mackenzie, Catherine

    2011-04-01

    Dysarthria is a frequent and persisting sequel to stroke and arises from varied lesion locations. Although the presence of dysarthria is well documented, for stroke there are scant data on presentation and intervention outcome. A literature search was undertaken to evaluate (a) the features of dysarthria in adult stroke populations relative to the conventional Mayo system for classification, which was developed from diverse pathological groups, and (b) the current status of evidence for the effectiveness of intervention in dysarthria caused by stroke. A narrative review of results is presented. The limited data available indicate that, regardless of stroke location, imprecise articulation and slow speaking rate are consistent features, and voice disturbances, especially harshness, and reduced prosodic variation are also common. Dysarthria is more prevalent in left than in right hemisphere lesions. There is a need for comprehensive, thorough analysis of dysarthria features, involving larger populations, with stroke and other variables controlled and with appropriate age-referenced control data. There is low level evidence for benefits arising from intervention in stroke-related dysarthria. Because studies involve few participants, without external control, and sometimes include stroke with other aetiologies, their results lack the required weight for confident evidence-based practice.

  1. Association of ideomotor apraxia with lesion site, etiology, neglect, and functional independence in patients with first ever stroke.

    Science.gov (United States)

    Civelek, Gul Mete; Atalay, Ayce; Turhan, Nur

    2015-04-01

    Ideomotor apraxia (IMA) is characterized by the inability to correctly imitate hand gestures and voluntarily pantomime tool use. The relationship between IMA and characteristics of stroke has not been totally elucidated. This study aimed to find out associations between presence of IMA and stroke etiology, site of the lesions, neglect, and temporal and functional parameters of stroke in patients with first ever stroke. Thirty-nine patients with first ever stroke were included. Patients with severe cognitive deficits were excluded. Assessment tools included Ideomotor Apraxia Test, Functional Independence Measure (FIM), Brunnstrom recovery stages, Mini Mental Test (MMT), and star cancellation test. Etiology (hemorrhagic or ischemic) and site of stroke was assessed through brain imaging methods. Location and size of ischemic lesion was determined by using the Oxfordshire Community Stroke Project system. IMA was identified in 35.9% of the patients. Patients with IMA had significantly lower FIM scores both on admission and discharge (P = 0.001, P = 0.001). Presence of IMA was significantly associated with the presence of neglect (P = 0.004), total anterior circulation ischemia (TACI) (P stroke etiology had no impact on the presence of IMA. IMA was in concordance with poor cognitive and functional state and was not limited to left hemisphere lesions. The study revealed strong associations between IMA, neglect, and TACI. Every patient with stroke should be evaluated for the presence of IMA on admission to rehabilitation unit.

  2. Mapping causal functional contributions derived from the clinical assessment of brain damage after stroke.

    Science.gov (United States)

    Zavaglia, Melissa; Forkert, Nils D; Cheng, Bastian; Gerloff, Christian; Thomalla, Götz; Hilgetag, Claus C

    2015-01-01

    Lesion analysis reveals causal contributions of brain regions to mental functions, aiding the understanding of normal brain function as well as rehabilitation of brain-damaged patients. We applied a novel lesion inference technique based on game theory, Multi-perturbation Shapley value Analysis (MSA), to a large clinical lesion dataset. We used MSA to analyze the lesion patterns of 148 acute stroke patients together with their neurological deficits, as assessed by the National Institutes of Health Stroke Scale (NIHSS). The results revealed regional functional contributions to essential behavioral and cognitive functions as reflected in the NIHSS, particularly by subcortical structures. There were also side specific differences of functional contributions between the right and left hemispheric brain regions which may reflect the dominance of the left hemispheric syndrome aphasia in the NIHSS. Comparison of MSA to established lesion inference methods demonstrated the feasibility of the approach for analyzing clinical data and indicated its capability for objectively inferring functional contributions from multiple injured, potentially interacting sites, at the cost of having to predict the outcome of unknown lesion configurations. The analysis of regional functional contributions to neurological symptoms measured by the NIHSS contributes to the interpretation of this widely used standardized stroke scale in clinical practice as well as clinical trials and provides a first approximation of a 'map of stroke'.

  3. A vision of graded hemispheric specialization.

    Science.gov (United States)

    Behrmann, Marlene; Plaut, David C

    2015-11-01

    Understanding the process by which the cerebral hemispheres reach their mature functional organization remains challenging. We propose a theoretical account in which, in the domain of vision, faces and words come to be represented adjacent to retinotopic cortex by virtue of the need to discriminate among homogeneous exemplars. Orthographic representations are further constrained to be proximal to typically left-lateralized language-related information to minimize connectivity length between visual and language areas. As reading is acquired, orthography comes to rely more heavily (albeit not exclusively) on the left fusiform region to bridge vision and language. Consequently, due to competition from emerging word representations, face representations that were initially bilateral become lateralized to the right fusiform region (albeit, again, not exclusively). We review recent research that describes constraints that give rise to this graded hemispheric arrangement. We then summarize empirical evidence from a variety of studies (behavioral, evoked response potential, functional imaging) across different populations (children, adolescents, and adults; left handers and individuals with developmental dyslexia) that supports the claims that hemispheric lateralization is graded rather than binary and that this graded organization emerges dynamically over the course of development. Perturbations of this system either during development or in adulthood provide further insights into the principles governing hemispheric organization. © 2015 New York Academy of Sciences.

  4. How to engage the right brain hemisphere in aphasics without even singing: evidence for two paths of speech recovery.

    Science.gov (United States)

    Stahl, Benjamin; Henseler, Ilona; Turner, Robert; Geyer, Stefan; Kotz, Sonja A

    2013-01-01

    There is an ongoing debate as to whether singing helps left-hemispheric stroke patients recover from non-fluent aphasia through stimulation of the right hemisphere. According to recent work, it may not be singing itself that aids speech production in non-fluent aphasic patients, but rhythm and lyric type. However, the long-term effects of melody and rhythm on speech recovery are largely unknown. In the current experiment, we tested 15 patients with chronic non-fluent aphasia who underwent either singing therapy, rhythmic therapy, or standard speech therapy. The experiment controlled for phonatory quality, vocal frequency variability, pitch accuracy, syllable duration, phonetic complexity and other influences, such as the acoustic setting and learning effects induced by the testing itself. The results provide the first evidence that singing and rhythmic speech may be similarly effective in the treatment of non-fluent aphasia. This finding may challenge the view that singing causes a transfer of language function from the left to the right hemisphere. Instead, both singing and rhythmic therapy patients made good progress in the production of common, formulaic phrases-known to be supported by right corticostriatal brain areas. This progress occurred at an early stage of both therapies and was stable over time. Conversely, patients receiving standard therapy made less progress in the production of formulaic phrases. They did, however, improve their production of non-formulaic speech, in contrast to singing and rhythmic therapy patients, who did not. In light of these results, it may be worth considering the combined use of standard therapy and the training of formulaic phrases, whether sung or rhythmically spoken. Standard therapy may engage, in particular, left perilesional brain regions, while training of formulaic phrases may open new ways of tapping into right-hemisphere language resources-even without singing.

  5. How to engage the right brain hemisphere in aphasics without even singing: evidence for two paths of speech recovery

    Directory of Open Access Journals (Sweden)

    Benjamin eStahl

    2013-02-01

    Full Text Available There is an ongoing debate as to whether singing helps left-hemispheric stroke patients recover from non-fluent aphasia through stimulation of the right hemisphere. According to recent work, it may not be singing itself that aids speech production in non-fluent aphasic patients, but rhythm and lyric type. However, the long-term effects of melody and rhythm on speech recovery are largely unknown. In the current experiment, we tested 15 patients with chronic non-fluent aphasia who underwent either singing therapy, rhythmic therapy, or standard speech therapy. The experiment controlled for phonatory quality, vocal frequency variability, pitch accuracy, syllable duration, phonetic complexity and other influences, such as the acoustic setting and learning effects induced by the testing itself. The results provide the first evidence that singing and rhythmic speech may be similarly effective in the treatment of non-fluent aphasia. This finding may challenge the view that singing causes a transfer of language function from the left to the right hemisphere. Instead, both singing and rhythmic therapy patients made good progress in the production of common, formulaic phrases—known to be supported by right corticostriatal brain areas. This progress occurred at an early stage of both therapies and was stable over time. Conversely, patients receiving standard therapy made less progress in the production of formulaic phrases. They did, however, improve their production of non-formulaic speech, in contrast to singing and rhythmic therapy patients, who did not. In light of these results, it may be worth considering the combined use of standard therapy and the training of formulaic phrases, whether sung or rhythmically spoken. Standard therapy may engage, in particular, left perilesional brain regions, while training of formulaic phrases may open new ways of tapping into right-hemisphere language resources—even without singing.

  6. How do our brain hemispheres cooperate to avoid false memories?

    Science.gov (United States)

    Bergert, Susanne

    2013-02-01

    Memories are not always as reliable as they may appear. The occurrence of false memories can be reduced, however, by enhancing the cooperation between the two brain hemispheres. Yet is the communication from left to right hemisphere as helpful as the information transfer from right to left? To address this question, 72 participants were asked to learn 16 word lists. Applying the Deese-Roediger-McDermott paradigm, the words in each list were associated with an unpresented prototype word. In the test condition, learned words and corresponding prototypes were presented along with non-associated new words, and participants were asked to indicate which of the words they recognized. Crucially, both study and test words were projected to only one hemisphere in order to stimulate each hemisphere separately. It was found that false recognitions occurred significantly less often when the right hemisphere studied and the left hemisphere recognized the stimuli. Moreover, only the right-to-left direction of interhemispheric communication reduced false memories significantly, whereas left-to-right exchange did not. Further analyses revealed that the observed reduction of false memories was not due to an enhanced discrimination sensitivity, but to a stricter response bias. Hence, the data suggest that interhemispheric cooperation does not improve the ability to tell old and new apart, but rather evokes a conservative response tendency. Future studies may narrow down in which cognitive processing steps interhemispheric interaction can change the response criterion. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Word and face recognition deficits following posterior cerebral artery stroke

    DEFF Research Database (Denmark)

    Kuhn, Christina D.; Asperud Thomsen, Johanne; Delfi, Tzvetelina

    2016-01-01

    Abstract Recent findings have challenged the existence of category specific brain areas for perceptual processing of words and faces, suggesting the existence of a common network supporting the recognition of both. We examined the performance of patients with focal lesions in posterior cortical...... areas to investigate whether deficits in recognition of words and faces systematically co-occur as would be expected if both functions rely on a common cerebral network. Seven right-handed patients with unilateral brain damage following stroke in areas supplied by the posterior cerebral artery were...... included (four with right hemisphere damage, three with left, tested at least 1 year post stroke). We examined word and face recognition using a delayed match-to-sample paradigm using four different categories of stimuli: cropped faces, full faces, words, and cars. Reading speed and word length effects...

  8. Post-stroke pure apraxia of speech - A rare experience.

    Science.gov (United States)

    Polanowska, Katarzyna Ewa; Pietrzyk-Krawczyk, Iwona

    Apraxia of speech (AOS) is a motor speech disorder, most typically caused by stroke, which in its "pure" form (without other speech-language deficits) is very rare in clinical practice. Because some observable characteristics of AOS overlap with more common verbal communication neurologic syndromes (i.e. aphasia, dysarthria) distinguishing them may be difficult. The present study describes AOS in a 49-year-old right-handed male after left-hemispheric stroke. Analysis of his articulatory and prosodic abnormalities in the context of intact communicative abilities as well as description of symptoms dynamics over time provides valuable information for clinical diagnosis of this specific disorder and prognosis for its recovery. This in turn is the basis for the selection of appropriate rehabilitative interventions. Copyright © 2016 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  9. Impairment on theory of mind and empathy in patients with stroke.

    Science.gov (United States)

    Yeh, Zai-Ting; Tsai, Chung-Fen

    2014-08-01

    Impaired social function has been described in patients following stroke. The present study was designed to explore the degree of impairment in the ability to infer mental states in others, or cognitive and affective theory of mind, and empathy, in patients with stroke. A total of 34 patients with stroke were compared to 40 control subjects on tasks testing verbal and non-verbal theory of mind and empathy. Results indicated that patients with stroke were significantly impaired in both cognitive and affective theory of mind, even controlling for basic cognitive function and emotional processing. The patients with right stroke had poorer performance than those with left stroke on the cognitive component of non-verbal theory of mind. On the subscale of cognitive empathy, the right stroke group had poorer performance on perspective-taking than the control group. The right hemisphere may play an important role in decoding non-verbal cues to infer others' minds as well as the processing of empathy, especially the ability of perspective-taking. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  10. Hemispheric asymmetries: The comparative view

    Directory of Open Access Journals (Sweden)

    Sebastian eOcklenburg

    2012-01-01

    Full Text Available Hemispheric asymmetries play an important role in almost all cognitive functions. For more than a century, they were considered to be uniquely human but now an increasing number of findings in all vertebrate classes make it likely that we inherited our asymmetries from common ancestors. Thus, studying animal models could provide unique insights into the mechanisms of lateralization. We outline three such avenues of research by providing an overview of experiments on left-right differences in the connectivity of sensory systems, the embryonic determinants of brain asymmetries, and the genetics of lateralization. All these lines of studies could provide a wealth of insights into our own asymmetries that should and will be exploited by future analyses.

  11. Hemispheric dominance and cell phone use.

    Science.gov (United States)

    Seidman, Michael D; Siegel, Bianca; Shah, Priyanka; Bowyer, Susan M

    2013-05-01

    A thorough understanding of why we hold a cell phone to a particular ear may be of importance when studying the impact of cell phone safety. To determine if there is an obvious association between sidedness of cell phone use and auditory hemispheric dominance (AHD) or language hemispheric dominance (LHD). It is known that 70% to 95% of the population are right-handed, and of these, 96% have left-brain LHD. We have observed that most people use their cell phones in their right ear. An Internet survey was e-mailed to individuals through surveymonkey.com. The survey used a modified Edinburgh Handedness Inventory protocol. Sample questions surveyed which hand was used to write with, whether the right or left ear was used for phone conversations, as well as whether a brain tumor was present. General community. An Internet survey was randomly e-mailed to 5000 individuals selected from an otology online group, patients undergoing Wada testing and functional magnetic resonance imaging, as well as persons on the university listserv, of which 717 surveys were completed. Determination of hemispheric dominance based on preferred ear for cell phone use. A total of 717 surveys were returned. Ninety percent of the respondents were right handed, and 9% were left handed. Sixty-eight percent of the right-handed people used the cell phone in their right ear, 25% in the left ear, and 7% had no preference. Seventy-two of the left-handed respondents used their left ear, 23% used their right ear, and 5% had no preference. Cell phone use averaged 540 minutes per month over the past 9 years. An association exists between hand dominance laterality of cell phone use (73%) and our ability to predict hemispheric dominance. Most right-handed people have left-brain LHD and use their cell phone in their right ear. Similarly, most left-handed people use their cell phone in their left ear. Our study suggests that AHD may differ from LHD owing to the difference in handedness and cell phone ear use

  12. Stroke Treatments

    Science.gov (United States)

    ... Month Infographic Stroke Hero F.A.S.T. Quiz Stroke Treatment Stroke used to rank fourth in leading causes of ... type of treatment depends on the type of stroke. Ischemic stroke happens when a clot blocks a ...

  13. The left superior temporal gyrus is a shared substrate for auditory short-term memory and speech comprehension: evidence from 210 patients with stroke

    OpenAIRE

    Leff, Alexander P.; Schofield, Thomas M.; Crinion, Jennifer T.; Seghier, Mohamed L.; Grogan, Alice; Green, David W.; Price, Cathy J.

    2009-01-01

    Competing theories of short-term memory function make specific predictions about the functional anatomy of auditory short-term memory and its role in language comprehension. We analysed high-resolution structural magnetic resonance images from 210 stroke patients and employed a novel voxel based analysis to test the relationship between auditory short-term memory and speech comprehension. Using digit span as an index of auditory short-term memory capacity we found that the structural integrit...

  14. Glutamate is down-regulated and tinnitus loudness-levels decreased following rTMS over auditory cortex of the left hemisphere: A prospective randomized single-blinded sham-controlled cross-over study.

    Science.gov (United States)

    Cacace, Anthony T; Hu, Jiani; Romero, Stephen; Xuan, Yang; Burkard, Robert F; Tyler, Richard S

    2017-11-14

    Using a prospective randomized single-blinded sham-controlled cross-over design, we studied the efficacy of low frequency (1-Hz) repetitive transcranial magnetic stimulation (rTMS) over auditory cortex of the left temporal lobe as an experimental treatment modality for noise-induced tinnitus. Pre/post outcome measures for sham vs. active rTMS conditions included differential changes in tinnitus loudness, self-perceived changes in the Tinnitus Handicap Questionnaire (THQ), and neurochemical changes of brain metabolite concentrations using single voxel proton magnetic resonance spectroscopy ( 1 H-MRS) obtained from left and right auditory cortical areas. While no subject in our sample had complete abatement of their tinnitus percept, active but not sham rTMS significantly reduced the loudness level of the tinnitus perception on the order of 4.5 dB; improved subscales in several content areas on the THQ, and down regulated (reduced) glutamate concentrations specific to the auditory cortex of the left temporal lobe that was stimulated. In addition, significant pair-wise correlations were observed among questionnaire variables, metabolite variables, questionnaire-metabolite variables, and metabolite-loudness variables. As part of this correlation analysis, we demonstrate for the first time that active rTMS produced a down regulation in the excitatory neurotransmitter glutamate that was highly correlated (r = 0.77, p < 0.05) with a reduction in tinnitus loudness levels measured psychoacoustically with a magnitude estimation procedure. Overall, this study provides unique information on neurochemical, psychoacoustic, and questionnaire-related profiles which emphasizes the emerging fields of perceptual and cognitive MRS and provides a perspective on a new frontier in auditory and tinnitus-related research. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Reading without the left ventral occipito-temporal cortex

    Science.gov (United States)

    Seghier, Mohamed L.; Neufeld, Nicholas H.; Zeidman, Peter; Leff, Alex P.; Mechelli, Andrea; Nagendran, Arjuna; Riddoch, Jane M.; Humphreys, Glyn W.; Price, Cathy J.

    2012-01-01

    The left ventral occipito-temporal cortex (LvOT) is thought to be essential for the rapid parallel letter processing that is required for skilled reading. Here we investigate whether rapid written word identification in skilled readers can be supported by neural pathways that do not involve LvOT. Hypotheses were derived from a stroke patient who acquired dyslexia following extensive LvOT damage. The patient followed a reading trajectory typical of that associated with pure alexia, re-gaining the ability to read aloud many words with declining performance as the length of words increased. Using functional MRI and dynamic causal modelling (DCM), we found that, when short (three to five letter) familiar words were read successfully, visual inputs to the patient’s occipital cortex were connected to left motor and premotor regions via activity in a central part of the left superior temporal sulcus (STS). The patient analysis therefore implied a left hemisphere “reading-without-LvOT” pathway that involved STS. We then investigated whether the same reading-without-LvOT pathway could be identified in 29 skilled readers and whether there was inter-subject variability in the degree to which skilled reading engaged LvOT. We found that functional connectivity in the reading-without-LvOT pathway was strongest in individuals who had the weakest functional connectivity in the LvOT pathway. This observation validates the findings of our patient’s case study. Our findings highlight the contribution of a left hemisphere reading pathway that is activated during the rapid identification of short familiar written words, particularly when LvOT is not involved. Preservation and use of this pathway may explain how patients are still able to read short words accurately when LvOT has been damaged. PMID:23017598

  16. Apraxia in left-handers.

    Science.gov (United States)

    Goldenberg, Georg

    2013-08-01

    In typical right-handed patients both apraxia and aphasia are caused by damage to the left hemisphere, which also controls the dominant right hand. In left-handed subjects the lateralities of language and of control of the dominant hand can dissociate. This permits disentangling the association of apraxia with aphasia from that with handedness. Pantomime of tool use, actual tool use and imitation of meaningless hand and finger postures were examined in 50 consecutive left-handed subjects with unilateral hemisphere lesions. There were three aphasic patients with pervasive apraxia caused by left-sided lesions. As the dominant hand is controlled by the right hemisphere, they constitute dissociations of apraxia from handedness. Conversely there were also three patients with pervasive apraxia caused by right brain lesions without aphasia. They constitute dissociations of apraxia from aphasia. Across the whole group of patients dissociations from handedness and from aphasia were observed for all manifestations of apraxia, but their frequency depended on the type of apraxia. Defective pantomime and defective tool use occurred rarely without aphasia, whereas defective imitation of hand, but not finger, postures was more frequent after right than left brain damage. The higher incidence of defective imitation of hand postures in right brain damage was mainly due to patients who had also hemi-neglect. This interaction alerts to the possibility that the association of right hemisphere damage with apraxia has to do with spatial aptitudes of the right hemisphere rather than with its control of the dominant left hand. Comparison with data from right-handed patients showed no differences between the severity of apraxia for imitation of hand or finger postures, but impairment on pantomime of tool use was milder in apraxic left-handers than in apraxic right-handers. This alleviation of the severity of apraxia corresponded with a similar alleviation of the severity of aphasia as

  17. Post-Stroke Depression, Apathy and Alexithymia

    Directory of Open Access Journals (Sweden)

    Oriana Horta Rendeiro Correia Pinto

    2015-06-01

    Full Text Available Introduction: Several behavioural changes can occur as a consequence of stroke. A large number of studies have evaluated the frequency and severity of post-stroke depression,  apathy  and  alexithymia  that  result from stroke, however the published data is contradictory.Aims: The aim of this article is to present a literature review of the concepts of depression, apathy  and  alexithymia  and  post-stroke neuroanatomical  findings  that  support these psychopathological observations.Methods: Literature review of selected articles and books deemed relevant by the authors, using Medline/Pubmed database with the combination of the following key-words: “stroke”, “apathy”, “alexithymia”, “depression”,  published  between  1973  and  2013. References of the selected articles and books were also considered.Results  and  Conclusions: After  stroke, many patients are left with variable levels of disability, resulting in a mourning process, and this emotional response is thought to be a normative one to post-stroke problems. It has been understood that the depressive dimension is associated with left frontal lobe functioning  (the  so-called  left  frontal  lobe theory, whereas the apathetic dimension is associated with the basal ganglia. The rate of apathy is lower in patients without previous cerebrovascular  disease;  the  rate  of ‘pure’ apathy (without concomitant depression is twice as frequent as the rate of ‘pure’ depression  (without  concomitant  apathy. Apathetic patients are more frequently and severely depressed and cognitively impaired in comparison to nonapathetic patients. The mechanisms  underlying reduced  emotional  consciousness  and  emotional  blunting following stroke of the MCA are still poorly understood. Apathy and adynamia can be attributed to lesions in the insula and basal ganglia, however reduced emotional awareness can occur as a consequence of changes in

  18. Neuroimaging of stroke recovery from aphasia - Insights into plasticity of the human language network.

    Science.gov (United States)

    Hartwigsen, Gesa; Saur, Dorothee

    2017-11-23

    The role of left and right hemisphere brain regions in language recovery after stroke-induced aphasia remains controversial. Here, we summarize how neuroimaging studies increase the current understanding of functional interactions, reorganization and plasticity in the language network. We first discuss the temporal dynamics across the time course of language recovery, with a main focus on longitudinal studies from the acute to the chronic phase after stroke. These studies show that the functional contribution of perilesional and spared left hemisphere as well as contralesional right hemisphere regions to language recovery changes over time. The second section introduces critical variables and recent advances on early prediction of subsequent outcome. In the third section, we outline how multi-method approaches that combine neuroimaging techniques with non-invasive brain stimulation elucidate mechanisms of plasticity and reorganization in the language network. These approaches provide novel insights into general mechanisms of plasticity in the language network and might ultimately support recovery processes during speech and language therapy. Finally, the neurobiological correlates of therapy-induced plasticity are discussed. We argue that future studies should integrate individualized approaches that might vary the combination of language therapy with specific non-invasive brain stimulation protocols across the time course of recovery. The way forward will include the combination of such approaches with large data sets obtained from multicentre studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Role of Acute Lesion Topography in Initial Ischemic Stroke Severity and Long-Term Functional Outcomes.

    Science.gov (United States)

    Wu, Ona; Cloonan, Lisa; Mocking, Steven J T; Bouts, Mark J R J; Copen, William A; Cougo-Pinto, Pedro T; Fitzpatrick, Kaitlin; Kanakis, Allison; Schaefer, Pamela W; Rosand, Jonathan; Furie, Karen L; Rost, Natalia S

    2015-09-01

    Acute infarct volume, often proposed as a biomarker for evaluating novel interventions for acute ischemic stroke, correlates only moderately with traditional clinical end points, such as the modified Rankin Scale. We hypothesized that the topography of acute stroke lesions on diffusion-weighted magnetic resonance imaging may provide further information with regard to presenting stroke severity and long-term functional outcomes. Data from a prospective stroke repository were limited to acute ischemic stroke subjects with magnetic resonance imaging completed within 48 hours from last known well, admission NIH Stroke Scale (NIHSS), and 3-to-6 months modified Rankin Scale scores. Using voxel-based lesion symptom mapping techniques, including age, sex, and diffusion-weighted magnetic resonance imaging lesion volume as covariates, statistical maps were calculated to determine the significance of lesion location for clinical outcome and admission stroke severity. Four hundred ninety subjects were analyzed. Acute stroke lesions in the left hemisphere were associated with more severe NIHSS at admission and poor modified Rankin Scale at 3 to 6 months. Specifically, injury to white matter (corona radiata, internal and external capsules, superior longitudinal fasciculus, and uncinate fasciculus), postcentral gyrus, putamen, and operculum were implicated in poor modified Rankin Scale. More severe NIHSS involved these regions, as well as the amygdala, caudate, pallidum, inferior frontal gyrus, insula, and precentral gyrus. Acute lesion topography provides important insights into anatomic correlates of admission stroke severity and poststroke outcomes. Future models that account for infarct location in addition to diffusion-weighted magnetic resonance imaging volume may improve stroke outcome prediction and identify patients likely to benefit from aggressive acute intervention and personalized rehabilitation strategies. © 2015 American Heart Association, Inc.

  20. Changes in intracranial pressure gradients between the cerebral hemispheres in patients with intracerebral hematomas in one cerebral hemisphere.

    Science.gov (United States)

    Qiu, Wusi; Jiang, Qizhou; Xiao, Guoming; Wang, Weiming; Shen, Hong

    2014-01-01

    Intracranial-pressure (ICP) monitoring is useful for patients with increased ICP following hemorrhagic stroke. In this study, the changes in pressure gradients between the two cerebral hemispheres were investigated after hemorrhagic stroke of one side, and after a craniotomy. Twenty-four patients with acute cerebral hemorrhages and intracerebral hematomas who exhibited mass effect and midline shift to the contralateral side on computed tomography were selected for this study. After admission, both sides of the cranium were drilled, and optical fiber sensors were implanted to monitor the brain parenchyma pressure (BPP) in both cerebral hemispheres. All patients underwent surgical hematoma evacuations. The preoperative and postoperative BPP data from both cerebral hemispheres were collected at various time points and compared pairwise. There were statistically significant differences (P 0.05). The posteroperative BPPs of both hemispheres were statistically significantly lower than preoperative recordings. BPP sensors should be applied to the injured cerebral hemisphere, because this becomes the source of increased ICP. Hematoma evacuation surgery effectively decreases ICP and eliminates pressure gradients between the two cerebral hemispheres, consequently enabling brain shift correction.

  1. Reading the wrong way with the right hemisphere.

    Science.gov (United States)

    Waldie, Karen E; Haigh, Charlotte E; Badzakova-Trajkov, Gjurgjica; Buckley, Jude; Kirk, Ian J

    2013-07-17

    Reading is a complex process, drawing on a variety of brain functions in order to link symbols to words and concepts. The three major brain areas linked to reading and phonological analysis include the left temporoparietal region, the left occipitotemporal region and the inferior frontal gyrus. Decreased activation of the left posterior language system in dyslexia is well documented but there is relatively limited attention given to the role of the right hemisphere. The current study investigated differences in right and left hemisphere activation between individuals with dyslexia and non-impaired readers in lexical decision tasks (regular words, irregular words, pseudowords) during functional Magnetic Resonance Imaging (fMRI). Results revealed the expected hypo-activation in the left posterior areas in those with dyslexia but also areas of overactivation in the right hemisphere. During pseudoword decisions, for example, adults with dyslexia showed more right inferior occipital gyrus activation than controls. In general the increased activation of left-hemisphere language areas found in response to both regular and pseudowords was absent in dyslexics. Laterality indices showed that while controls showed left lateralised activation of the temporal lobe during lexical decision making, dyslexic readers showed right activation. Findings will inform theories of reading and will have implications for the design of reading interventions.

  2. Reading the Wrong Way with the Right Hemisphere

    Directory of Open Access Journals (Sweden)

    Ian J. Kirk

    2013-07-01

    Full Text Available Reading is a complex process, drawing on a variety of brain functions in order to link symbols to words and concepts. The three major brain areas linked to reading and phonological analysis include the left temporoparietal region, the left occipitotemporal region and the inferior frontal gyrus. Decreased activation of the left posterior language system in dyslexia is well documented but there is relatively limited attention given to the role of the right hemisphere. The current study investigated differences in right and left hemisphere activation between individuals with dyslexia and non-impaired readers in lexical decision tasks (regular words, irregular words, pseudowords during functional Magnetic Resonance Imaging (fMRI. Results revealed the expected hypo-activation in the left posterior areas in those with dyslexia but also areas of overactivation in the right hemisphere. During pseudoword decisions, for example, adults with dyslexia showed more right inferior occipital gyrus activation than controls. In general the increased activation of left-hemisphere language areas found in response to both regular and pseudowords was absent in dyslexics. Laterality indices showed that while controls showed left lateralised activation of the temporal lobe during lexical decision making, dyslexic readers showed right activation. Findings will inform theories of reading and will have implications for the design of reading interventions.

  3. Hemispheric asymmetry and theory of mind: is there an association?

    Science.gov (United States)

    Herzig, Daniela A; Sullivan, Sarah; Evans, Jonathan; Corcoran, Rhiannon; Mohr, Christine

    2012-01-01

    In autism and schizophrenia attenuated/atypical functional hemispheric asymmetry and theory of mind impairments have been reported, suggesting common underlying neuroscientific correlates. We here investigated whether impaired theory of mind performance is associated with attenuated/atypical hemispheric asymmetry. An association may explain the co-occurrence of both dysfunctions in psychiatric populations. Healthy participants (n=129) performed a left hemisphere (lateralised lexical decision task) and right hemisphere (lateralised face decision task) dominant task as well as a visual cartoon task to assess theory of mind performance. Linear regression analyses revealed inconsistent associations between theory of mind performance and functional hemisphere asymmetry: enhanced theory of mind performance was only associated with (1) faster right hemisphere language processing, and (2) reduced right hemisphere dominance for face processing (men only). The majority of non-significant findings suggest that theory of mind and functional hemispheric asymmetry are unrelated. Instead of "overinterpreting" the two significant results, discrepancies in the previous literature relating to the problem of the theory of mind concept, the variety of tasks, and the lack of normative data are discussed. We also suggest how future studies could explore a possible link between hemispheric asymmetry and theory of mind.

  4. Altered resting-state network connectivity in stroke patients with and without apraxia of speech.

    Science.gov (United States)

    New, Anneliese B; Robin, Donald A; Parkinson, Amy L; Duffy, Joseph R; McNeil, Malcom R; Piguet, Olivier; Hornberger, Michael; Price, Cathy J; Eickhoff, Simon B; Ballard, Kirrie J

    2015-01-01

    Motor speech disorders, including apraxia of speech (AOS), account for over 50% of the communication disorders following stroke. Given its prevalence and impact, and the need to understand its neural mechanisms, we used resting state functional MRI to examine functional connectivity within a network of regions previously hypothesized as being associated with AOS (bilateral anterior insula (aINS), inferior frontal gyrus (IFG), and ventral premotor cortex (PM)) in a group of 32 left hemisphere stroke patients and 18 healthy, age-matched controls. Two expert clinicians rated severity of AOS, dysarthria and nonverbal oral apraxia of the patients. Fifteen individuals were categorized as AOS and 17 were AOS-absent. Comparison of connectivity in patients with and without AOS demonstrated that AOS patients had reduced connectivity between bilateral PM, and this reduction correlated with the severity of AOS impairment. In addition, AOS patients had negative connectivity between the left PM and right aINS and this effect decreased with increasing severity of non-verbal oral apraxia. These results highlight left PM involvement in AOS, begin to differentiate its neural mechanisms from those of other motor impairments following stroke, and help inform us of the neural mechanisms driving differences in speech motor planning and programming impairment following stroke.

  5. Altered resting-state network connectivity in stroke patients with and without apraxia of speech

    Directory of Open Access Journals (Sweden)

    Anneliese B. New

    2015-01-01

    Full Text Available Motor speech disorders, including apraxia of speech (AOS, account for over 50% of the communication disorders following stroke. Given its prevalence and impact, and the need to understand its neural mechanisms, we used resting state functional MRI to examine functional connectivity within a network of regions previously hypothesized as being associated with AOS (bilateral anterior insula (aINS, inferior frontal gyrus (IFG, and ventral premotor cortex (PM in a group of 32 left hemisphere stroke patients and 18 healthy, age-matched controls. Two expert clinicians rated severity of AOS, dysarthria and nonverbal oral apraxia of the patients. Fifteen individuals were categorized as AOS and 17 were AOS-absent. Comparison of connectivity in patients with and without AOS demonstrated that AOS patients had reduced connectivity between bilateral PM, and this reduction correlated with the severity of AOS impairment. In addition, AOS patients had negative connectivity between the left PM and right aINS and this effect decreased with increasing severity of non-verbal oral apraxia. These results highlight left PM involvement in AOS, begin to differentiate its neural mechanisms from those of other motor impairments following stroke, and help inform us of the neural mechanisms driving differences in speech motor planning and programming impairment following stroke.

  6. Evolution of changes in the computed tomography scans of the brain of a patient with left middle cerebral artery infarction: a case report.

    Science.gov (United States)

    John, Kurien; Singhal, Parag; Cook, Chris

    2008-05-08

    Stroke is a common and important condition in medicine. Effective early management of acute stroke can reduce morbidity and mortality. A 63-year-old man presented to the Accident and Emergency department with a history of collapse and progressive right-sided weakness. Clinically this was a cerebrovascular accident affecting the left hemisphere of the brain causing right hemiplegia. Computed tomography scans, performed 3 days apart, showed the evolution of infarction in the brain caused by the thrombus in the left middle cerebral artery. This is one of the early signs for stroke seen on computed tomography imaging and it is called the hyperdense middle cerebral artery sign. Patients admitted with a stroke, undergo CT brain within 24 hours. The scan usually takes place at admission into the hospital and is done to rule out a bleed or a space occupying lesion within the brain. A normal CT brain does not confirm a stroke has not taken place. When scanned early, the changes seen on the CT due to an infarction from a thrombus may not have taken place yet. This paper highlights the early changes that can be seen on the CT brain following a stroke caused by infarction due to a thrombus in the middle cerebral artery.

  7. Hemispheric asymmetry in the influence of language on visual perception.

    Science.gov (United States)

    Sun, Yanliang; Cai, Yongchun; Lu, Shena

    2015-07-01

    Many studies have shown that language can affect visual perception; however, our understanding of the neural basis of linguistic influence is inadequate. This can be investigated by examining the hemispheric asymmetry of linguistic influence. The left and right hemispheres are dominant in close and distant semantic processing, respectively. In this study, we investigated whether the hemispheric asymmetry of semantic processing led to hemispheric asymmetry for concept priming on the detection of objects degraded by continuous flash suppression. We combined a priming paradigm with the divided visual field paradigm and used continuous flash suppression, which renders objects invisible. The results indicated that the hemispheric asymmetry of semantic processing led to a right lateralization in the influence of more abstract concepts on visual perception. The lateralization of brain connectomes may be the underlying neural basis of this effect. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. A Preliminary fMRI Study of a Novel Self-Paced Written Fluency Task: Observation of Left-Hemispheric Activation, and Increased Frontal Activation in Late vs. Early Task Phases

    Directory of Open Access Journals (Sweden)

    Laleh eGolestanirad

    2015-03-01

    Full Text Available Neuropsychological tests of verbal fluency are very widely used to characterize impaired cognitive function. For clinical neuroscience studies and potential medical applications, measuring the brain activity that underlies such tests with functional magnetic resonance imaging (fMRI is of significant interest - but a challenging proposition because overt speech can cause signal artifacts, which tend to worsen as the duration of speech tasks becomes longer. In a novel approach, we present the group brain activity of 12 subjects who performed a self-paced written version of phonemic fluency using fMRI-compatible tablet technology that recorded responses and provided task-related feedback on a projection screen display, over long-duration task blocks (60 s. As predicted, we observed robust activation in the left anterior inferior and medial frontal gyri, consisting with previously reported results of verbal fluency tasks which established the role of these areas in strategic word retrieval. In addition, the number of words produced in the late phase (last 30 s of written phonemic fluency was significantly less (p < 0.05 than the number produced in the early phase (first 30 s. Activation during the late phase vs. the early phase was also assessed from the first 20 s and last 20 s of task performance, which eliminated the possibility that the sluggish hemodynamic response from the early phase would affect the activation estimates of the late phase. The last 20 s produced greater activation maps covering extended areas in bilateral precuneus, cuneus, middle temporal gyrus, insula, middle frontal gyrus and cingulate gyrus. Among them, greater activation was observed in the bilateral middle frontal gyrus (Brodmann area BA 9 and cingulate gyrus (BA 24, 32 likely as part of the initiation, maintenance, and shifting of attentional resources.

  9. A preliminary fMRI study of a novel self-paced written fluency task: observation of left-hemispheric activation, and increased frontal activation in late vs. early task phases.

    Science.gov (United States)

    Golestanirad, Laleh; Das, Sunit; Schweizer, Tom A; Graham, Simon J

    2015-01-01

    Neuropsychological tests of verbal fluency are very widely used to characterize impaired cognitive function. For clinical neuroscience studies and potential medical applications, measuring the brain activity that underlies such tests with functional magnetic resonance imaging (fMRI) is of significant interest-but a challenging proposition because overt speech can cause signal artifacts, which tend to worsen as the duration of speech tasks becomes longer. In a novel approach, we present the group brain activity of 12 subjects who performed a self-paced written version of phonemic fluency using fMRI-compatible tablet technology that recorded responses and provided task-related feedback on a projection screen display, over long-duration task blocks (60 s). As predicted, we observed robust activation in the left anterior inferior and medial frontal gyri, consistent with previously reported results of verbal fluency tasks which established the role of these areas in strategic word retrieval. In addition, the number of words produced in the late phase (last 30 s) of written phonemic fluency was significantly less (p < 0.05) than the number produced in the early phase (first 30 s). Activation during the late phase vs. the early phase was also assessed from the first 20 s and last 20 s of task performance, which eliminated the possibility that the sluggish hemodynamic response from the early phase would affect the activation estimates of the late phase. The last 20 s produced greater activation maps covering extended areas in bilateral precuneus, cuneus, middle temporal gyrus, insula, middle frontal gyrus and cingulate gyrus. Among these areas, greater activation was observed in the bilateral middle frontal gyrus (Brodmann area BA 9) and cingulate gyrus (BA 24, 32) likely as part of the initiation, maintenance, and shifting of attentional resources. Consistent with previous pertinent fMRI literature involving overt and covert verbal responses, these findings highlight the

  10. Remote Lower White Matter Integrity Increases the Risk of Long-Term Cognitive Impairment After Ischemic Stroke in Young Adults.

    Science.gov (United States)

    Schaapsmeerders, Pauline; Tuladhar, Anil M; Arntz, Renate M; Franssen, Sieske; Maaijwee, Noortje A M; Rutten-Jacobs, Loes C A; Schoonderwaldt, Hennie C; Dorresteijn, Lucille D A; van Dijk, Ewoud J; Kessels, Roy P C; de Leeuw, Frank-Erik

    2016-10-01

    Poststroke cognitive impairment occurs frequently in young patients with ischemic stroke (18 through 50 years of age). Accumulating data suggest that stroke is associated with lower white matter integrity remote from the stroke impact area, which might explain why some patients have good long-term cognitive outcome and others do not. Given the life expectancy of decades in young patients, we therefore investigated remote white matter in relation to long-term cognitive function. We included all consecutive first-ever ischemic stroke patients, left/right hemisphere, without recurrent stroke or transient ischemic attack during follow-up, aged 18 through 50 years, admitted to our university medical center between 1980 and 2010. One hundred seventeen patients underwent magnetic resonance imaging scanning including a T1-weighted scan, a diffusion tensor imaging scan, and completed a neuropsychological assessment. Patients were compared with a matched stroke-free control group (age, sex, and education matched). Cognitive impairment was defined as >1.5 SD below the mean cognitive index score of controls and no cognitive impairment as ≤1 SD. Tract-Based Spatial Statistics was used to assess the white matter integrity (fractional anisotropy and mean diffusivity). About 11 years after ischemic stroke, lower remote white matter integrity was associated with a worse long-term cognitive performance. A lower remote white matter integrity, even in the contralesional hemisphere, was observed in cognitively impaired patients (n=25) compared with cognitively unimpaired patients (n=71). These findings indicate that although stroke has an acute onset, it might have long lasting effects on remote white matter integrity and thereby increases the risk of long-term cognitive impairment. © 2016 American Heart Association, Inc.

  11. Improving left spatial neglect through music scale playing.

    Science.gov (United States)

    Bernardi, Nicolò Francesco; Cioffi, Maria Cristina; Ronchi, Roberta; Maravita, Angelo; Bricolo, Emanuela; Zigiotto, Luca; Perucca, Laura; Vallar, Giuseppe

    2017-03-01

    The study assessed whether the auditory reference provided by a music scale could improve spatial exploration of a standard musical instrument keyboard in right-brain-damaged patients with left spatial neglect. As performing music scales involves the production of predictable successive pitches, the expectation of the subsequent note may facilitate patients to explore a larger extension of space in the left affected side, during the production of music scales from right to left. Eleven right-brain-damaged stroke patients with left spatial neglect, 12 patients without neglect, and 12 age-matched healthy participants played descending scales on a music keyboard. In a counterbalanced design, the participants' exploratory performance was assessed while producing scales in three feedback conditions: With congruent sound, no-sound, or random sound feedback provided by the keyboard. The number of keys played and the timing of key press were recorded. Spatial exploration by patients with left neglect was superior with congruent sound feedback, compared to both Silence and Random sound conditions. Both the congruent and incongruent sound conditions were associated with a greater deceleration in all groups. The frame provided by the music scale improves exploration of the left side of space, contralateral to the right hemisphere, damaged in patients with left neglect. Performing a scale with congruent sounds may trigger at some extent preserved auditory and spatial multisensory representations of successive sounds, thus influencing the time course of space scanning, and ultimately resulting in a more extensive spatial exploration. These findings offer new perspectives also for the rehabilitation of the disorder. © 2015 The British Psychological Society.

  12. From the Left to the Right: How the Brain Compensates Progressive Loss of Language Function

    Science.gov (United States)

    Thiel, Alexander; Habedank, Birgit; Herholz, Karl; Kessler, Josef; Winhuisen, Lutz; Haupt, Walter F.; Heiss, Wolf-Dieter

    2006-01-01

    In normal right-handed subjects language production usually is a function of the left brain hemisphere. Patients with aphasia following brain damage to the left hemisphere have a considerable potential to compensate for the loss of this function. Sometimes, but not always, areas of the right hemisphere which are homologous to language areas of the…

  13. The Impact of Left and Right Intracranial Tumors on Picture and Word Recognition Memory

    Science.gov (United States)

    Goldstein, Bram; Armstrong, Carol L.; Modestino, Edward; Ledakis, George; John, Cameron; Hunter, Jill V.

    2004-01-01

    This study investigated the effects of left and right intracranial tumors on picture and word recognition memory. We hypothesized that left hemispheric (LH) patients would exhibit greater word recognition memory impairment than right hemispheric (RH) patients, with no significant hemispheric group picture recognition memory differences. The LH…

  14. Motivation and motor control: hemispheric specialization for approach motivation reverses with handedness.

    Directory of Open Access Journals (Sweden)

    Geoffrey Brookshire

    Full Text Available BACKGROUND: According to decades of research on affective motivation in the human brain, approach motivational states are supported primarily by the left hemisphere and avoidance states by the right hemisphere. The underlying cause of this specialization, however, has remained unknown. Here we conducted a first test of the Sword and Shield Hypothesis (SSH, according to which the hemispheric laterality of affective motivation depends on the laterality of motor control for the dominant hand (i.e., the "sword hand," used preferentially to perform approach actions and the nondominant hand (i.e., the "shield hand," used preferentially to perform avoidance actions. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether the laterality of approach motivation varies with handedness, we measured alpha-band power (an inverse index of neural activity in right- and left-handers during resting-state electroencephalography and analyzed hemispheric alpha-power asymmetries as a function of the participants' trait approach motivational tendencies. Stronger approach motivation was associated with more left-hemisphere activity in right-handers, but with more right-hemisphere activity in left-handers. CONCLUSIONS: The hemispheric correlates of approach motivation reversed between right- and left-handers, consistent with the way they typically use their dominant and nondominant hands to perform approach and avoidance actions. In both right- and left-handers, approach motivation was lateralized to the same hemisphere that controls the dominant hand. This covariation between neural systems for action and emotion provides initial support for the SSH.

  15. Prognostic Value of Cortically Induced Motor Evoked Activity by TMS in Chronic Stroke: Caveats from a Revealing Single Clinical Case

    LENUS (Irish Health Repository)

    Amengual, Julià L

    2012-06-08

    AbstractBackgroundWe report the case of a chronic stroke patient (62 months after injury) showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS) of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand.Case presentationMultimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP), and Cortical Silent period (CSP) as well as functional magnetic resonance imaging (fMRI) of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI) Tractography of corticospinal tract (CST). Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG) activity (indexed by CSP) demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations.ConclusionsThe potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.

  16. Post-stroke language disorders.

    Science.gov (United States)

    Sinanović, Osman; Mrkonjić, Zamir; Zukić, Sanela; Vidović, Mirjana; Imamović, Kata

    2011-03-01

    Post-stroke language disorders are frequent and include aphasia, alexia, agraphia and acalculia. There are different definitions of aphasias, but the most widely accepted neurologic and/or neuropsychological definition is that aphasia is a loss or impairment of verbal communication, which occurs as a consequence of brain dysfunction. It manifests as impairment of almost all verbal abilities, e.g., abnormal verbal expression, difficulties in understanding spoken or written language, repetition, naming, reading and writing. During the history, many classifications of aphasia syndromes were established. For practical use, classification of aphasias according to fluency, comprehension and abilities of naming it seems to be most suitable (nonfluent aphasias: Broca's, transcortical motor, global and mixed transcortical aphasia; fluent aphasias: anomic, conduction, Wernicke's, transcortical sensory, subcortical aphasia). Aphasia is a common consequence of left hemispheric lesion and most common neuropsychological consequence of stroke, with a prevalence of one-third of all stroke patients in acute phase, although there are reports on even higher figures. Many speech impairments have a tendency of spontaneous recovery. Spontaneous recovery is most remarkable in the first three months after stroke onset. Recovery of aphasias caused by ischemic stroke occurs earlier and it is most intensive in the first two weeks. In aphasias caused by hemorrhagic stroke, spontaneous recovery is slower and occurs from the fourth to the eighth week after stroke. The course and outcome of aphasia depend greatly on the type of aphasia. Regardless of the fact that a significant number of aphasias spontaneously improve, it is necessary to start treatment as soon as possible. The writing and reading disorders in stroke patients (alexias and agraphias) are more frequent than verified on routine examination, not only in less developed but also in large neurologic departments. Alexia is an acquired

  17. Emotion recognition and marital satisfaction in stroke.

    Science.gov (United States)

    Blonder, Lee X; Pettigrew, L Creed; Kryscio, Richard J

    2012-01-01

    Deficits in the comprehension of facial and prosodic expressions are commonly associated with right hemisphere stroke. However, little is known regarding the impact of these disorders on social relations. We examined facial and prosodic processing, mood, and marital satisfaction in 12 right hemisphere damaged (RHD) stroke patients and nine controls. Results revealed significant impairments in the comprehension of facial expressions and prosody among RHD stroke patients. Nonparametric correlations in the RHD group showed significant associations between marital satisfaction and facial affect discrimination and matching, and nonaffective prosody discrimination. We conclude that deficits in the recognition of nonverbal expressions are associated with reduced relationship satisfaction.

  18. Opposed hemispheric specializations for human hypersexuality and orgasm?

    Science.gov (United States)

    Suffren, Sabrina; Braun, Claude M J; Guimond, Anik; Devinsky, Orrin

    2011-05-01

    With a multiple case report analysis we demonstrate that hypersexuality more often results from right hemisphere (RH) (n=26) than left hemisphere (LH) (n=7) lesions, possibly because of LH release after the RH lesion, and that ictal orgasm more often occurs in patients with right-sided (n=23) than left-sided (n=8) seizure foci, with the symptom probably resulting from RH activation. The LH may be specialized for increasing sexual tension, whereas the RH may be specialized for release of this tension (orgasm), the former being catabolic and the latter anabolic. Several other interpretations of the findings are also discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Reduced contralateral hemispheric flow measured by SPECT in cerebellar lesions

    DEFF Research Database (Denmark)

    Sönmezoğlu, K; Sperling, B; Henriksen, T

    1993-01-01

    Four patients with clinical signs of cerebellar stroke were studied twice by SPECT using 99mTc-HMPAO as a tracer for cerebral blood flow (CBF). When first scanned 6 to 22 days after onset, all had a region of very low CBF in the symptomatic cerebellar hemisphere, and a mild to moderate CBF...... reduction (average 10%) in contralateral hemispheric cortex. In all four cases clinical signs of unilateral cerebellar dysfunction were still present when rescanned 1 to 4 months later and the relative CBF decrease in the contralateral cortex of the forebrain also remained. The basal ganglia contralateral...

  20. Stroke rehabilitation: recent advances and future therapies.

    LENUS (Irish Health Repository)

    Brewer, L

    2012-09-27

    Despite advances in the acute management of stroke, a large proportion of stroke patients are left with significant impairments. Over the coming decades the prevalence of stroke-related disability is expected to increase worldwide and this will impact greatly on families, healthcare systems and economies. Effective neuro-rehabilitation is a key factor in reducing disability after stroke. In this review, we discuss the effects of stroke, principles of stroke rehabilitative care and predictors of recovery. We also discuss novel therapies in stroke rehabilitation, including non-invasive brain stimulation, robotics and pharmacological augmentation. Many trials are currently underway, which, in time, may impact on future rehabilitative practice.

  1. Reversing dobutamine-induced tachycardia using ivabradine increases stroke volume with neutral effect on cardiac energetics in left ventricular post-ischaemia dysfunction.

    Science.gov (United States)

    Bakkehaug, J P; Naesheim, T; Torgersen Engstad, E; Kildal, A B; Myrmel, T; How, O-J

    2016-10-01

    Compensatory tachycardia can potentially be deleterious in acute heart failure. In this study, we tested a therapeutic strategy of combined inotropic support (dobutamine) and selective heart rate (HR) reduction through administration of ivabradine. In an open-chest pig model (n = 12) with left ventricular (LV) post-ischaemia dysfunction, cardiac function was assessed by LV pressure catheter and sonometric crystals. Coronary flow and blood samples from the coronary sinus were used to measure myocardial oxygen consumption (MVO2 ). LV energetics was assessed by comparing MVO2 with cardiac work at a wide range of workloads. In the post-ischaemia heart, dobutamine (5 μg kg(-1)  min(-1) ) increased cardiac output (CO) by increasing HR from 102 ± 21 to 131 ± 16 bpm (beats per min; P efficiency. Similar findings on efficiency and LV function were also seen using an ex vivo working mouse heart protocol. A combined infusion of dobutamine and ivabradine had a neutral effect on post-ischaemia LV efficiency and increased left ventricular output without an increase in HR. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  2. The left superior temporal gyrus is a shared substrate for auditory short-term memory and speech comprehension: evidence from 210 patients with stroke.

    Science.gov (United States)

    Leff, Alexander P; Schofield, Thomas M; Crinion, Jennifer T; Seghier, Mohamed L; Grogan, Alice; Green, David W; Price, Cathy J

    2009-12-01

    Competing theories of short-term memory function make specific predictions about the functional anatomy of auditory short-term memory and its role in language comprehension. We analysed high-resolution structural magnetic resonance images from 210 stroke patients and employed a novel voxel based analysis to test the relationship between auditory short-term memory and speech comprehension. Using digit span as an index of auditory short-term memory capacity we found that the structural integrity of a posterior region of the superior temporal gyrus and sulcus predicted auditory short-term memory capacity, even when performance on a range of other measures was factored out. We show that the integrity of this region also predicts the ability to comprehend spoken sentences. Our results therefore support cognitive models that posit a shared substrate between auditory short-term memory capacity and speech comprehension ability. The method applied here will be particularly useful for modelling structure-function relationships within other complex cognitive domains.

  3. Cohesive and coherent connected speech deficits in mild stroke.

    Science.gov (United States)

    Barker, Megan S; Young, Breanne; Robinson, Gail A

    2017-05-01

    Spoken language production theories and lesion studies highlight several important prelinguistic conceptual preparation processes involved in the production of cohesive and coherent connected speech. Cohesion and coherence broadly connect sentences with preceding ideas and the overall topic. Broader cognitive mechanisms may mediate these processes. This study aims to investigate (1) whether stroke patients without aphasia exhibit impairments in cohesion and coherence in connected speech, and (2) the role of attention and executive functions in the production of connected speech. Eighteen stroke patients (8 right hemisphere stroke [RHS]; 6 left [LHS]) and 21 healthy controls completed two self-generated narrative tasks to elicit connected speech. A multi-level analysis of within and between-sentence processing ability was conducted. Cohesion and coherence impairments were found in the stroke group, particularly RHS patients, relative to controls. In the whole stroke group, better performance on the Hayling Test of executive function, which taps verbal initiation/suppression, was related to fewer propositional repetitions and global coherence errors. Better performance on attention tasks was related to fewer propositional repetitions, and decreased global coherence errors. In the RHS group, aspects of cohesive and coherent speech were associated with better performance on attention tasks. Better Hayling Test scores were related to more cohesive and coherent speech in RHS patients, and more coherent speech in LHS patients. Thus, we documented connected speech deficits in a heterogeneous stroke group without prominent aphasia. Our results suggest that broader cognitive processes may play a role in producing connected speech at the early conceptual preparation stage. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. A new clinical sign probably associated to left hemiplegia with left hemineglect syndrome: the crossed legs.

    Science.gov (United States)

    Bazan, Rodrigo; Fernandes, Thiago; Braga, Gabriel; Luvizutto, Gustavo; Resende, Luiz

    2014-06-01

    To describe a new clinical sign associated with left unilateral neglect syndrome (UNS) in patients with ischemic stroke. Head computed tomography (CT) and National Institute of Health Stroke Scale were obtained in 150 patients with ischemic stroke. Those with right cerebral vascular lesions, left hemiplegia and right leg persistently crossed over the left were submitted to specific tests for UNS. The tests were also applied to 30 patients with right cerebral vascular lesions, left hemiplegia but without crossed legs. From 9 patients with persistent tendency to cross the right leg over the left, UNS was detected in 8. One patient died before the clinical tests were applied. Of the 30 patients without the crossed legs, 20 had normal clinical tests for UNS and 10 had minimal alterations, not sufficient for the diagnosis of UNS. The right leg crossed over the left may represent a new neurological semiotic sign associated with left hemiplegia and left UNS.

  5. Tomada de decisão no IGT: estudo de caso pós-AVC de hemisfério direito versus esquerdo Toma de decisión en el IGT: estudio de caso post-AVC de hemisferio derecho versus isquierdo Decision making in IGT: a case study of post-CVA of left versus right hemisphere

    Directory of Open Access Journals (Sweden)

    Caroline de Oliveira Cardoso

    2012-04-01

    decision-making process of two post-unilateral CVA adults as well as verifying the role of hemispheric laterality in the performance of Iowa Gambling Task (IGT. One adult with right hemisphere damage (RHD and another with left hemisphere damage (LHD, both following a subcortical ischemic post-CVA. The IGT was used to evaluate the decision making. Patients had appropriate performance on the IGT suggesting a general good ability to make decisions. However, only the patient with LHD presented signs of ascendant learning curve. Conclusion: These data indicate that a subcortical lesion independent of the hemisphere may not influence on the IGT performance. It is suggested that comparative studies of groups should be conducted in order to compare patients with frontal and non-frontal lesions, helping to characterize the decision-making process in population with unilateral vascular damage.

  6. Lateral thinkers are not so laterally minded: hemispheric asymmetry, interaction, and creativity.

    Science.gov (United States)

    Lindell, Annukka K

    2011-07-01

    The biological basis of creativity remains a topic of contention. A long-held view suggests that whereas the left hemisphere is intelligent and analytic, the right hemisphere is the source of all creativity. Consequently, activating the right hemisphere should enhance creative thinking, prompting a plethora of popular books hawking a right hemisphere solution to topics ranging from drawing, to money management, to sex. More recently, an alternate proposal has suggested that creativity is not a lateralised function; instead, creativity is argued to stem from the interaction and integration of information across both the left and right hemispheres. According to this view, individuals with greater interhemispheric communication and/or less-lateralised brains will evidence enhanced creative ability. This paper reviews the neural basis of creativity to determine whether creativity stems from activation of the right hemisphere, or from the interaction of both hemispheres. The relationship between creativity and psychopathology is also examined, evaluating the evidence for a causal link between disorders such as schizophrenia, hemispheric activation, and enhanced creativity. Although the research reviewed indicates greater right hemisphere activity during creative tasks, the interaction between many varied, often distant, cortical regions across both the left and right hemispheres is also a crucial component of creativity. This interaction facilitates the integration of a variety of separate cognitive abilities, fostering creative thinking. As such, creativity is better conceptualised as a distributed, rather than a purely lateralised, function; more lateral thinkers have less lateralised brains.

  7. Individual differences in hemispheric preference and emotion regulation difficulties

    Directory of Open Access Journals (Sweden)

    Garima Gupta

    2011-01-01

    Full Text Available Background: Hemisphericity or individual difference in the preference to use the left or the right hemispheric mode of information processing has been associated with various emotion-related differences. For example, the right hemisphericity has been linked with inhibition of emotional expression, feeling of tension, greater impulsivity etc. These observations suggest that right hemisphericity may be associated with greater difficulties in regulating emotions. However, direct empirical tests of such theoretical proposition are very thin. Aim: In view of this, the present study aims to investigate how and to what extent individual difference in hemispheric preference relate to emotion regulation. Materials and Methods: Thirty-two right-handed male subjects in the age range 18 to 20 years were assessed on self-report measures of hemispheric preference and emotion regulation difficulties. The correlation between dimensions of hemispheric preference and difficulties in regulating emotions was computed. A series of stepwise multiple regression analyses were also done to explore the relative significance of various dimensions of hemispheric preference in predicting emotion regulation difficulties. Results: The findings revealed that in general a preference for the right hemispheric mode of information processing was associated with greater emotion regulation difficulties. The correlation analysis indicated that while impulse control difficulties and difficulties in engaging goal directed behavior was associated with preference for almost all the right hemispheric mode of information processing, the nonacceptance of emotional responses and limited access to emotion regulation was related to preference for only global/synthetic (a right hemispheric mode of information processing. Similarly, the lack of emotional clarity facet of emotion regulation difficulties correlated significantly with a preference for the emotional mode of information processing

  8. Intensive therapy induces contralateral white matter changes in chronic stroke patients with Broca's aphasia.

    Science.gov (United States)

    Wan, Catherine Y; Zheng, Xin; Marchina, Sarah; Norton, Andrea; Schlaug, Gottfried

    2014-09-01

    Using a pre-post design, eleven chronic stroke patients with large left hemisphere lesions and nonfluent aphasia underwent diffusion tensor imaging and language testing before and after receiving 15 weeks of an intensive intonation-based speech therapy. This treated patient group was compared to an untreated patient group (n=9) scanned twice over a similar time period. Our results showed that the treated group, but not the untreated group, had reductions in fractional anisotropy in the white matter underlying the right inferior frontal gyrus (IFG, pars opercularis and pars triangularis), the right posterior superior temporal gyrus, and the right posterior cingulum. Furthermore, we found that greater improvements in speech production were associated with greater reductions in FA in the right IFG (pars opercularis). Thus, our findings showed that an intensive rehabilitation program for patients with nonfluent aphasia led to structural changes in the right hemisphere, which correlated with improvements in speech production. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Intensive therapy induces contralateral white matter changes in chronic stroke patients with Broca’s aphasia

    Science.gov (United States)

    Marchina, Sarah; Norton, Andrea; Schlaug, Gottfried

    2015-01-01

    Using a pre-post design, eleven chronic stroke patients with large left hemisphere lesions and nonfluent aphasia underwent diffusion tensor imaging and language testing before and after receiving 15 weeks of an intensive intonation-based speech therapy. This treated patient group was compared to an untreated patient group (n=9) scanned twice over a similar time period. Our results showed that the treated group, but not the untreated group, had reductions in fractional anisotropy in the white matter underlying the right inferior frontal gyrus (IFG, pars opercularis and pars triangularis), the right posterior superior temporal gyrus, and in the right posterior cingulum. Furthermore, we found that greater improvements in speech production were associated with greater reductions in FA in the right IFG (pars opercularis). Thus, our findings showed that an intensive rehabilitation program for patients with non-fluent aphasia led to structural changes in the right hemisphere, which correlated with improvements in speech production. PMID:25041868

  10. Left Ventricular Stroke Volume Quantification by Contrast Echocardiography – Comparison of Linear and Flow-Based Methods to Cardiac Magnetic Resonance

    Science.gov (United States)

    Dele-Michael, Abiola O.; Fujikura, Kana; Devereux, Richard B; Islam, Fahmida; Hriljac, Ingrid; Wilson, Sean R.; Lin, Fay; Weinsaft, Jonathan W.

    2014-01-01

    Background Echocardiography (echo) quantified LV stroke volume (SV) is widely used to assess systolic performance after acute myocardial infarction (AMI). This study compared two common echo approaches – predicated on flow (Doppler) and linear chamber dimensions (Teichholz) – to volumetric SV and global infarct parameters quantified by cardiac magnetic resonance (CMR). Methods Multimodality imaging was performed as part of a post-AMI registry. For echo, SV was measured by Doppler and Teichholz methods. Cine-CMR was used for volumetric SV and LVEF quantification, and delayed-enhancement CMR for infarct size. Results 142 patients underwent same-day echo and CMR. On echo, mean SV by Teichholz (78±17ml) was slightly higher than Doppler (75±16ml; Δ=3±13ml, p=0.02). Compared to SV on CMR (78±18ml), mean difference by Teichholz (Δ=−0.2±14; p=0.89) was slightly smaller than Doppler (Δ−3±14; p=0.02) but limits of agreement were similar between CMR and echo methods (Teichholz: −28, 27 ml, Doppler: −31, 24ml). For Teichholz, differences with CMR SV were greatest among patients with anteroseptal or lateral wall hypokinesis (p<0.05). For Doppler, differences were associated with aortic valve abnormalities or root dilation (p=0.01). SV by both echo methods decreased stepwise in relation to global LV injury as assessed by CMR-quantified LVEF and infarct size (p<0.01). Conclusions Teichholz and Doppler calculated SV yield similar magnitude of agreement with CMR. Teichholz differences with CMR increase with septal or lateral wall contractile dysfunction, whereas Doppler yields increased offsets in patients with aortic remodeling. PMID:23488864

  11. When One Hemisphere Takes Control: Metacontrol in Pigeons (Columba livia)

    Science.gov (United States)

    Adam, Ruth; Güntürkün, Onur

    2009-01-01

    Background Vertebrate brains are composed of two hemispheres that receive input, compute, and interact to form a unified response. How the partially different processes of both hemispheres are integrated to create a single output is largely unknown. In some cases one hemisphere takes charge of the response selection – a process known as metacontrol. Thus far, this phenomenon has only been shown in a handful of studies with primates, mostly conducted in humans. Metacontrol, however, is even more relevant for animals like birds with laterally placed eyes and complete chiasmatic decussation since visual input to the hemispheres is largely different. Methodology/Principal Findings Homing pigeons (Columba livia) were trained with a color discrimination task. Each hemisphere was trained with a different color pair and therefore had a different experience. Subsequently, the pigeons were binocularly examined with two additional stimuli that combined the positive color of one hemisphere with a negative color that had been shown to the other, omitting the availability of a coherent solution and confronting the pigeons with a conflicting situation. Some of the pigeons responded to both stimuli, indicating that none of the hemispheres dominated the overall preference. Some birds, however, responded primarily to one of the conflicting stimuli, showing that they based their choice on the left- or right-monocularly learned color pair, indicating hemispheric metacontrol. Conclusions/Significance We could demonstrate for the first time that metacontrol is a widespread phenomenon that also exists in birds, and thus in principle requires no corpus callosum. Our results are closely similar to those in humans: monocular performance was higher than binocular one and animals displayed different modes of hemispheric dominance. Thus, metacontrol is a dynamic and widely distributed process that possibly constitutes a requirement for all animals with a bipartite brain to confront the

  12. Quantitative and qualitative hemispheric asymmetry for processing Japanese kana.

    Science.gov (United States)

    Hellige, J B; Yamauchi, M

    1999-08-01

    Native Japanese speakers identified three-letter kana stimuli presented to the left visual field and right hemisphere (LVF/RH), to the right visual field and left hemisphere (RVF/LH), or to both visual fields and hemispheres simultaneously (BILATERAL trials). There were fewer errors on RVF/LH and BILATERAL trials than on LVF/RH trials. Qualitative analysis of error patterns indicated that there were many fewer errors of first-letter identification than of last-letter identification, suggesting top-to-bottom scanning of the kana characters. In contrast to similar studies presenting nonword letter trigrams to native English speakers, qualitative error patterns were identical for the three visual field conditions. Taken together with the results of earlier studies, the results of the present experiment indicate that the ubiquitous RVF/LH advantage reflects a left-hemisphere superiority for phonetic processing that generalizes across specific languages. At the same time, qualitative aspects of hemispheric asymmetry differ from one language to the next and may depend on such things as the way in which individual characters map onto the pronunciation of words and nonwords. Copyright 1999 Academic Press.

  13. Processing of unconventional stimuli requires the recruitment of the non-specialized hemisphere

    Directory of Open Access Journals (Sweden)

    Yoed Nissan Kenett

    2015-02-01

    Full Text Available In the present study we investigate hemispheric processing of conventional and unconventional visual stimuli in the context of visual and verbal creative ability. In Experiment 1, we studied two unconventional visual recognition tasks – Mooney face and objects' silhouette recognition – and found a significant relationship between measures of verbal creativity and unconventional face recognition. In Experiment 2 we used the split visual field paradigm to investigate hemispheric processing of conventional and unconventional faces and its relation to verbal and visual characteristics of creativity. Results showed that while conventional faces were better processed by the specialized right hemisphere, unconventional faces were better processed by the non-specialized left hemisphere. In addition, only unconventional face processing by the non-specialized left hemisphere was related to verbal and visual measures of creative ability. Our findings demonstrate the role of the non-specialized hemisphere in processing unconventional stimuli and how it relates to creativity.

  14. Split Fovea Theory and the Role of the Two Cerebral Hemispheres in Reading: A Review of the Evidence

    Science.gov (United States)

    Ellis, Andrew W.; Brysbaert, Marc

    2010-01-01

    Split fovea theory proposes that when the eyes are fixated within a written word, visual information about the letters falling to the left of fixation is projected initially to the right cerebral hemisphere while visual information about the letters falling to the right of fixation is projected to the left cerebral hemisphere. The two parts of the…

  15. Lateralization of Motor Cortex Excitability in Stroke Patients during Action Observation: A TMS Study

    Directory of Open Access Journals (Sweden)

    Mattia Marangon

    2014-01-01

    Full Text Available Action observation activates the same motor areas as those involved in the performance of the observed actions and promotes functional recovery following stroke. Movement observation is now considered a promising tool for motor rehabilitation, by allowing patients to train their motor functions when voluntary movement is partially impaired. We asked chronic-stroke patients, affected by either left (LHD or right hemisphere (RHD lesions, to observe either a left or right hand, while grasping a small target (eliciting a precision grip or a large target (eliciting a whole hand grasp directed towards a target object. To better understand the effects of action observation on damaged motor circuits, we used transcranial magnetic stimulation (TMS to induce motor evoked potentials (MEP from two muscles of the unaffected hand in 10 completely hemiplegic participants. Results revealed that LHD patients showed MEP facilitation on the right (contralesional M1 during action observation of hand-object interactions. In contrast, results showed no facilitation of the left (contralesional M1 in RHD patients. Our results confirm that action observation might have a positive influence on the recovery of motor functions after stroke. Activating the motor system by means of action observation might provide a mechanism for improving function, at least in LHD patients.

  16. Psychophysiological correlates of dissociation, handedness, and hemispheric lateralization.

    Science.gov (United States)

    Ashworth, Joel; Ciorciari, Joseph; Stough, Con

    2008-05-01

    Dissociation involves a disruption of typically integrated functions including consciousness, information perception, and memory; however, dissociation may not always be of a pathologic nature. Increasingly, studies are identifying relations between inconsistent handedness, mixed hemispheric lateralization, and dissociative symptomatology in both clinical and nonclinical populations. The current study explored whether a nonclinical sample of individuals scoring high in dissociation would display an inconsistent handedness in conjunction with a left hemispheric lateralization as measured by electroencephalography. Twenty-seven participants (12 males and 15 females) aged between 20 and 59 years (M = 29.1 year, SD = 11.2 years), completed the Dissociative Experiences Scale and Waterloo Handedness Questionnaire Revised after determining laterality. As predicted, inconsistently handed participants scoring high in dissociation displayed left hemispheric lateralization across frontal, central, and parietal regions. Conversely, right lateralization was found within Delta frequency band across temporal regions. The study provides a good framework for future research investigating the neurophysiological correlates underpinning dissociative symptomatology.

  17. Emotions and hemispheric specialization.

    Science.gov (United States)

    Kyle, N L

    1988-09-01

    Studies of lateralization and specialization of brain function have increased our understanding of emotional processes in the brain. It has been said that the way in which we understand the emotional interrelatedness of brain layers and segments may have important effects on human society. Earlier studies of brain function, especially of limbic effects, suggested a dichotomous state of affairs between the phylogenetically older brain and the newer cortical areas--between affect and cognition. Such concepts are considered here in the light of specialization studies. From the beginning hemispheric laterality research has implicated emotionality and emotional pathology. It also appears that some limbic functions may be mediated in a lateralized fashion. Neuropsychologists have directed much work toward localization of function from its earliest stage; since the 1960s an emphasis has been on "mapping" of cortical functions in terms of psychopathologic disabilities. Various disability groups have been studied in this way, and it may be concluded that neuropsychologic measures are sensitive to changes in cerebral functioning and may have effective lateralizing and localizing ability under specified conditions. Studies of limbic effects in the brain emphasize their importance in emotional behavior but also their interrelatedness with other structures, for example, the frontal and temporal lobes, and particularly the right hemisphere. Studies of commissurotomy (split-brain) patients tend to bear out these relationships. In split-brain subjects the marked reduction in affective verbal and nonverbal behavior reflects the interruption of transcallosal impulses that normally permit emotional infusion of cortical structures to take place. These effects include verbal, visual, and auditory patterns that mediate the ability to decode complex nonverbal patterns and may result in a reduction of "inner speech," that is, symbollexia. They may further lead to a condition of

  18. Migration of Sparganum of the Frontal Lobe to the Ipsilateral Cerebellar Hemisphere: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Eun A; Choi, See Sung; Jeon, Se Jeong; Kim, Hey Won; Lee, Young Hwan [Wonkwang University Hopital, Iksan (Korea, Republic of)

    2009-05-15

    Most cerebral sparganosis lesions are located in the white matter of the cerebral hemisphere. A few cases of cerebral sparganosis where the sparganum have migrated into the contralateral cerebral hemisphere have been reported. We report a case of cerebral sparganosis where the sparganum migrated from the white matter of the left frontal lobe to the ipsilateral cerebellar hemisphere after failure of surgical removal of the worm

  19. Sleep apnea in stroke: Diagnosis, consequences & treatment

    NARCIS (Netherlands)

    Aaronson, J.A.

    2016-01-01

    Obstructive sleep apnea (OSA) is the most common sleep disorder in stroke, but is often left unrecognized and untreated. When left untreated, OSA is thought to contribute to decreased recovery from stroke. The main objectives of this thesis were 1) to improve early recognition of sleep apnea in

  20. Hemispheric Lateralization of Verbal and Spatial Working Memory during Adolescence

    Science.gov (United States)

    Nagel, Bonnie J.; Herting, Megan M.; Maxwell, Emily C.; Bruno, Richard; Fair, Damien

    2013-01-01

    Adult functional magnetic resonance imaging (fMRI) literature suggests that a left-right hemispheric dissociation may exist between verbal and spatial working memory (WM), respectively. However, investigation of this type has been obscured by incomparable verbal and spatial WM tasks and/or visual inspection at arbitrary thresholds as means to…

  1. Hemispheric lateralization of motor thresholds in relation to stuttering.

    Directory of Open Access Journals (Sweden)

    Per A Alm

    Full Text Available Stuttering is a complex speech disorder. Previous studies indicate a tendency towards elevated motor threshold for the left hemisphere, as measured using transcranial magnetic stimulation (TMS. This may reflect a monohemispheric motor system impairment. The purpose of the study was to investigate the relative side-to-side difference (asymmetry and the absolute levels of motor threshold for the hand area, using TMS in adults who stutter (n = 15 and in controls (n = 15. In accordance with the hypothesis, the groups differed significantly regarding the relative side-to-side difference of finger motor threshold (p = 0.0026, with the stuttering group showing higher motor threshold of the left hemisphere in relation to the right. Also the absolute level of the finger motor threshold for the left hemisphere differed between the groups (p = 0.049. The obtained results, together with previous investigations, provide support for the hypothesis that stuttering tends to be related to left hemisphere motor impairment, and possibly to a dysfunctional state of bilateral speech motor control.

  2. [A clinical case of young, oral combined contraceptive using women, heterozygous carrier of the Factor V (Leiden) which revealed thrombosis of the left internal jugular vein and brain ischemia with cerebral infarction and ischemic stroke].

    Science.gov (United States)

    Kovachev, S; Ramshev, K; Ramsheva, Z; Ivanov, A; Ganovska, A

    2013-01-01

    Thrombophilia is associated with increased risks of venous thrombosis in women taking oral contraceptive preparations. Universal thrombophilia screening in women prior to prescribing oral contraceptive preparations is not supported by current evidence. The case is presented of a 23 year-old women with a personal history of interruption and on the same day started with oral contraceptive (0.03 microg ethynil estradiol - 0.075 microg gestodene), which due on a 18 pill/day to acute headache, increasing vomiting and speaking defects. Physical/neurologic/gynecologic examinations observed a normal status. The MRI and CT revealed thrombosis of the left internal jugular vein and brain ischemia with cerebral infarction and ischemic stroke. The acute therapy of thrombotic findings was accompanied with many tests. The thrombophilia PCR-Real time - test finds heterozygous carrier of the Factor V (Leiden). This case shows the need of large prospective studies that should be undertaken to refine the risks and establish the associations of thrombophilias with venous thrombosis among contraceptive users. The key to a prompt diagnosis is to know the risk factors. The relative value of a thrombophilia screening programme before contraceptive using needs to be established.

  3. Global aphasia as a predictor of mortality in the acute phase of a first stroke

    Directory of Open Access Journals (Sweden)

    F F Oliveira

    2011-01-01

    Full Text Available OBJECTIVE: To establish whether vascular aphasic syndromes can predict stroke outcomes. METHOD: Thirty-seven adults were evaluated for speech and language within 72 hours after a single first-ever ischemic brain lesion, in blind association to CT and/or MR. RESULTS: Speech or language disabilities were found in seven (87.5% of the eight deceased patients and twenty-six (89.7% of the twenty-nine survivors. Global aphasia was identified in eleven patients, all with left hemisphere lesions (nine mute; five deceased, consisting on a risk factor for death in the acute stroke phase (ρ=0.022. Age (z=1.65; ρ>0.09, thrombolysis (ρ=0.591, infarct size (ρ=0.076 and side (ρ=0.649 did not significantly influence survival. Absence of aphasia did not predict a better evolution, regardless of the affected hemisphere. Prevalence of cardiovascular risk factors was similar for all patient groups. CONCLUSION: Global aphasia in acute stroke can adversely affect prognosis, translated into impairment of dominant perisylvian vascular territories, with mutism as an important semiological element.

  4. Preventing stroke

    Science.gov (United States)

    ... A.M. Editorial team. Related MedlinePlus Health Topics Hemorrhagic Stroke Ischemic Stroke Stroke Browse the Encyclopedia A.D. ... any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should ...

  5. Stroke Rehabilitation

    Science.gov (United States)

    A stroke can cause lasting brain damage. People who survive a stroke need to relearn skills they lost because of ... them relearn those skills. The effects of a stroke depend on which area of the brain was ...

  6. Visual attention capacity after right hemisphere lesions

    DEFF Research Database (Denmark)

    Habekost, Thomas; Rostrup, Egill

    2007-01-01

    for both VSTM capacity and ipsilesional processing speed. The study also showed that lesions in a large region of the right hemisphere, including the putamen, insula, and inferior frontal cortex, do not lead to general deficits in the capacity of visual attention. Udgivelsesdato: 2007-Apr-8......Recently there has been a growing interest in visual short-term memory (VSTM) including the neural basis of the function. Processing speed, another main aspect of visual attention capacity, has received less investigation. For both cognitive functions human lesion studies are sparse. We used...... a whole report experiment for estimation of these two parameters in 22 patients with right side stroke. Psychophysical performance was analyzed using Bundesen's [Bundesen, C. (1990). A theory of visual attention. Psychological Review, 97, 523-547] Theory of Visual Attention (TVA) and compared...

  7. Visual attention capacity after right hemisphere lesions

    DEFF Research Database (Denmark)

    Habekost, Thomas; Rostrup, Egill

    2007-01-01

    Recently there has been a growing interest in visual short-term memory (VSTM) including the neural basis of the function. Processing speed, another main aspect of visual attention capacity, has received less investigation. For both cognitive functions human lesion studies are sparse. We used...... a whole report experiment for estimation of these two parameters in 22 patients with right side stroke. Psychophysical performance was analyzed using Bundesen's [Bundesen, C. (1990). A theory of visual attention. Psychological Review, 97, 523-547] Theory of Visual Attention (TVA) and compared...... for both VSTM capacity and ipsilesional processing speed. The study also showed that lesions in a large region of the right hemisphere, including the putamen, insula, and inferior frontal cortex, do not lead to general deficits in the capacity of visual attention. Udgivelsesdato: 2007-Apr-8...

  8. Black-White IQ Discrepancies May Be Related to Differences in Hemisphericity.

    Science.gov (United States)

    Reynolds, Cecil R.; And Others

    1981-01-01

    Wechsler Preschool and Primary Scale of Intelligence (WPPSI) and McCarthy Scales subtests were ranked according to relative reliance on left-cerebral-hemisphere function. Results suggest that black-white IQ discrepancies may be partially explained by differences in hemisphericity. (Author/RD)

  9. Hemispheric Asymmetries in Semantic Processing: Evidence from False Memories for Ambiguous Words

    Science.gov (United States)

    Faust, Miriam; Ben-Artzi, Elisheva; Harel, Itay

    2008-01-01

    Previous research suggests that the left hemisphere (LH) focuses on strongly related word meanings; the right hemisphere (RH) may contribute uniquely to the processing of lexical ambiguity by activating and maintaining a wide range of meanings, including subordinate meanings. The present study used the word-lists false memory paradigm [Roediger,…

  10. Hemispheric Specialization and Creative Thinking: A Meta-Analytic Review of Lateralization of Creativity

    Science.gov (United States)

    Mihov, Konstantin M.; Denzler, Markus; Forster, Jens

    2010-01-01

    In the last two decades research on the neurophysiological processes of creativity has found contradicting results. Whereas most research suggests right hemisphere dominance in creative thinking, left-hemisphere dominance has also been reported. The present research is a meta-analytic review of the literature to establish how creative thinking…

  11. Reliability of a novel paradigm for determining hemispheric lateralization of visuospatial function

    NARCIS (Netherlands)

    Whitehouse, A.J.O.; Badcock, N.A.; Groen, M.A.; Bishop, D.V.M.

    2009-01-01

    In most individuals, language production and visuospatial skills are subserved predominantly by the left and right hemispheres, respectively. Functional Transcranial Doppler (fTCD) provides a noninvasive and relatively low-cost method for measuring functional lateralization. However, while the

  12. Hemispheric biases and the control of visuospatial attention: an ERP study

    Directory of Open Access Journals (Sweden)

    Banich Marie T

    2005-08-01

    Full Text Available Abstract Background We examined whether individual differences in hemispheric utilization can interact with the intrinsic attentional biases of the cerebral hemispheres. Evidence suggests that the hemispheres have competing biases to direct attention contralaterally, with the left hemisphere (LH having a stronger bias than the right hemisphere. There is also evidence that individuals have characteristic biases to utilize one hemisphere more than the other for processing information, which can induce a bias to direct attention to contralateral space. We predicted that LH-biased individuals would display a strong rightward attentional bias, which would create difficulty in selectively attending to target stimuli in the left visual field (LVF as compared to right in the performance of a bilateral flanker task. Results Consistent with our hypothesis, flanker interference effects were found on the N2c event-related brain potential and error rate for LH-biased individuals in the Attend-LVF condition. The error rate effect was correlated with the degree of hemispheric utilization bias for the LH-Bias group. Conclusion We conclude that hemispheric utilization bias can enhance a hemisphere's contralateral attentional bias, at least for individuals with a LH utilization bias. Hemispheric utilization bias may play an important and largely unrecognized role in visuospatial attention.

  13. Motor recovery by improvement of limb-kinetic apraxia in a chronic stroke patient.

    Science.gov (United States)

    Jang, Sung Ho

    2013-01-01

    We report on a chronic stroke patient who showed motor recovery by improvement of limb-kinetic apraxia (LKA) after undergoing intensive rehabilitation for a period of one month, which was demonstrated by diffusion tensor tractography (DTT) and transcranial magnetic stimulation (TMS). A 50-year-old male patient presented with severe paralysis of the left extremities at the onset of thalamic hemorrhage. At thirty months after onset, the patient exhibited moderate weakness of his left upper and lower extremities. In addition, he exhibited a slow, clumsy, and mutilated movement pattern during grasp-release movements of his left hand. During a one-month period of intensive rehabilitation, which was started at thrity months after onset, the patient showed 22% motor recovery of the left extremities. The slow, clumsy, and mutilated movement pattern of the left hand almost disappeared. DTTs of the corticospinal tract (CST) in both hemispheres originated from the cerebral cortex, including the primary motor cortex, and passed along the known CST pathway. The DTT of the right CST was located anterior to the old hemorrhagic lesion. TMS study performed at thirty and thirty-one months after onset showed normal and similar findings for motor evoked potential in terms of latency and amplitude of the left hand muscle. We think that the motor weakness of the left extremities in this patient was mainly ascribed to LKA and that most of the motor recovery during a one-month period of rehabilitation was attributed to improvement of LKA.

  14. Deficits of reach-to-grasp coordination following stroke: Comparison of instructed and natural movements.

    Science.gov (United States)

    Baak, Benjamin; Bock, Otmar; Dovern, Anna; Saliger, Jochen; Karbe, Hans; Weiss, Peter H

    2015-10-01

    The present work evaluates whether stroke-induced deficits of reach-to-grasp movements, established by typical laboratory paradigms, transfer unconditionally to more natural situations. Sixteen patients with a stroke to the motor-dominant left hemisphere and 16 age- and gender-matched healthy control subjects executed grasping movements with their left (ipsilesional, non-dominant) hand. All movements started in the same position, were aimed at the same object positioned in the same location, and were followed by forward displacement of that object along the same path. Twenty movements were performed as a repetitive, externally triggered task executed for their own sake (context L, as in typical laboratory tasks). Twenty movements were performed as part of a self-initiated action sequence aimed at winning a reward (context E, similar to many everyday situations). The kinematics and dynamics of the transport, grasp and manipulation component of each reach-to-grasp movement were quantified by 41 parameters. Analyses of variance yielded a significant effect of Context for 29 parameters, a significant effect of Group for 9 parameters (mostly related to the coupling of hand transport and grip aperture), and a significant interaction for 5 parameters (all related to the coupling of hand transport and grip aperture). The interaction reflected the fact that stroke patients' movement parameters were more abnormal in context E than in context L. Our data indicate that unilateral stroke degrades the grasp-transport coupling, and that stroke-related motor deficits may be more pronounced in a natural than in a laboratory context. Thus, for stroke patients, assessments and rehabilitation regimes should mainly use activities that are as natural as possible. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Crossed Aphasia in a Dextral without “Minor” Hemisphere Signs

    Directory of Open Access Journals (Sweden)

    J. C. Marshall

    1992-01-01

    Full Text Available A case of severe aphasia after right hemisphere stroke, confirmed by CT, in an unambiguously dextral patient is reported. The patient showed no limb apraxia, and performed well on a test of “closure” (Mooney faces. Extensive testing revealed no signs of visuo-spatial neglect. We conclude that “pure” crossed aphasia can occur in the absence of symptoms normally associated with right hemisphere lesions.

  16. Hemispheric lateralization of linguistic prosody recognition in comparison to speech and speaker recognition.

    Science.gov (United States)

    Kreitewolf, Jens; Friederici, Angela D; von Kriegstein, Katharina

    2014-11-15

    Hemispheric specialization for linguistic prosody is a controversial issue. While it is commonly assumed that linguistic prosody and emotional prosody are preferentially processed in the right hemisphere, neuropsychological work directly comparing processes of linguistic prosody and emotional prosody suggests a predominant role of the left hemisphere for linguistic prosody processing. Here, we used two functional magnetic resonance imaging (fMRI) experiments to clarify the role of left and right hemispheres in the neural processing of linguistic prosody. In the first experiment, we sought to confirm previous findings showing that linguistic prosody processing compared to other speech-related processes predominantly involves the right hemisphere. Unlike previous studies, we controlled for stimulus influences by employing a prosody and speech task using the same speech material. The second experiment was designed to investigate whether a left-hemispheric involvement in linguistic prosody processing is specific to contrasts between linguistic prosody and emotional prosody or whether it also occurs when linguistic prosody is contrasted against other non-linguistic processes (i.e., speaker recognition). Prosody and speaker tasks were performed on the same stimulus material. In both experiments, linguistic prosody processing was associated with activity in temporal, frontal, parietal and cerebellar regions. Activation in temporo-frontal regions showed differential lateralization depending on whether the control task required recognition of speech or speaker: recognition of linguistic prosody predominantly involved right temporo-frontal areas when it was contrasted against speech recognition; when contrasted against speaker recognition, recognition of linguistic prosody predominantly involved left temporo-frontal areas. The results show that linguistic prosody processing involves functions of both hemispheres and suggest that recognition of linguistic prosody is based on

  17. Dizziness in stroke

    Directory of Open Access Journals (Sweden)

    M. V. Zamergrad

    2015-01-01

    Full Text Available Differential diagnosis of new-onset acute vestibular vertigo is chiefly made between vestibular neuronitis and stroke. Dizziness in stroke is usually accompanied by other focal neurological symptoms of brainstem and cerebellar involvement. However, stroke may appear as isolated vestibular vertigo in some cases. An analysis of history data and the results of neurovestibular examination and brain magnetic resonance imaging allows stroke to be diagnosed in patients with acute isolated dizziness. The treatment of patients with stroke-induced dizziness involves a wide range of medications for the reduction of the degree of dizziness and unsteadiness and for the secondary prevention of stroke. Vestibular rehabilitation is an important component of treatment. The paper describes an observation of a patient with poorly controlled hypertension, who developed new-onset acute systemic dizziness. Vestibular neuronitis might be presumed to be a peripheral cause of vestibular disorders, by taking into account the absence of additional obvious neurological symptoms (such as pareses, defective sensation, diplopia, etc. and the nature of nystagmus. However, intention tremor in fingernose and heel-knee tests on the left side, a negative Halmagyi test, and results of Romberg’s test could suggest that stroke was a cause ofdizziness.

  18. Shoulder Subluxation and Shoulder-Hand Syndrome After Stroke; Effect of Brain Lesion Location And Side

    Directory of Open Access Journals (Sweden)

    Levent Ediz

    2011-09-01

    Full Text Available Aim: The effect of brain lesion location and involved brain side in the development of shoulder subluxation (SS and shoulder hand syndrome (SHS is still unclear. The aim of the current study was to evaluate the relationships of SS and SHS with brain lesion location and stroke side. Material and Methods: The inpatient files of the hemiplegic patients, who were hospitalized for rehabilitation, were evaluated resrospectively. Brain lesion location and involved hemisphere side were assessed by brain CT at the insult time. Brain lesion location groups were comprised as following 4 groups which included 35 patients in each group. Group I: Small superficial infarct. This type infarcts involve small area infarct (no more than 20 mm in diameter on a cerebral lobe, such as a small right or left frontal lobe infarct. Group II: Large superficial infarct. Infarcts more than 20 mm in diameter on a cerebral lobe or two or more lobes of one cerebral hemisphere, such as a frontoparietal infarct in the left cerebral hemisphere or frontotemporo- parietal infarct in right or left cerebral hemisphere. Group III: Deep  nfarct. Infarcts of the internal capsule, basal ganglia or thalamus. Group IV:  ombination of deep and large superficial infarcts (combined group II+III. Internal capsule or basal ganglia or thalamic infarct combined with fronto-temporal or fronto-parietal or emporoparieto-occipital infarct on one cerebral hemisphere. A total of 140 hemiplegic patients then devided into 2 groups according to the development of SS and/or SHS.Results: A significant correlation was found between brain lesion locations and SS and/or SHS development. The groups with combined deep and large superficial, and large superficial infarcts showed more frequent SS and/or SHS development. Patients with SS and/or SHS had got low stages at baseline in the upper extremity according to upper extremity Brunnstroma level, upper extremity Ashworth stage and low stages of functional

  19. Paediatric stroke

    African Journals Online (AJOL)

    2011-04-02

    Apr 2, 2011 ... Ischemic Stroke Registry yielded an incidence of 3.3 cases per 100 000 children per year, of ... Neonatal stroke. The newborn period confers the highest risk period for childhood ischaemic stroke. Focal patterns of ischaemic brain injury to the perinatal brain are .... family history of young stroke/ thrombosis.

  20. Volumetric hemispheric ratio as a useful tool in personality psychology.

    Science.gov (United States)

    Montag, Christian; Schoene-Bake, Jan-Christoph; Wagner, Jan; Reuter, Martin; Markett, Sebastian; Weber, Bernd; Quesada, Carlos M

    2013-02-01

    The present study investigates the link between volumetric hemispheric ratios (VHRs) and personality measures in N=267 healthy participants using Eysenck's Personality Inventory-Revised (EPQ-R) and the BIS/BAS scales. A robust association between extraversion and VHRs was observed for gray matter in males but not females. Higher gray matter volume in the left than in the right hemisphere was associated with higher extraversion in males. The results are discussed in the context of positive emotionality and laterality of the human brain. Copyright © 2012 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  1. Crossed Non-Dominant Hemisphere Syndrome in a Right-Hander

    Directory of Open Access Journals (Sweden)

    M. Fujimori

    1994-01-01

    Full Text Available A right-handed patient with a large left temporo-parietal infarction manifested various non-dominant hemisphere signs. He had two left-handed children. On neurobehavioural examinations, he did not show aphasia or ideomotor apraxia, but did show hemispatial neglect, spatial agraphia, constructional apraxia, auditory and tactile extinction, anosodiaphoria and affective changes, all of which are usually observed after right hemispheric damage. We conclude that he has a reversed cerebral laterality of cognitive functions and showed crossed non-dominant hemisphere syndrome.

  2. Mapping number to space in the two hemispheres of the avian brain.

    Science.gov (United States)

    Rugani, Rosa; Vallortigara, Giorgio; Regolin, Lucia

    2016-09-01

    Pre-verbal infants and non-human animals associate small numbers with the left space and large numbers with the right space. Birds and primates, trained to identify a given position in a sagittal series of identical positions, whenever required to respond on a left/right oriented series, referred the given position starting from the left end. Here, we extended this evidence by selectively investigating the role of either cerebral hemisphere, using the temporary monocular occlusion technique. In birds, lacking the corpus callosum, visual input is fed mainly to the contralateral hemisphere. We trained 4-day-old chicks to identify the 4th element in a sagittal series of 10 identical elements. At test, the series was identical but left/right oriented. Test was conducted in right monocular, left monocular or binocular condition of vision. Right monocular chicks pecked at the 4th right element; left monocular and binocular chicks pecked at the 4th left element. Data on monocular chicks demonstrate that both hemispheres deal with an ordinal (sequential) task. Data on binocular chicks indicate that the left bias is linked to a right hemisphere dominance, that allocates the attention toward the left hemispace. This constitutes a first step towards understanding the neural basis of number space mapping. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. [Acute surgical treatment of malignant stroke].

    Science.gov (United States)

    Lilja-Cyron, Alexander; Eskesen, Vagn; Hansen, Klaus; Kondziella, Daniel; Kelsen, Jesper

    2016-10-24

    Malignant stroke is an intracranial herniation syndrome caused by cerebral oedema after a large hemispheric or cerebellar stroke. Malignant middle cerebral artery infarction is a devastating disease with a mortality around 80% despite intensive medical treatment. Decompressive craniectomy reduces mortality and improves functional outcome - especially in younger patients (age ≤ 60 years). Decompression of the posterior fossa is a life-saving procedure in patients with malignant cerebellar infarctions and often leads to good neurological outcome.

  4. Lesion mapping in acute stroke aphasia and its implications for recovery.

    Science.gov (United States)

    Forkel, Stephanie J; Catani, Marco

    2018-03-29

    Patients with stroke lesions offer a unique window into understanding human brain function. Studying stroke lesions poses several challenges due to the complexity of the lesion anatomy and the mechanisms causing local and remote disruptions on brain networks. In this prospective longitudinal study, we compare standard and advanced approaches to white matter lesion mapping applied to acute stroke patients with aphasia. Eighteen patients with acute left hemisphere stroke were recruited and scanned within two weeks from symptom onset. Aphasia assessment was performed at baseline and six-month follow-up. Structural and diffusion MRI contrasts indicated an area of maximum overlap in the anterior external/extreme capsule with diffusion images showing a larger overlap extending into posterior perisylvian regions. Predictors of recovery included damage to ipsilesional tracts (as shown by both structural and diffusion images) and contralesional tracts (as shown by diffusion images only). These findings indicate converging results from structural and diffusion lesions mapping analysis but clear differences between the two approaches in their ability to identify predictors of recovery. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Tomas Tranströmer's stroke of genius: language but no words.

    Science.gov (United States)

    Iniesta, Iván

    2013-01-01

    In 1990, the widely acclaimed Swedish poet Tomas Tranströmer lost his speech and the ability to use his right hand as a result of a stroke. As if anticipating his own fate, in 1974, he referred in his longest poem Baltics the story of the Russian composer Vissarion Shebalin who suffered the same symptoms as Tranströmer following a brain bleed: "Then, cerebral hemorrhage: paralysis on the right side with aphasia." An amateur pianist himself, Tranströmer carried on playing left-handed piano pieces after the stroke. In spite of a severe nonfluent dysphasia with dysgraphia, Tranströmer kept producing a poetic language of the highest caliber in accordance with his 1979 no less prophetic verse "language but no words." And through music and poetry, overcame the great communication barriers imposed by a large dominant hemispheric stroke. A nonprolific writer before the stroke, after it Tranströmer became disproportionately brief compared to his prestroke production, confining most of his poetry to the agrammatical and telegraphic haiku style. © 2013 Elsevier B.V. All rights reserved.

  6. Hypothalamic digoxin, hemispheric dominance, and neurobiology of love and affection.

    Science.gov (United States)

    Kurup, Ravi Kumar; Kurup, Parameswara Achutha

    2003-05-01

    The human hypothalamus produces an endogenous membrane Na+-K+ ATPase inhibitor, digoxin, which can regulate neuronal transmission. The digoxin status and neurotransmitter patterns were studied in individuals with a predilection to fall in love. It was also studied in individuals with differing hemispheric dominance to find out the role of cerebral dominance in this respect. In individuals with a predilection to fall in love there was decreased digoxin synthesis, increased membrane Na+-K+ ATPase activity, decreased tryptophan catabolites (serotonin, quinolinic acid, and nicotine), and increased tyrosine catabolites (dopamine, noradrenaline, and morphine). This pattern correlated with that obtained in left hemispheric chemical dominance. Hemispheric dominance and hypothalamic digoxin could regulate the predisposition to fall in love.

  7. Functional language shift to the right hemisphere in patients with language-eloquent brain tumors.

    Science.gov (United States)

    Krieg, Sandro M; Sollmann, Nico; Hauck, Theresa; Ille, Sebastian; Foerschler, Annette; Meyer, Bernhard; Ringel, Florian

    2013-01-01

    Language function is mainly located within the left hemisphere of the brain, especially in right-handed subjects. However, functional MRI (fMRI) has demonstrated changes of language organization in patients with left-sided perisylvian lesions to the right hemisphere. Because intracerebral lesions can impair fMRI, this study was designed to investigate human language plasticity with a virtual lesion model using repetitive navigated transcranial magnetic stimulation (rTMS). Fifteen patients with lesions of left-sided language-eloquent brain areas and 50 healthy and purely right-handed participants underwent bilateral rTMS language mapping via an object-naming task. All patients were proven to have left-sided language function during awake surgery. The rTMS-induced language errors were categorized into 6 different error types. The error ratio (induced errors/number of stimulations) was determined for each brain region on both hemispheres. A hemispheric dominance ratio was then defined for each region as the quotient of the error ratio (left/right) of the corresponding area of both hemispheres (ratio >1 = left dominant; ratio language-eloquent lesions showed a statistically significantly lower ratio than healthy participants concerning "all errors" and "all errors without hesitations", which indicates a higher participation of the right hemisphere in language function. Yet, there was no cortical region with pronounced difference in language dominance compared to the whole hemisphere. This is the first study that shows by means of an anatomically accurate virtual lesion model that a shift of language function to the non-dominant hemisphere can occur.

  8. Western Hemisphere Knowledge Partnerships

    Science.gov (United States)

    Malone, T. F.

    2001-05-01

    , and application of knowledge concerning the nature of -- and interaction among -- matter, living organisms, energy, information, and human behavior. This strategy calls for innovative partnerships among the physical, biological, health, and social sciences, engineering, and the humanities. New kinds of partnership must also be forged among academia, business and industry, governments, and nongovernmental organizations. Geophysicists can play an important role in these partnerships. A focus for these partnerships is to manage the individual economic productivity that drives both human development and global change. As world population approaches stability during the twenty-first century, individual economic productivity will be the critical link between the human and the natural systems on planet Earth. AGU is among a core group of individuals and institutions proposing Western Hemisphere Knowledge Partnerships (WHKP) to test the hypothesis that knowledge, broadly construed, is an important organizing principle in choosing a path into the future. The WHKP agenda includes: (1) life-long learning, (2) the health and resilience of natural ecosystems, (3) eco-efficiency in economic production and consumption, (4) extension of national income accounts, (5) environmentally benign sources of energy, (6) delivery of health care, (7) intellectual property rights, and (8) networks for action by local communities.Collaboratories and distance education technologies will be major tools. A panel of experts will explore this proposal.

  9. Writing induces a right hemisphere linguistic advantage in dysphonetic dyslexic children: implications for attention and capacity models of laterality.

    Science.gov (United States)

    Kershner, J; Henninger, P; Cooke, W

    1984-01-01

    An experiment demonstrated a complete hemispheric processing reversal in 10 male, dysphonetic dyslexic children that occurred during a dichotic listening test of their verbal working memory. Requiring a written response to dichotic digits produced a right hemisphere/left ear superiority in the dysphonetic dyslexics whereas normal subjects and other dyslexics maintained a left hemisphere/right ear advantage. This reversal was unaffected by changes in task difficulty. A second experiment assessed the influence on producing the reversal of concurrent manual interference with left hemisphere verbal processing (responding orally vs. manually) and selective right hemisphere priming (Forward Writing vs. Backward Writing). The dysphonetic children reverted to a strong left hemisphere superiority when recalling the dichotic digits orally. Backward writing produced no ear advantage in either direction. The findings suggest that dysphonetic dyslexia may be related to (1) left hemisphere processing demands that exceed capacity, (2) easily activated right hemisphere processing strategies and (3) failure to coordinate linguistic processing interhemispherically. The results supported a novel hybrid conceptualization of dyslexia consisting of a synthesis of selective activation, and dual processor-limited capacity, theories.

  10. Value of Combining Left Atrial Diameter and Amino-terminal Pro-brain Natriuretic Peptide to the CHA2DS2-VASc Score for Predicting Stroke and Death in Patients with Sick Sinus Syndrome after Pacemaker Implantation

    Directory of Open Access Journals (Sweden)

    Bin-Feng Mo

    2017-01-01

    Conclusions: CHA2DS2-VASc score is valuable for predicting stroke and death risk in patients with SSS after pacemaker implantation. The addition of LAD and NT-proBNP to the CHA2DS2-VASc score improved its predictive power for stroke and death, respectively, in this patient cohort. Future prospective studies are warranted to validate the benefit of adding LAD and NT-proBNP to the CHA2DS2-VASc score for predicting stroke and death risk in non-AF populations.

  11. Structural hemispheric asymmetries underlie verbal Stroop performance.

    Science.gov (United States)

    Vallesi, Antonino; Mazzonetto, Ilaria; Ambrosini, Ettore; Babcock, Laura; Capizzi, Mariagrazia; Arbula, Sandra; Tarantino, Vincenza; Semenza, Carlo; Bertoldo, Alessandra

    2017-09-29

    Performance on tasks involving cognitive control such as the Stroop task is often associated with left lateralized brain activations. Based on this neuro-functional evidence, we tested whether leftward structural grey matter asymmetries would also predict inter-individual differences in combatting Stroop interference. To check for the specificity of the results, both a verbal Stroop task and a spatial one were administered to a total of 111 healthy young individuals, for whom T1-weighted magnetic resonance imaging (MRI) images were also acquired. Surface thickness and area estimations were calculated using FreeSurfer. Participants' hemispheres were registered to a symmetric template and Laterality Indices (LI) for the surface thickness and for the area at each vertex in each participant were computed. The correlation of these surface LI measures with the verbal and spatial Stroop effects (incongruent-congruent difference in trial performance) was assessed at each vertex by means of general linear models at the whole-brain level. We found a significant correlation between performance and surface area LI in an inferior posterior temporal cluster (overlapping with the so-called visual word form area, VWFA), with a more left-lateralized area in this region associated with a smaller Stroop effect only in the verbal task. These results point to an involvement of the VWFA for higher-level processes based on word reading, including the suppression of this process when required by the task, and could be interpreted in the context of cross-hemispheric rivalry. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Motor and premotor cortices in subcortical stroke: proton magnetic resonance spectroscopy measures and arm motor impairment.

    Science.gov (United States)

    Craciunas, Sorin C; Brooks, William M; Nudo, Randolph J; Popescu, Elena A; Choi, In-Young; Lee, Phil; Yeh, Hung-Wen; Savage, Cary R; Cirstea, Carmen M

    2013-06-01

    Although functional imaging and neurophysiological approaches reveal alterations in motor and premotor areas after stroke, insights into neurobiological events underlying these alterations are limited in human studies. We tested whether cerebral metabolites related to neuronal and glial compartments are altered in the hand representation in bilateral motor and premotor areas and correlated with distal and proximal arm motor impairment in hemiparetic persons. In 20 participants at >6 months postonset of a subcortical ischemic stroke and 16 age- and sex-matched healthy controls, the concentrations of N-acetylaspartate and myo-inositol were quantified by proton magnetic resonance spectroscopy. Regions of interest identified by functional magnetic resonance imaging included primary (M1), dorsal premotor (PMd), and supplementary (SMA) motor areas. Relationships between metabolite concentrations and distal (hand) and proximal (shoulder/elbow) motor impairment using Fugl-Meyer Upper Extremity (FMUE) subscores were explored. N-Acetylaspartate was lower in M1 (P = .04) and SMA (P = .004) and myo-inositol was higher in M1 (P = .003) and PMd (P = .03) in the injured (ipsilesional) hemisphere after stroke compared with the left hemisphere in controls. N-Acetylaspartate in ipsilesional M1 was positively correlated with hand FMUE subscores (P = .04). Significant positive correlations were also found between N-acetylaspartate in ipsilesional M1, PMd, and SMA and in contralesional M1 and shoulder/elbow FMUE subscores (P = .02, .01, .02, and .02, respectively). Our preliminary results demonstrated that proton magnetic resonance spectroscopy is a sensitive method to quantify relevant neuronal changes in spared motor cortex after stroke and consequently increase our knowledge of the factors leading from these changes to arm motor impairment.

  13. Ischemic Stroke

    Science.gov (United States)

    ... Workplace Giving Fundraise Planned Giving Corporate Giving Cause Marketing Join your team, your way! The Stroke Challenge ... Your Technology Guide High Blood Pressure and Stroke Importance of Physical Activity See More Multimedia Las minorías ...

  14. Stroke - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100218.htm Stroke - series—Part 1 To use the sharing features ... M. Editorial team. Related MedlinePlus Health Topics Ischemic Stroke A.D.A.M., Inc. is accredited by ...

  15. Reduced contralateral hemispheric flow measured by SPECT in cerebellar lesions

    DEFF Research Database (Denmark)

    Sönmezoğlu, K; Sperling, B; Henriksen, T

    1993-01-01

    Four patients with clinical signs of cerebellar stroke were studied twice by SPECT using 99mTc-HMPAO as a tracer for cerebral blood flow (CBF). When first scanned 6 to 22 days after onset, all had a region of very low CBF in the symptomatic cerebellar hemisphere, and a mild to moderate CBF...... reduction (average 10%) in contralateral hemispheric cortex. In all four cases clinical signs of unilateral cerebellar dysfunction were still present when rescanned 1 to 4 months later and the relative CBF decrease in the contralateral cortex of the forebrain also remained. The basal ganglia contralateral...... to the cerebellar lesion CBF showed variable alterations. A relative CBF decrease was seen in upper part of basal ganglia in all four cases, but it was not a constant phenomenon. A relative CBF increase in both early and late SPECT scans was seen at low levels of neostriatum in two cases. The remote CBF changes...

  16. Language localization in cases of left temporal lobe arachnoid cyst : Evidence against interhemispheric reorganization

    NARCIS (Netherlands)

    Stowe, LA; Go, KG; Pruim, J; den Dunnen, W; Meiners, LC; Paans, AMJ

    2000-01-01

    We investigated whether left-hemisphere arachnoid cysts lead to reorganization of the language function using PET. A group analysis demonstrated that patients showed no more right-hemisphere activation than a matched control group. Several patients had clear language localizations in the left

  17. Bidirectional connectivity between hemispheres occurs at multiple levels in language processing but depends on sex.

    Science.gov (United States)

    Bitan, Tali; Lifshitz, Adi; Breznitz, Zvia; Booth, James R

    2010-09-01

    Our aim was to determine the direction of interhemispheric communication in a phonological task in regions involved in different levels of processing. Effective connectivity analysis was conducted on functional magnetic resonance imaging data from 39 children (ages 9-15 years) performing rhyming judgment on spoken words. The results show interaction between hemispheres at multiple levels. First, there is unidirectional transfer of information from right to left at the sensory level of primary auditory cortex. Second, bidirectional connections between superior temporal gyri (STGs) suggest a reciprocal cooperation between hemispheres at the level of phonological and prosodic processing. Third, a direct connection from right STG to left inferior frontal gyrus suggest that information processed in the right STG is integrated into the final stages of phonological segmentation required for the rhyming decision. Intrahemispheric connectivity from primary auditory cortex to STG was stronger in the left compared to the right hemisphere. These results support a model of cooperation between hemispheres, with asymmetric interhemispheric and intrahemispheric connectivity consistent with the left hemisphere specialization for phonological processing. Finally, we found greater interhemispheric connectivity in girls compared to boys, consistent with the hypothesis of a more bilateral representation of language in females than males. However, interhemispheric communication was associated with slow performance and low verbal intelligent quotient within girls. We suggest that females may have the potential for greater interhemispheric cooperation, which may be an advantage in certain tasks. However, in other tasks too much communication between hemispheres may interfere with task performance.

  18. Cryptogenic Stroke

    Directory of Open Access Journals (Sweden)

    Mohammad Saadatnia

    2017-02-01

    Full Text Available Cryptogenic stroke is defined as brain infarction that is not attributable to a source of definite embolism, large artery atherosclerosis, or small artery disease despite a thorough vascular, cardiac, and serologic evaluation. Despite many advances in our understanding of ischemic stroke, cryptogenic strokes remain a diagnostic and therapeutic challenge. The pathophysiology of cryptogenic stroke is likely various. Probable mechanisms include cardiac embolism secondary to occult paroxysmal atrial fibrillation, aortic atheromatous disease or other cardiac sources, paradoxical embolism from atrial septal abnormalities such as patent foramen ovale, hypercoagulable states, and preclinical or subclinical cerebrovascular disease.  Cryptogenic stroke is one-fourth among cerebral infarction, but most of them could be ascribed to embolic stroke. A significant proportion of cryptogenic strokes adhere to embolic infarct topography on brain imaging and improvement in our ability to detect paroxysmal atrial fibrillation in patients with cryptogenic stroke has strengthened the idea that these strokes are embolic in nature. a significant proportion of cryptogenic strokes adhere to embolic infarct topography on brain imaging.embolic stroke of undetermined sources(ESUS was planned for unifying embolic stroke of undetermined source.  The etiologies underlying ESUS included minor-risk potential cardioembolic sources, covert paroxysmal atrial fibrillation, cancer-associated coagulopathy and embolism, arteriogenic emboli, and paroxysmal embolism. Extensive evaluation including transesophageal echocardiography and cardiac monitoring for long time could identify the etiology of these patients. Therefore cryptogenic stroke is a diagnosis of exclusion. Compared with other stroke subtypes, cryptogenic stroke tends to have a better prognosis and lower long-term risk of recurrence.

  19. The Effects of Multiple Script Priming on Word Recognition by the Two Cerebral Hemispheres: Implications for Discourse Processing

    Science.gov (United States)

    Faust, Miriam; Barak, Ofra; Chiarello, Christine

    2006-01-01

    The present study examined left (LH) and right (RH) hemisphere involvement in discourse processing by testing the ability of each hemisphere to use world knowledge in the form of script contexts for word recognition. Participants made lexical decisions to laterally presented target words preceded by centrally presented script primes (four…

  20. Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with a right hemispheric lesion.

    Science.gov (United States)

    Tanaka, Satoshi; Seki, Keiko; Hanakawa, Takashi; Harada, Madoka; Sugawara, Sho K; Sadato, Norihiro; Watanabe, Katsumi; Honda, Manabu

    2012-01-01

    The abacus, a traditional physical calculation device, is still widely used in Asian countries. Previous behavioral work has shown that skilled abacus users perform rapid and precise mental arithmetic by manipulating a mental representation of an abacus, which is based on visual imagery. However, its neurophysiological basis remains unclear. Here, we report the case of a patient who was a good abacus user, but transiently lost her "mental abacus" and superior arithmetic performance after a stroke owing to a right hemispheric lesion including the dorsal premotor cortex (PMd) and inferior parietal lobule (IPL). Functional magnetic resonance imaging experiments were conducted 6 and 13 months after her stroke. In the mental calculation task, her brain activity was shifted from the language-related areas, including Broca's area and the left dorsolateral prefrontal and IPLs, to the visuospatial-related brain areas including the left superior parietal lobule (SPL), according to the recovery of her arithmetic abilities. In the digit memory task, activities in the bilateral SPL, and right visual association cortex were also observed after recovery. The shift of brain activities was consistent with her subjective report that she was able to shift the calculation strategy from linguistic to visuospatial as her mental abacus became stable again. In a behavioral experiment using an interference paradigm, a visual presentation of an abacus picture, but not a human face picture, interfered with the performance of her digit memory, confirming her use of the mental abacus after recovery. This is the first case report on the impairment of the mental abacus by a brain lesion and on recovery-related brain activity. We named this rare case "abacus-based acalculia." Together with previous neuroimaging studies, the present result suggests an important role for the PMd and parietal cortex in the superior arithmetic ability of abacus users.

  1. Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with the right hemispheric lesion

    Directory of Open Access Journals (Sweden)

    Satoshi eTanaka

    2012-08-01

    Full Text Available The abacus, a traditional physical calculation device, is still widely used in Asian countries. Previous behavioral work has shown that skilled abacus users perform rapid and precise mental arithmetic by manipulating a mental representation of an abacus, which is based on visual imagery. However, its neurophysiological basis remains unclear. Here, we report the case of a patient who was a good abacus user, but transiently lost her mental abacus and superior arithmetic performance after a stroke owing to a right hemispheric lesion including the dorsal premotor cortex and inferior parietal lobule.Functional magnetic resonance imaging experiments were conducted 6 and 13 months after her stroke. In the mental calculation task, her brain activity was shifted from the language-related areas, including Broca’s area and the left dorsolateral prefrontal and inferior parietal lobules, to the visuospatial-related brain areas including the left superior parietal lobule, according to the recovery of her arithmetic abilities. In the digit memory task, activities in the bilateral superior parietal lobule and right visual association cortex were also observed after recovery. The shift of brain activities was consistent with her subjective report that she was able to shift the calculation strategy from linguistic to visuospatial as her mental abacus became stable again. In a behavioral experiment using an interference paradigm, a visual presentation of an abacus picture, but not a human face picture, interfered with the performance of her digit memory, confirming her use of the mental abacus after recovery.This is the first case report on the impairment of the mental abacus by a brain lesion and on recovery-related brain activity. We named this rare case abacus-based acalculia. Together with previous neuroimaging studies, the present result suggests an important role for the dorsal premotor cortex and parietal cortex in the superior arithmetic ability of

  2. Patterns of Reading Performance in Acute Stroke: A Descriptive Analysis

    Directory of Open Access Journals (Sweden)

    Lauren L. Cloutman

    2010-01-01

    Full Text Available One of the main sources of information regarding the underlying processes involved in both normal and impaired reading has been the study of reading deficits that occur as a result of brain damage. However, patterns of reading deficits found acutely after brain injury have been little explored. The observed patterns of performance in chronic stroke patients might reflect reorganization of the cognitive processes underlying reading or development of compensatory strategies that are not normally used to read. Method: 112 acute left hemisphere stroke patients were administered a task of oral reading of words and pseudowords within 1–2 days of hospital admission; performance was examined for error rate and type, and compared to that on tasks involving visual lexical decision, visual/auditory comprehension, and naming. Results: Several distinct patterns of performance were identified. Although similarities were found between the patterns of reading performance observed acutely and the classical acquired dyslexias generally identified more chronically, some notable differences were observed. Of interest was the finding that no patient produced any pure semantic errors in reading, despite finding such errors in comprehension and naming.

  3. Early Seizures After Stroke: Neurology Intensive Care Unit Experience

    Directory of Open Access Journals (Sweden)

    Şadiye Gümüşyayla

    2018-03-01

    Full Text Available Objective: The aim of this study was to investigate the frequency of early seizures, the affecting factors, and the prognostic effect of seizures in patients with acute ischemic stroke (AIS, intracerebral hemorrhage (ICH, and sinus venous thrombosis (SVT examined in the intensive care unit (ICU. Materials and Methods: In the neurology ICU, the records of patients followed up with AIS, ICH, and SVT within a defined time period were retrospectively examined. Results: Early seizures occurred in 48 out of 199 patients who were followed up with AIS, ICH, and SVT in the neurology ICU within the specified time period. The frequency of having early seizures was found to be higher in patients with left hemisphere lesions, cortical lesions, and those with AIS with hemorrhagic transformation. Lesion volume was found to be higher in patients with AIS who had early seizures compared with those who had AIS without seizures. Early seizures were observed in all patients with SVT who were followed up in the ICU. Conclusion: Early seizures are a common complication in patients with stroke followed up in neurology ICUs. Determination of effective factors in early seizures is important for its early diagnosis and treatment

  4. Hemispheric asymmetries in memory processes as measured in a false recognition paradigm.

    Science.gov (United States)

    Westerberg, Carmen E; Marsolek, Chad J

    2003-01-01

    Although memory differs in important ways between the left and right cerebral hemispheres, the nature of these differences remains controversial. We examined this issue in two experiments using a false memory paradigm that allowed novel tests of two theories that have not been assessed in a common paradigm previously. Lists of semantically related words (e.g., bed, rest, wake...), all highly associated to one "critical" word (e.g., sleep), were presented auditorily during a study phase. Memory for both the related words and the critical words was measured in a subsequent old/new recognition test using divided-visual-field word presentations. The most important results were that the ability to correctly reject previously unpresented words was greater when test items were presented to the right visual field/left hemisphere (RVF/LH) than to the left visual field/right hemisphere (LVF/RH) and that participants were more confident in correctly rejecting unpresented words when test items were presented to the RVF/LH than to the LVF/RH. Results were in line with the theory that associative activation of semantic information is restricted in the left hemisphere but diffuse in the right; however, these results contrasted with the theory that memory traces are interpretive in the left hemisphere but veridical in the right. A potential resolution to the seemingly contradictory theories of asymmetries in memory processing is briefly discussed.

  5. [Sex differences in hemispheric interference interaction during the memorizing of speech information].

    Science.gov (United States)

    Vol'f, N V

    1998-01-01

    Young men and women were monaurally and dichotically presented with 10-word lists which had to be afterwards reproduced in a written form. In dichotic pairs the signals were presented either synchronously or with time leads/lags in 50 ms between the ears. For each subject the interference effect was calculated of the right hemisphere to the left one and on the contrary. This index was taken as a measure of inhibitory interaction between the hemispheres. Lateral differences in hemispheric interference were well pronounced in men and absent in women. In women the interference effects on the first halves of the lists were stronger than in men and more pronounced than the effects on the second halves of the lists. The results are in agreement with the ideas about functional dissimilarity of processes underlying speech functions in the left and right brain hemispheres in men and women.

  6. Processing of unconventional stimuli requires the recruitment of the non-specialized hemisphere.

    Science.gov (United States)

    Kenett, Yoed N; Anaki, David; Faust, Miriam

    2015-01-01

    In the present study we investigate hemispheric processing of conventional and unconventional visual stimuli in the context of visual and verbal creative ability. In Experiment 1, we studied two unconventional visual recognition tasks-Mooney face and objects' silhouette recognition-and found a significant relationship between measures of verbal creativity and unconventional face recognition. In Experiment 2 we used the split visual field (SVF) paradigm to investigate hemispheric processing of conventional and unconventional faces and its relation to verbal and visual characteristics of creativity. Results showed that while conventional faces were better processed by the specialized right hemisphere (RH), unconventional faces were better processed by the non-specialized left hemisphere (LH). In addition, only unconventional face processing by the non-specialized LH was related to verbal and visual measures of creative ability. Our findings demonstrate the role of the non-specialized hemisphere in processing unconventional stimuli and how it relates to creativity.

  7. Left neglected, but only in far space: Spatial biases in healthy participants revealed in a visually-guided grasping task

    Directory of Open Access Journals (Sweden)

    Natalie ede Bruin

    2014-01-01

    Full Text Available Hemispatial neglect is a common outcome of stroke that is characterised by the inability to orient towards, and attend to stimuli in contralesional space. It is established that hemispatial neglect has a perceptual component, however, the presence and severity of motor impairments is controversial. Establishing the nature of space use and spatial biases during visually-guided actions amongst healthy individuals is critical to understanding the presence of visuomotor deficits in patients with neglect. Accordingly, three experiments were conducted to investigate the effect of object spatial location on patterns of grasping. Experiment 1 required right-handed participants to reach and grasp for blocks in order to construct 3D models. The blocks were scattered on a tabletop divided into equal size quadrants: left near, left far, right near, and right far. Identical sets of building blocks were available in each quadrant. Space use was dynamic, with participants initially grasping blocks from right near space and tending to ‘neglect’ left far space until the final stages of the task. Experiment 2 repeated the protocol with left-handed participants. Remarkably, left-handed participants displayed a similar pattern of space use to right-handed participants. In Experiment 3 eye movements were examined to investigate whether ‘neglect’ for grasping in left far reachable space had its origins in attentional biases. It was found that patterns of eye movements mirrored patterns of reach-to-grasp movements. We conclude that there are spatial biases during visually-guided grasping, specifically, a tendency to neglect left far reachable space, and that this ‘neglect’ is attentional in origin. The results raise the possibility that visuomotor impairments reported among patients with right hemisphere lesions when working in contralesional space may result in part from this inherent tendency to ‘neglect’ left far space irrespective of the presence

  8. Auditory and cognitive deficits associated with acquired amusia after stroke: a magnetoencephalography and neuropsychological follow-up study.

    Directory of Open Access Journals (Sweden)

    Teppo Särkämö

    2010-12-01

    Full Text Available Acquired amusia is a common disorder after damage to the middle cerebral artery (MCA territory. However, its neurocognitive mechanisms, especially the relative contribution of perceptual and cognitive factors, are still unclear. We studied cognitive and auditory processing in the amusic brain by performing neuropsychological testing as well as magnetoencephalography (MEG measurements of frequency and duration discrimination using magnetic mismatch negativity (MMNm recordings. Fifty-three patients with a left (n = 24 or right (n = 29 hemisphere MCA stroke (MRI verified were investigated 1 week, 3 months, and 6 months after the stroke. Amusia was evaluated using the Montreal Battery of Evaluation of Amusia (MBEA. We found that amusia caused by right hemisphere damage (RHD, especially to temporal and frontal areas, was more severe than amusia caused by left hemisphere damage (LHD. Furthermore, the severity of amusia was found to correlate with weaker frequency MMNm responses only in amusic RHD patients. Additionally, within the RHD subgroup, the amusic patients who had damage to the auditory cortex (AC showed worse recovery on the MBEA as well as weaker MMNm responses throughout the 6-month follow-up than the non-amusic patients or the amusic patients without AC damage. Furthermore, the amusic patients both with and without AC damage performed worse than the non-amusic patients on tests of working memory, attention, and cognitive flexibility. These findings suggest domain-general cognitive deficits to be the primary mechanism underlying amusia without AC damage whereas amusia with AC damage is associated with both auditory and cognitive deficits.

  9. Auditory and cognitive deficits associated with acquired amusia after stroke: a magnetoencephalography and neuropsychological follow-up study.

    Science.gov (United States)

    Särkämö, Teppo; Tervaniemi, Mari; Soinila, Seppo; Autti, Taina; Silvennoinen, Heli M; Laine, Matti; Hietanen, Marja; Pihko, Elina

    2010-12-02

    Acquired amusia is a common disorder after damage to the middle cerebral artery (MCA) territory. However, its neurocognitive mechanisms, especially the relative contribution of perceptual and cognitive factors, are still unclear. We studied cognitive and auditory processing in the amusic brain by performing neuropsychological testing as well as magnetoencephalography (MEG) measurements of frequency and duration discrimination using magnetic mismatch negativity (MMNm) recordings. Fifty-three patients with a left (n = 24) or right (n = 29) hemisphere MCA stroke (MRI verified) were investigated 1 week, 3 months, and 6 months after the stroke. Amusia was evaluated using the Montreal Battery of Evaluation of Amusia (MBEA). We found that amusia caused by right hemisphere damage (RHD), especially to temporal and frontal areas, was more severe than amusia caused by left hemisphere damage (LHD). Furthermore, the severity of amusia was found to correlate with weaker frequency MMNm responses only in amusic RHD patients. Additionally, within the RHD subgroup, the amusic patients who had damage to the auditory cortex (AC) showed worse recovery on the MBEA as well as weaker MMNm responses throughout the 6-month follow-up than the non-amusic patients or the amusic patients without AC damage. Furthermore, the amusic patients both with and without AC damage performed worse than the non-amusic patients on tests of working memory, attention, and cognitive flexibility. These findings suggest domain-general cognitive deficits to be the primary mechanism underlying amusia without AC damage whereas amusia with AC damage is associated with both auditory and cognitive deficits.

  10. The measurement of blood flow in the cerebral hemispheres using a radioactive tracer

    International Nuclear Information System (INIS)

    Calegaro, J.U.M.; Reis, J.M.M. dos; Lopes, P.G.; Ribeiro, J.I.C.; Mansano, A.

    1978-01-01

    The modified Olendorf technique to measure the passage of a non-diffusible radioactive tracer through the cerebral hemispheres is described. The results given as brain transit time presents the following normal values: right hemisphere = 11,0 +- 2,8s (s.d.); left hemisphere = 11,0 +- 2,9s (s.d.). The equipment used is a two scintillation detectors sistem (with flat field collimation) with simultaneous chard recorder. The values obtained are taken as cerebral blood flow index. From 20 patients studied, 12 have obstructive carotid [pt

  11. Models of hemispheric specialization in facial emotion perception--a reevaluation.

    Science.gov (United States)

    Najt, Pablo; Bayer, Ulrike; Hausmann, Markus

    2013-02-01

    A considerable amount of research on functional cerebral asymmetries (FCAs) for facial emotion perception has shown conflicting support for three competing models: (i) the Right Hemisphere Hypothesis, (ii) the Valence-Specific Hypothesis, and (iii) the Approach/Withdrawal model. However, the majority of studies evaluating the Right Hemisphere or the Valence-Specific Hypotheses are rather limited by the small number of emotional expressions used. In addition, it is difficult to evaluate the Approach/Withdrawal Hypothesis due to insufficient data on anger and FCAs. The aim of the present study was (a) to review visual half field (VHF) studies of hemispheric specialization in facial emotion perception and (b) to reevaluate empirical evidence with respect to all three partly conflicting hypotheses. Results from the present study revealed a left visual field (LVF)/right hemisphere advantage for the perception of angry, fearful, and sad facial expressions and a right visual field (RVF)/left hemisphere advantage for the perception of happy expressions. Thus, FCAs for the perception of specific facial emotions do not fully support the Right Hemisphere Hypothesis, the Valence-Specific Hypothesis, or the Approach/Withdrawal model. A systematic literature review, together with the results of the present study, indicate a consistent LVF/right hemisphere advantage only for a subset of negative emotions including anger, fear and sadness, rather suggesting a "negative (only) valence model." PsycINFO Database Record (c) 2013 APA, all rights reserved.

  12. The time window for successful right-hemispheric language reorganization in children.

    Science.gov (United States)

    Lidzba, Karen; Küpper, Hanna; Kluger, Gerhard; Staudt, Martin

    2017-09-01

    To identify, in a retrospective, observational study, the time window during which successful right-hemispheric language reorganization is possible after left-hemispheric brain damage. 25 patients (10 females; age 6-41 years; ≥12 months after insult; age at insult 0;3-15;11 years) with acute, language-relevant left-hemispheric insults acquired during childhood and adolescence completed questionnaires for self-assessment of language problems. 12 patients of those reporting no (n = 8) or only moderate (n = 4) language problems participated in language fMRI. Language outcome of lesions occurring before 5 years of age (n = 7) was always favorable, and language was right-lateralized (2 patients: age at lesion reorganization (fMRI available in 4). The combination of normal language outcome and right-hemispheric language reorganization after a left-hemispheric lesion sustained after the neonatal period is extremely rare. Functionally sufficient right-hemispheric language was documented in only two patients with lesions acquired before two years of age. Copyright © 2017 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  13. Effect of subtypes of neglect on functional outcome in stroke patients.

    Science.gov (United States)

    Spaccavento, Simona; Cellamare, Fara; Falcone, Rosanna; Loverre, Anna; Nardulli, Roberto

    2017-11-01

    Because of the loss of autonomy in daily-life activities, spatial neglect after stroke is one of the main causes of disability. According to the spatial domains, neglect can be divided into personal (body), peripersonal (reaching) and extrapersonal (far) space. We evaluated the effect of these subtypes of neglect on functional outcome of rehabilitation in stroke patients. A total of 1350 stroke patients were consecutively admitted into our neurorehabilitation unit from 2002 to 2016. We analyzed data for patients with a first ischemic or hemorrhagic right-hemispheric stroke in this observational retrospective study. The presence of neglect was evaluated by using structured tests for specific spatial domains. Patients underwent individual physical and occupational therapy, and those with neglect received specific therapy for 8 consecutive weeks consisting of visual scanning, reading and copying, copying line drawings on a dot matrix and describing scenes. The Functional Independence Measure (FIM) instrument was administered at both admission and discharge to assess functional autonomy. Rehabilitation effectiveness for FIM (percentage of potential improvement achieved) was calculated. Multiple regression analyses were performed. Among 359 patients with right-brain damage, 130 showed left neglect, or unilateral spatial neglect (USN), and 229 only left hemiparesis, without neglect. Overall, 90 patients (69%) with USN showed peripersonal neglect, 89 (68%) extrapersonal neglect and 60 (46%) personal neglect. Functional motor and cognitive impairment was greater with than without USN as measured by FIM at admission and discharge and the rehabilitation hospital stay was longer. USN affected functional status at admission and rehabilitation effectiveness for FIM. Extrapersonal and peripersonal neglect significantly affected both function at admission and effectiveness. Our data confirm the negative prognostic effect of neglect on functional outcome in a large sample. We also

  14. Hemispheric Specialization and Functional Plasticity during Development.

    Science.gov (United States)

    Levine, Susan Cohen

    1983-01-01

    Reviews literature on hemispheric specialization. Argues that foundations of hemispheric specialization are present very early in life and that children's greater ability to recover functions following brain injury suggests developmental changes in brain organization. (CMG)

  15. Reduced contralateral hemispheric flow measured by SPECT in cerebellar lesions

    International Nuclear Information System (INIS)

    Soenmezoglu, K.; Sperling, B.; Lassen, N.A.; Henriksen, T.; Tfelt-Hansen, P.

    1993-01-01

    Four patients with clinical signs of cerebellar stroke were studied twice by SPECT using 99m Tc-HMPAO as a tracer for cerebral blood flow (CBF). When first scanned 6 to 22 days after onset, all had a region of very low CBF in the symptomatic cerebellar hemisphere, and a mild to moderate CBF reduction (average 10%) in contralateral hemispheric cortex. In all four cases clinical signs of unilateral cerebellar dysfunction were still present when rescanned 1 to 4 months later and the relative CBF decrease in the contralateral cortex of the forebrain also remained. The basal ganglia contralateral to the cerebellar lesion CBF showed variable alterations. A relative CBF decrease was seen in upper part of basal ganglia in all four cases, but it was not a constant phenomenon. A relative CBF increase in both early and late SPECT scans was seen at low levels of neostriatum in two cases. The remote CBF changes in cerebellar stroke seen in the forebrain are probably caused by reduced or abolished cerebellar output. The term ''Crossed Cerebral Diaschisis'' may be used to describe these CBF changes that would appear to reflect both decreased and increased neuronal activity. (au)

  16. Hemispheric ultra-wideband antenna.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2006-04-01

    This report begins with a review of reduced size ultra-wideband (UWB) antennas and the peculiar problems that arise when building a UWB antenna. It then gives a description of a new type of UWB antenna that resolves these problems. This antenna, dubbed the hemispheric conical antenna, is similar to a conventional conical antenna in that it uses the same inverted conical conductor over a ground plane, but it also uses a hemispheric dielectric fill in between the conductive cone and the ground plane. The dielectric material creates a fundamentally new antenna which is reduced in size and much more rugged than a standard UWB conical antenna. The creation of finite-difference time domain (FDTD) software tools in spherical coordinates, as described in SAND2004-6577, enabled this technological advance.

  17. Recovering after stroke

    Science.gov (United States)

    Stroke rehabilitation; Cerebrovascular accident - rehabilitation; Recovery from stroke; Stroke - recovery; CVA - recovery ... LIVE AFTER A STROKE Most people will need stroke rehabilitation (rehab) to help them recover after they leave ...

  18. Real-time monitoring of ischemic and contralateral brain pO2 during stroke by variable length multisite resonators.

    Science.gov (United States)

    Hou, Huagang; Li, Hongbin; Dong, Ruhong; Khan, Nadeem; Swartz, Harold

    2014-06-01

    Electron paramagnetic resonance (EPR) oximetry using variable length multi-probe implantable resonator (IR), was used to investigate the temporal changes in the ischemic and contralateral brain pO2 during stroke in rats. The EPR signal to noise ratio (S/N) of the IR with four sensor loops at a depth of up to 11 mm were compared with direct implantation of lithium phthalocyanine (LiPc, oximetry probe) deposits in vitro. These IRs were used to follow the temporal changes in pO2 at two sites in each hemisphere during ischemia induced by left middle cerebral artery occlusion (MCAO) in rats breathing 30% O2 or 100% O2. The S/N ratios of the IRs were significantly greater than the LiPc deposits. A similar pO2 at two sites in each hemisphere prior to the onset of ischemia was observed in rats breathing 30% O2. However, a significant decline in the pO2 of the left cortex and striatum occurred during ischemia, but no change in the pO2 of the contralateral brain was observed. A significant increase in the pO2 of only the contralateral non-ischemic brain was observed in the rats breathing 100% O2. No significant difference in the infarct volume was evident between the animals breathing 30% O2 or 100% O2 during ischemia. EPR oximetry with IRs can repeatedly assess temporal changes in the brain pO2 at four sites simultaneously during stroke. This oximetry approach can be used to test and develop interventions to rescue ischemic tissue by modulating cerebral pO2 during stroke. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. No effects of anodal transcranial direct stimulation on language abilities in early rehabilitation of post-stroke aphasic patients.

    Science.gov (United States)

    Polanowska, K E; Leśniak, M; Seniów, J B; Członkowska, A

    2013-01-01

    Recent research suggests that an increased level of stroke-affected left hemisphere cortical (especially frontal) excitability is associated with better language improvement in aphasic patients. Anodal transcranial direct current stimulation (A-tDCS), increasing cortical activity, may facilitate perilesional left hemisphere recruitment to subserve language processing and enhance effects of behavioural therapy. The aim of the study (randomized, double-blind, sham-controlled) was to evaluate the effectiveness of repeated A-tDCS over Broca area as a strategy to enhance aphasia recovery during early post-stroke rehabilitation. Thirty-seven participants with moderate or severe aphasia were randomized to receive 15 consecutive daily sessions of A-tDCS (1 mA, 10 min; experimental group, n = 18) or sham stimulation (1 mA, 25 s; control group, n = 19) followed by language therapy. Effects of tDCS were assessed using the Boston Diagnostic Aphasia Examination, performed before and after the rehabilitation, and three months later. The results did not confirm a positive impact of repeated A-tDCS, preceding language therapy, on language abilities in our patients. Although both groups improved after the therapy, there were no statistically significant differences between groups in either short-term or long-term tDCS effects. Effect sizes for the experimental group, at post-treatment and the 3-month follow-up, were slightly higher than in controls but insufficient to infer any beneficial influence of the applied intervention. The findings do not support A-tDCS functional benefits during early rehabilitation of post-stroke aphasia. Further research is needed to explore the effectiveness of this kind of neuromodulation.

  20. Hemispheric Laterality in Music and Math

    Science.gov (United States)

    Szirony, Gary Michael; Burgin, John S.; Pearson, L. Carolyn

    2008-01-01

    Hemispheric laterality may be a useful concept in teaching, learning, training, and in understanding more about human development. To address this issue, a measure of hemispheric laterality was compared to musical and mathematical ability. The Human Information Processing Survey (HIPS) instrument, designed to measure hemispheric laterality, was…

  1. Pre-stroke apathy symptoms are associated with an increased risk of delirium in stroke patients.

    Science.gov (United States)

    Klimiec, Elzbieta; Kowalska, Katarzyna; Pasinska, Paulina; Klimkowicz-Mrowiec, Aleksandra; Szyper, Aleksandra; Pera, Joanna; Slowik, Agnieszka; Dziedzic, Tomasz

    2017-08-09

    Neuropsychiatric symptoms can be interrelated to delirium. We aimed to investigate an association between pre-stroke neuropsychiatric symptoms and the risk of delirium in stroke patients. We included 606 patients (median age: 73, 53% female) with stroke or transient ischemic attack admitted within 48 hours from symptoms onset. We assessed delirium on a daily basis during the first 7 days of hospitalization. To make diagnosis of delirium we used DSM-5 criteria. We used Neuropsychiatric Inventory to assess neuropsychiatric symptoms occurring within 4 weeks prior to stroke. We diagnosed delirium in 28.2% of patients. On univariate analysis, higher score of pre-stroke depression (OR: 1.58, 95% CI: 1.04-2.40, P = 0.03), apathy (OR: 2.23, 95% CI: 1.44-3.45, P delirium. On multivariate analysis adjusted for age, atrial fibrillation, diabetes mellitus, stroke severity, right hemisphere lesion, pre-stroke cognitive decline, pre-stroke disability and infections, higher apathy score (OR: 2.03, 95% CI: 1.17-3.50, P = 0.01), but no other neuropsychiatric symptoms, remained independent predictor of delirium. We conclude that pre-stroke apathy symptoms are associated with increased risk of delirium in stroke patients.

  2. Preservation of structural brain network hubs is associated with less severe post-stroke aphasia.

    Science.gov (United States)

    Gleichgerrcht, Ezequiel; Kocher, Madison; Nesland, Travis; Rorden, Chris; Fridriksson, Julius; Bonilha, Leonardo

    2015-01-01

    Post-stroke aphasia is typically associated with ischemic damage to cortical areas or with loss of connectivity among spared brain regions. It remains unclear whether the participation of spared brain regions as networks hubs affects the severity of aphasia. We evaluated language performance and magnetic resonance imaging from 44 participants with chronic aphasia post-stroke. The individual structural brain connectomes were constructed from diffusion tensor. Hub regions were defined in accordance with the rich club classification and studied in relation with language performance. Number of remaining left hemisphere rich club nodes was associated with aphasia, including comprehension, repetition and naming sub-scores. Importantly, among participants with relative preservation of regions of interest for language, aphasia severity was lessened if the region was not only spared, but also participated in the remaining network as a rich club node: Brodmann area (BA) 44/45 - repetition (p = 0.009), BA 39 - repetition (p = 0.045) and naming (p hubs is directly associated with aphasia severity after stroke.

  3. Differences in the role of black race and stroke risk factors for first vs recurrent stroke

    Science.gov (United States)

    Kissela, Brett M.; Kleindorfer, Dawn O.; McClure, Leslie A.; Soliman, Elsayed Z.; Judd, Suzanne E.; Rhodes, J. David; Cushman, Mary; Moy, Claudia S.; Sands, Kara A.; Howard, Virginia J.

    2016-01-01

    Objectives: To assess whether black race and other cerebrovascular risk factors have a differential effect on first vs recurrent stroke events. Methods: Estimate the differences in the magnitude of the association of demographic (age, back race, sex) or stroke risk factors (hypertension, diabetes, cigarette smoking, atrial fibrillation, left ventricular hypertrophy, or heart disease) for first vs recurrent stroke from a longitudinal cohort study of 29,682 black or white participants aged 45 years and older. Results: Over an average 6.8 years follow-up, 301 of 2,993 participants with a previous stroke at baseline had a recurrent stroke, while 818 of 26,689 participants who were stroke-free at baseline had a first stroke. Among those stroke-free at baseline, there was an age-by-race interaction (p = 0.0002), with a first stroke risk 2.70 (95% confidence interval: 1.86–3.91) times greater for black than white participants at age 45, but no racial disparity at age 85 (hazard ratio = 0.91; 95% confidence interval: 0.70–1.18). In contrast, there was no evidence of a higher risk of recurrent stroke at any age for black participants (p > 0.05). The association of traditional stroke risk factors was generally similar for first and recurrent stroke. Conclusion: The association of age and black race differs substantially on first vs recurrent stroke risk, with risk factors playing a similar role. PMID:26791153

  4. Music listening enhances cognitive recovery and mood after middle cerebral artery stroke.

    Science.gov (United States)

    Särkämö, Teppo; Tervaniemi, Mari; Laitinen, Sari; Forsblom, Anita; Soinila, Seppo; Mikkonen, Mikko; Autti, Taina; Silvennoinen, Heli M; Erkkilä, Jaakko; Laine, Matti; Peretz, Isabelle; Hietanen, Marja

    2008-03-01

    We know from animal studies that a stimulating and enriched environment can enhance recovery after stroke, but little is known about the effects of an enriched sound environment on recovery from neural damage in humans. In humans, music listening activates a wide-spread bilateral network of brain regions related to attention, semantic processing, memory, motor functions, and emotional processing. Music exposure also enhances emotional and cognitive functioning in healthy subjects and in various clinical patient groups. The potential role of music in neurological rehabilitation, however, has not been systematically investigated. This single-blind, randomized, and controlled trial was designed to determine whether everyday music listening can facilitate the recovery of cognitive functions and mood after stroke. In the acute recovery phase, 60 patients with a left or right hemisphere middle cerebral artery (MCA) stroke were randomly assigned to a music group, a language group, or a control group. During the following two months, the music and language groups listened daily to self-selected music or audio books, respectively, while the control group received no listening material. In addition, all patients received standard medical care and rehabilitation. All patients underwent an extensive neuropsychological assessment, which included a wide range of cognitive tests as well as mood and quality of life questionnaires, one week (baseline), 3 months, and 6 months after the stroke. Fifty-four patients completed the study. Results showed that recovery in the domains of verbal memory and focused attention improved significantly more in the music group than in the language and control groups. The music group also experienced less depressed and confused mood than the control group. These findings demonstrate for the first time that music listening during the early post-stroke stage can enhance cognitive recovery and prevent negative mood. The neural mechanisms potentially

  5. The Right Supramarginal Gyrus Is Important for Proprioception in Healthy and Stroke-Affected Participants: A Functional MRI Study

    Science.gov (United States)

    Ben-Shabat, Ettie; Matyas, Thomas A.; Pell, Gaby S.; Brodtmann, Amy; Carey, Leeanne M.

    2015-01-01

    Human proprioception is essential for motor control, yet its central processing is still debated. Previous studies of passive movements and illusory vibration have reported inconsistent activation patterns related to proprioception, particularly in high-order sensorimotor cortices. We investigated brain activation specific to proprioception, its laterality, and changes following stroke. Twelve healthy and three stroke-affected individuals with proprioceptive deficits participated. Proprioception was assessed clinically with the Wrist Position Sense Test, and participants underwent functional magnetic resonance imaging scanning. An event-related study design was used, where each proprioceptive stimulus of passive wrist movement was followed by a motor response of mirror ­copying with the other wrist. Left (LWP) and right (RWP) wrist proprioception were tested separately. Laterality indices (LIs) were calculated for the main cortical regions activated during proprioception. We found proprioception-related brain activation in high-order sensorimotor cortices in healthy participants especially in the supramarginal gyrus (SMG LWP z = 4.51, RWP z = 4.24) and the dorsal premotor cortex (PMd LWP z = 4.10, RWP z = 3.93). Right hemispheric dominance was observed in the SMG (LI LWP mean 0.41, SD 0.22; RWP 0.29, SD 0.20), and to a lesser degree in the PMd (LI LWP 0.34, SD 0.17; RWP 0.13, SD 0.25). In stroke-affected participants, the main difference in proprioception-related brain activation was reduced laterality in the right SMG. Our findings indicate that the SMG and PMd play a key role in proprioception probably due to their role in spatial processing and motor control, respectively. The findings from stroke-­affected individuals suggest that decreased right SMG function may be associated with decreased proprioception. We recommend that clinicians pay particular attention to the assessment and rehabilitation of proprioception following right hemispheric

  6. Stroke Rehabilitation

    Science.gov (United States)

    ... unique for each person. Although a majority of functional abilities may be restored soon after a stroke, recovery is an ongoing process. Effects of a Stroke Weakness (hemiparesis) or paralysis (hemiplegia) on one side of the body that may affect the whole ...

  7. Pediatric Stroke

    Science.gov (United States)

    ... of 3 and 10. In those with SCD, ischemic strokes most often occur in children under the age of 15 and adults over the age of 30, while hemorrhagic strokes most often occur in young adults between the ages of 20 and 30. ...

  8. The unification of mind: Integration of hemispheric semantic processing.

    Science.gov (United States)

    Hutchinson, Adele; Whitman, R Douglas; Abeare, Chris; Raiter, Jennifer

    2003-12-01

    Seventy-six participants performed a visual half-field lexical decision task at two different stimulus onset asynchronies (50 or 750 ms). Word targets were primed either by a highly associated word (e.g., CLEAN-DIRTY), a weakly associated word (e.g., CLEAN-TIDY), or an unrelated word (e.g., CLEAN-FAMILY) projected to either the same or opposite visual field (VF) as the target. In the short SOA, RVF-left hemisphere primes resulted in high associate priming regardless of target location (ipsilateral or contralateral to the prime) whereas LVF-right hemisphere primes produced both high and low associate priming across both target location conditions. In the long SOA condition, contralateral priming patterns converged, demonstrating only high associate priming in both VF locations. The results of this study demonstrate the critical role of interhemispheric transfer in semantic processing and indicate a need to elaborate current models of semantic processing.

  9. A predictive model for diagnosing stroke-related apraxia of speech.

    Science.gov (United States)

    Ballard, Kirrie J; Azizi, Lamiae; Duffy, Joseph R; McNeil, Malcolm R; Halaki, Mark; O'Dwyer, Nicholas; Layfield, Claire; Scholl, Dominique I; Vogel, Adam P; Robin, Donald A

    2016-01-29

    Diagnosis of the speech motor planning/programming disorder, apraxia of speech (AOS), has proven challenging, largely due to its common co-occurrence with the language-based impairment of aphasia. Currently, diagnosis is based on perceptually identifying and rating the severity of several speech features. It is not known whether all, or a subset of the features, are required for a positive diagnosis. The purpose of this study was to assess predictor variables for the presence of AOS after left-hemisphere stroke, with the goal of increasing diagnostic objectivity and efficiency. This population-based case-control study involved a sample of 72 cases, using the outcome measure of expert judgment on presence of AOS and including a large number of independently collected candidate predictors representing behavioral measures of linguistic, cognitive, nonspeech oral motor, and speech motor ability. We constructed a predictive model using multiple imputation to deal with missing data; the Least Absolute Shrinkage and Selection Operator (Lasso) technique for variable selection to define the most relevant predictors, and bootstrapping to check the model stability and quantify the optimism of the developed model. Two measures were sufficient to distinguish between participants with AOS plus aphasia and those with aphasia alone, (1) a measure of speech errors with words of increasing length and (2) a measure of relative vowel duration in three-syllable words with weak-strong stress pattern (e.g., banana, potato). The model has high discriminative ability to distinguish between cases with and without AOS (c-index=0.93) and good agreement between observed and predicted probabilities (calibration slope=0.94). Some caution is warranted, given the relatively small sample specific to left-hemisphere stroke, and the limitations of imputing missing data. These two speech measures are straightforward to collect and analyse, facilitating use in research and clinical settings. Copyright

  10. Stroke and Cerebrovascular Diseases Registry

    Science.gov (United States)

    2017-09-11

    Stroke; Acute Stroke; Acute Brain Injury; Ischemic Stroke; Hemorrhagic Stroke; Transient Ischemic Attack; Subarachnoid Hemorrhage; Cerebral Ischemia; Cerebral Infarction; Cerebral Stroke; Venous Sinus Thrombosis, Cranial

  11. Quality of life in patients with right- or left-sided brain tumours: literature review.

    Science.gov (United States)

    Palese, Alvisa; Lamanna, Francesca; Di Monte, Carmen; Calligaris, Sonia; Doretto, Mara; Criveller, Michela

    2008-06-01

    To determine if patients with left- or right-sided hemisphere neoplasm perceive their quality of life (QoL) differently. It is not clear whether patients with a lesion in the left hemisphere have a different QoL than those with a lesion in the right hemisphere. (1) In the pre-operative period, patients with a left-sided lesion may have different symptoms according to the position of the tumour. (2) Studies on patients with brain injury demonstrate an association between left frontal lesions and depression: depression can alter the patients' perception of QoL. (3) In the postoperative period, right-handed patients may be disadvantaged by surgical trauma to the motor cortex in the left hemisphere. (4) During the different phases of the disease, the various functions of the two hemispheres may influence the patient's capacity to control QoL; also, as suggested by authors, both the ego and the conscience are mostly located in the left hemisphere. This is the reason that patients with a left-sided lesion may perceive a worse QoL. A review of literature was carried out using the Medline database (1966-2007) and CINHAL (1982-2007), using the following Mesh Terms and key words: brain neoplasm, tumour or cancer, hemispheric dominance or laterality or right or left hemisphere, QoL. Seven studies emerged that documented non-homogeneous results and which included different populations. The association between QoL and the side of the lesion was evaluated. The lack of a substantial number of recent, robust follow-up studies investigating the QoL in patients at different stages of disease and treatment indicates that more research is needed. Relevance to clinical practice. Understanding the QoL in patients with brain neoplasm and the differences between right and left hemisphere sites of the neoplasm can help nurses develop different interventions and offer more guidance for effective clinical intervention.

  12. Right hemisphere role in cognitive reserve.

    Science.gov (United States)

    Robertson, Ian H

    2014-06-01

    High levels of education, occupational complexity, and/or premorbid intelligence are associated with lower levels of cognitive impairment than would be expected from a given brain pathology. This has been observed across a range of conditions including Alzheimer's disease (Roe et al., 2010), stroke (Ojala-Oksala et al., 2012), traumatic brain injury (Kesler et al., 2003), and penetrating brain injury (Grafman, 1986). This cluster of factors, which seemingly protect the brain from expressing symptoms of damage, has been termed "cognitive reserve" (Stern, 2012). The current review considers one possible neural network, which may contribute to cognitive reserve. Based on the evidence that the neurotransmitter, noradrenaline mediates cognitive reserve's protective effects (Robertson, 2013) this review identifies the neurocognitive correlates of noradrenergic (NA) activity. These involve a set of inter-related cognitive processes (arousal, sustained attention, response to novelty, and awareness) with a strongly right hemisphere, fronto-parietal localization, along with working memory, which is also strongly modulated by NA. It is proposed that this set of processes is one plausible candidate for partially mediating the protective effects of cognitive reserve. In addition to its biological effects on brain structure and function, NA function may also facilitate networks for arousal, novelty, attention, awareness, and working memory, which collectively provide for a set of additional, cognitive, mechanisms that help the brain adapt to age-related changes and disease. It is hypothesized that to the extent that the lateral surface of the right prefrontal lobe and/or the right inferior parietal lobe maintain structural (white and gray matter) and functional integrity and connectivity, cognitive reserve should benefit and behavioral expression of pathologic damage should thus be mitigated. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Individual Differences in Hemispheric Specialization

    Science.gov (United States)

    1987-11-01

    handers is of interest. Groups of dextro-sinistrals and stutterers (who were mostly right-handed) also had a left hand advantage. These findings were...in research of any sort. Procedure and objectives were not discussed with children or teachers . — • — - - w &BglS .-. ^’ Stimuli. The stimuli...any Q sort apparent to teachers or children. This led to the testing of two left- .^% handed children, but it was shown that

  14. Stroke Care 2: Stroke rehabilitation

    NARCIS (Netherlands)

    Langhorne, P.; Bernhardt, J.; Kwakkel, G.

    2011-01-01

    Stroke is a common, serious, and disabling global health-care problem, and rehabilitation is a major part of patient care. There is evidence to support rehabilitation in well coordinated multidisciplinary stroke units or through provision of early supported provision of discharge teams. Potentially

  15. Cross-sectional analysis of cognitive impairment and relative factors after acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    ZHOU Yu-ying

    2013-04-01

    Full Text Available Background Acute ischemic stroke may decline cognitive function and induce vascular dementia (VaD. In early identification of vascular cognitive impairment (VCI, active searching for relevant factors, effective and timely treatment can reduce or even prevent further decline of cognitive function. The purpose of this study is to investigate the cognitive impairment after acute ischemic stroke and its associated factors. Methods A total of 314 cases of acute ischemic stroke patients were recruited in this study. The Montreal Cognitive Assessment (MoCA was used to evaluate the degree of cognitive impairment. The American National Institutes of Health Stroke Scale (NIHSS was used to evaluate the extent of neurological deficit. The Barthel Index (BI was used to evaluate activities of daily living. Hamilton Depression Rating Scale (HAMD was used to evaluate the patients' mental or emotional state. Results Based on the examination results, post-stroke cognitive impairment (PSCI group were less educated ( P = 0.000 with lower BI score ( P = 0.008, higher HAMD score and higher NIHSS score ( P = 0.000, for all, and elevated serum high-sensitivity C-reactive protein (hs-CRP, P = 0.002 and glycosylated hemoglobin A1c (HbA1c levels (P = 0.005 than those in post-stroke no cognitive impairment (PSNCI group. In PSCI group, the concentration of serum hs-CRP and HbA1c, NIHSS and HAMD scores were negatively correlated with the MoCA rating (P < 0.05, for all; whereas, BI score was positively correlated with the MoCA rating (P < 0.05. The subjects in PSCI group had more cortical ischemic vascular disease (CIVD and left hemisphere ischemic vascular disease (LHIVD than subjects in PSNCI group ( P < 0.05. Logistic regression analysis indicated that lower education, history of diabetes, higher HAMD score, higher serum hs-CRP and HbA1c levels were independent risk factors for PSCI. Conclusion Cognitive impairment after acute ischemic stroke may be closely related to

  16. Hemichorea after ischemic stroke

    Directory of Open Access Journals (Sweden)

    Sadullah Saglam

    2016-03-01

    Full Text Available The deterioration of the balance between direct and indirect ways in the basal ganglia causes chorea. The lesions of contralateral basal ganglia, thalamus or the connection of them all together are responsible for this. Chorea can be observed during the course of metabolic and vascular diseases, neurodegenerative or hereditary diseases. Hyperkinetic movement disorders after acute ischemic stroke are reported as rare; however, hemichorea is the most frequent developing disorder of hyperkinetic movement as a result of cerebrovascular disease. In this case report, we presented two case who applied us with choreiform movements in his left half of the body after acute thalamic stroke. [Cukurova Med J 2016; 41(0.100: 29-32

  17. Perinatal stroke in Saudi children: clinical features and risk factors

    International Nuclear Information System (INIS)

    Salih, Mustafa A.; Al-Jarallah, Ahmed A.; Kentab, Anal Y.; Al-Nasser, Mohammad N.; Abdel-Gader, Abdel-Galil M.; Alorainy, Ibrahim A.; Hassan, Hamdy H.

    2006-01-01

    To describe the clinical features and presentations of perinatal stroke in a prospective and retrospective cohort of Saudi children and ascertain the risk factors. Patients with perinatal stroke were identified from within a cohort of 104 Saudi children who were evaluated at the Division of Pediatric Neurology at King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia from July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Neuroimaging for suspected cases of stroke consisted of cranial CT, MRI, or both. During the study period, 23 (22%) of 104 children (aged one months to 12 years) were diagnosed to have had perinatal stroke. The male: female ratio was 1.6:1. Ten (67%) of the 15 children who had unilateral ischemic involvement had their lesion in the left hemisphere. The presentation of the ischemic result was within 24-72 hours of life in 13 (57%) patients, and in 6 children (26%), motor impairment was recognized at or after the age of 4 months. Nine children (39%) had seizures at presentation. Pregnancy, labor, and delivery risk factors were ascertained in 18 (78%) cases. The most common of these included emergency cesarean section in 5 cases, and instrumental delivery in other 5. Screening for prothrombotic risk factors detected abnormalities in 6 (26%) patients on at least one test carried out between 2 months and 9 years of age. Four children (17%) had low protein C, which was associated low protein S and raised anticardiolipin antibodies (ACA) in one patient, and low antithrombin III in another. Low proteins S was detected in a 42-month-old boy. The abnormality in the sixth child was confined to raised ACA. The present study highlights the non-specific features by which stroke presents during the neonatal period. The data are in keeping with the potential role for inherited and acquired thrombophilia as being the underlying cause. However, the high prevalence of

  18. Hemispheric asymmetries and gender influence Rembrandt's portrait orientations.

    Science.gov (United States)

    Schirillo, J A

    2000-01-01

    For centuries painters have predominantly painted portraits with the model's left-cheek facing the viewer. This has been even more prevalent with females ( approximately 68%) than males ( approximately 56%). Numerous portraits painted by Rembrandt typify this unexplained phenomenon. In a preliminary experiment, subjects judged 24 emotional and social character traits in 20 portraits by Rembrandt. A factor analysis revealed that females with their left cheek exposed were judged to be much less socially appealing than less commonly painted right-cheeked females. Conversely, the more commonly painted right-cheeked males were judged to be more socially appealing than either left-cheeked males or females facing either direction. It is hypothesized that hemispheric asymmetries regulating emotional facial displays of approach and avoidance influenced the side of the face Rembrandt's models exposed due to prevailing social norms. A second experiment had different subjects judge a different collection of 20 portraits by Rembrandt and their mirror images. Mirror-reversed images produced the same pattern of results as their original orientation counterparts. Consequently, hemispheric asymmetries that specify the emotional expression on each side of the face are posited to account for the obtained results.

  19. Hemispheric asymmetries in speech perception: sense, nonsense and modulations.

    Directory of Open Access Journals (Sweden)

    Stuart Rosen

    Full Text Available The well-established left hemisphere specialisation for language processing has long been claimed to be based on a low-level auditory specialization for specific acoustic features in speech, particularly regarding 'rapid temporal processing'.A novel analysis/synthesis technique was used to construct a variety of sounds based on simple sentences which could be manipulated in spectro-temporal complexity, and whether they were intelligible or not. All sounds consisted of two noise-excited spectral prominences (based on the lower two formants in the original speech which could be static or varying in frequency and/or amplitude independently. Dynamically varying both acoustic features based on the same sentence led to intelligible speech but when either or both acoustic features were static, the stimuli were not intelligible. Using the frequency dynamics from one sentence with the amplitude dynamics of another led to unintelligible sounds of comparable spectro-temporal complexity to the intelligible ones. Positron emission tomography (PET was used to compare which brain regions were active when participants listened to the different sounds.Neural activity to spectral and amplitude modulations sufficient to support speech intelligibility (without actually being intelligible was seen bilaterally, with a right temporal lobe dominance. A left dominant response was seen only to intelligible sounds. It thus appears that the left hemisphere specialisation for speech is based on the linguistic properties of utterances, not on particular acoustic features.

  20. A pianist's recovery from stroke.

    Science.gov (United States)

    Toole, James F; Flowers, D Lynn; Burdette, Jonathan H; Absher, John R

    2007-08-01

    To determine alternative neural pathways for restitution of piano playing after right hemispheric infarction causing left arm and hand paralysis. Case report testing coordinated bimanual skills using structured motor skills tests and neuroimaging. A professional pianist sustained a lacunar infarction in the posterior limb of his right internal capsule, which resulted in left hemiparesis with immobilized left-hand and -finger movements persisting for 13 weeks. After 6 months, he had recovered bimanual coordinated piano skills by "ignoring" his left hand while concentrating or discussing subjects other than music while playing. A 63-year-old, male professional pianist. Detailed neurological examination including computed cranial tomography, functional magnetic resonance imaging, and positron emission tomography. Functional magnetic resonance imaging activation patterns correlated with rapid movements of fingers in each hand separately and together demonstrating that subcortical and cerebellar pathways were activated during skilled motor function of his left hand. Contralateral cerebral and cerebellar activation occurred with both left- and right-hand movements. During tapping of the left fingers, there was bilateral cerebellar, parietal, and left premotor strip and left thalamic activation. Patterns of activation relate to task performance and they are not similar to subjects engaged in simpler tasks such as finger opposition.

  1. Hemispheric asymmetry of the brain as a psycho-physiological basis of individual and typological features of the formation of a sense of humour

    Directory of Open Access Journals (Sweden)

    Shportun O.N.

    2016-05-01

    Full Text Available The article describes the psycho-physiological peculiarities of hemispheric asymmetry of the brain as the basis of individual and typological features of the formation of a sense of humour. The analysis of the impact of the functional brain hemispheric asymmetry on emotional, intellectual and physiological features of development of sense of humour in ontogeny is conducted. Analysis of studies of inter-hemispheric asymmetry of the brain makes it possible to ascertain the impact of the functioning of each hemisphere on the formation of the perception of humour. Studies show that in the process of developing of sense of humour, two functional hemispheres of the brain are involved. As the emotion of humour – is an intellectual emotion, and in the development of intelligence a lot of mental processes are involved, in the formation of humour two hemispheres of the brain are functioned. The right hemisphere is responsible for the emotional nature of humour (intonation, sound level of language, speed of response to a joke ..., the left hemisphere – for processing verbal information (content of the joke, category, purpose, content analysis .... After analysing the research of hemispheric functional asymmetry of the human brain, its psycho-physiological and neurochemical characteristics, it can be assumed that people with more developed left hemisphere in perceiving humour are more prone to displays of gelotophilia and “right hemisphere” people – show signs of gelotophobia and katagelasticism. Examining gender differences of hemisphere asymmetry of the brain, it can be argued that diagnosing sense of humour is important to take into account gender-specific functioning of hemispheres, because men have more clearly functioning the left hemisphere, and women – the right one. This fact of sexual peculiarities of functioning of inter-hemispheric asymmetry of the brain allows diagnosing objectively sense of humour, as well as different variations

  2. Hemispheric asymmetries in feature integration during visual word recognition.

    Science.gov (United States)

    Lindell, Annukka K; Arend, Isabel; Ward, Robert; Norton, Jennifer; Wathan, Jennifer

    2007-11-01

    Although the definitive source of the left hemisphere's superiority for visual word recognition remains illusive, some argue that the left (LH) and right (RH) hemispheres engage different strategies during early perceptual processes involved in stimulus encoding. In particular, it is proposed that the LH treats a word as a unitary perceptual group whereas the RH processes the letters comprising a word as a series of individual perceptual units. The present study investigated support for this processing distinction by examining hemispheric strategies for temporal integration using Prinzmetal and Millis-Wright's (1984) feature-binding paradigm. A total of 20 participants identified the colour and identity of a target letter, presented within a three-letter word (e.g., ART) or nonword (e.g., HRF), directed to their left or right visual field. Errors were classified on the basis of whether they involved substitution of a colour present within the stimulus but at a different location (ON error), or the substitution of a colour not present within the stimulus (OFF error). As anticipated, for word stimuli there was a higher proportion of OFF errors associated with trials directed to the RH, consistent with the notion that the LH treats words as single perceptual units and is hence biased toward miscombination of perceptual information present within the stimulus. The pattern of ON errors across stimulus type provided clear evidence of RH sequential encoding effects, with the number of errors increasing markedly across the ordinal position of the letters comprising the stimulus string. As such, these data provide new evidence that the LH's advantage for visual word recognition arises, at least in part, from the ability to encode verbal stimuli as single perceptual units.

  3. Right hemispheric contributions to fine auditory temporal discriminations: high-density electrical mapping of the duration mismatch negativity (MMN

    Directory of Open Access Journals (Sweden)

    Pierfilippo De Sanctis

    2009-04-01

    Full Text Available That language processing is primarily a function of the left hemisphere has led to the supposition that auditory temporal discrimination is particularly well-tuned in the left hemisphere, since speech discrimination is thought to rely heavily on the registration of temporal transitions. However, physiological data have not consistently supported this view. Rather, functional imaging studies often show equally strong, if not stronger, contributions from the right hemisphere during temporal processing tasks, suggesting a more complex underlying neural substrate. The mismatch negativity (MMN component of the human auditory evoked-potential (AEP provides a sensitive metric of duration processing in human auditory cortex and lateralization of MMN can be readily assayed when sufficiently dense electrode arrays are employed. Here, the sensitivity of the left and right auditory cortex for temporal processing was measured by recording the MMN to small duration deviants presented to either the left or right ear. We found that duration deviants differing by just 15% (i.e. rare 115 ms tones presented in a stream of 100 ms tones elicited a significant MMN for tones presented to the left ear (biasing the right hemisphere. However, deviants presented to the right ear elicited no detectable MMN for this separation. Further, participants detected significantly more duration deviants and committed fewer false alarms for tones presented to the left ear during a subsequent psychophysical testing session. In contrast to the prevalent model, these results point to equivalent if not greater right hemisphere contributions to temporal processing of small duration changes.

  4. Functional Ear (A)Symmetry in Brainstem Neural Activity Relevant to Encoding of Voice Pitch: A Precursor for Hemispheric Specialization?

    Science.gov (United States)

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Ananthakrishnan, Saradha; Bidelman, Gavin M.; Smalt, Christopher J.

    2011-01-01

    Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and…

  5. Determination of hemispheric language dominance using functional MRI : comparison of visual and auditory stimuli

    International Nuclear Information System (INIS)

    Yoo, Ic Ryung; Ahn, Kook Jin; Lee, Jae Mun; Kim, Tae

    1999-01-01

    To assess the difference between auditory and visual stimuli when determining hemispheric language dominance by using functional MRI. In ten healthy adult volunteers (8 right-handed, 1 left-handed, 1 ambidextrous), motor language activation in axial slices of frontal lobe was mapped on a Simens 1.5T Vision Plus system using single-shot EPI. Series of 120 consecutive images per section were acquired during three cycles of task activation and rest. During each activation, a series of four syllables was delivered by means of both a visual and auditory method, and the volunteers were asked to mentally generate words starting with each syllable. In both in ferior frontal gyri and whole frontal lobes, lateralization indices were calculated from the activated pixels. We determined the language dominant hemisphere, and compared the results of the visual method and the auditory method. Seven right-handed persons were left-hemisphere dominant, and one left-handed and one ambidex-trous person were right-hemisphere dominant. Five of nine persons demonstrated larger lateralization indices with the auditory method than the visual method, while the remaining four showed larger lateralization indices with the visual method. No statistically significant difference was noted when comparing the results of the two methods(p>0.05). When determining hemispheric language dominance using functional MRI, the two methods are equally appropriate

  6. Determination of hemispheric language dominance using functional MRI : comparison of visual and auditory stimuli

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Ic Ryung; Ahn, Kook Jin; Lee, Jae Mun [The Catholic Univ. of Korea, Seoul (Korea, Republic of); Kim, Tae [The Catholic Magnetic Resonance Research Center, Seoul (Korea, Republic of)

    1999-12-01

    To assess the difference between auditory and visual stimuli when determining hemispheric language dominance by using functional MRI. In ten healthy adult volunteers (8 right-handed, 1 left-handed, 1 ambidextrous), motor language activation in axial slices of frontal lobe was mapped on a Simens 1.5T Vision Plus system using single-shot EPI. Series of 120 consecutive images per section were acquired during three cycles of task activation and rest. During each activation, a series of four syllables was delivered by means of both a visual and auditory method, and the volunteers were asked to mentally generate words starting with each syllable. In both in ferior frontal gyri and whole frontal lobes, lateralization indices were calculated from the activated pixels. We determined the language dominant hemisphere, and compared the results of the visual method and the auditory method. Seven right-handed persons were left-hemisphere dominant, and one left-handed and one ambidex-trous person were right-hemisphere dominant. Five of nine persons demonstrated larger lateralization indices with the auditory method than the visual method, while the remaining four showed larger lateralization indices with the visual method. No statistically significant difference was noted when comparing the results of the two methods(p>0.05). When determining hemispheric language dominance using functional MRI, the two methods are equally appropriate.

  7. Bilateral cerebral hemispheric infarction associated with sildenafil citrate (Viagra) use.

    Science.gov (United States)

    Kim, K-K; Kim, D G; Ku, Y H; Lee, Y J; Kim, W-C; Kim, O J; Kim, H S

    2008-03-01

    Sildenafil citrate (Viagra) is one of the frequently prescribed drugs for men with erectile dysfunction. We describe a 52-year-old man with bilateral middle cerebral artery (MCA) territory infarction after sildenafil use. He ingested 100 mg of sildenafil and about 1 h later, he complained of chest discomfort, palpitation and dizziness followed by mental obtundation, global aphasia and left hemiparesis. Brain magnetic resonance imaging documented acute bilateral hemispheric infarction, and cerebral angiography showed occluded bilateral MCA. Despite significant bilateral MCA stenosis and cerebral infarction, systemic hypotension persisted for a day. We presume that cerebral infarction was caused by cardioembolism with sildenafil use.

  8. Hemisphericity and creativity. Group process and the dream factory.

    Science.gov (United States)

    Loye, D

    1988-09-01

    Traditionally, creativity has been studied as an aspect of the psychology of personality. Recent brain research--for example, hemisphericity study--provides a new physiologic grounding for such studies. Particularly needed now are creativity studies to relate both brain physiology and personality to group process. This article is the report of such a study applying systems research to an exploration of creativity in the motion picture-television industry. Findings include the identification of both right and left brain models and creative phases within cycles phenomena in group process creativity. Implications for psychotherapy and a wide range of fields are examined.

  9. ARE LEFT HANDED SURGEONS LEFT OUT?

    OpenAIRE

    SriKamkshi Kothandaraman; Balasubramanian Thiagarajan

    2012-01-01

    Being a left-handed surgeon, more specifically a left-handed ENT surgeon, presents a unique pattern of difficulties.This article is an overview of left-handedness and a personal account of the specific difficulties a left-handed ENT surgeon faces.

  10. Gaussian mixture modeling of hemispheric lateralization for language in a large sample of healthy individuals balanced for handedness.

    Directory of Open Access Journals (Sweden)

    Bernard Mazoyer

    Full Text Available Hemispheric lateralization for language production and its relationships with manual preference and manual preference strength were studied in a sample of 297 subjects, including 153 left-handers (LH. A hemispheric functional lateralization index (HFLI for language was derived from fMRI acquired during a covert sentence generation task as compared with a covert word list recitation. The multimodal HFLI distribution was optimally modeled using a mixture of 3 and 4 Gaussian functions in right-handers (RH and LH, respectively. Gaussian function parameters helped to define 3 types of language hemispheric lateralization, namely "Typical" (left hemisphere dominance with clear positive HFLI values, 88% of RH, 78% of LH, "Ambilateral" (no dominant hemisphere with HFLI values close to 0, 12% of RH, 15% of LH and "Strongly-atypical" (right-hemisphere dominance with clear negative HFLI values, 7% of LH. Concordance between dominant hemispheres for hand and for language did not exceed chance level, and most of the association between handedness and language lateralization was explained by the fact that all Strongly-atypical individuals were left-handed. Similarly, most of the relationship between language lateralization and manual preference strength was explained by the fact that Strongly-atypical individuals exhibited a strong preference for their left hand. These results indicate that concordance of hemispheric dominance for hand and for language occurs barely above the chance level, except in a group of rare individuals (less than 1% in the general population who exhibit strong right hemisphere dominance for both language and their preferred hand. They call for a revisit of models hypothesizing common determinants for handedness and for language dominance.

  11. Pediatric stroke

    International Nuclear Information System (INIS)

    Hoermann, M.

    2008-01-01

    Stroke in childhood has gained increasingly more attention and is accepted as an important disease in childhood. The reasons for this severe event and the consequences for the rest of the life are totally different than for adults. This is also true for the diagnosis and therapy. This paper gives a comprehensive overview on the characteristics of pediatric stroke to assist radiologists in making a rapid and safe diagnosis in order to identify the underlying disease. (orig.) [de

  12. The effect of cognitive load on hemispheric asymmetries in true and false memory.

    Science.gov (United States)

    Tat, Michael J; Azuma, Tamiko

    2016-01-01

    Studies examining hemispheric asymmetries in false memory have shown that the right hemisphere (RH) is more susceptible to false memories compared to the left hemisphere (LH). Theories suggest that hemispheric asymmetries in true and false memory may be due to differences in representational coding and the use of top-down mechanisms in each hemisphere. In the current study, the Deese-Roediger-McDermott false memory paradigm was used in conjunction with divided visual field presentation to examine the role of top-down mechanisms in hemispheric asymmetries of true and false memory. In Experiment 1, participants studied lists of related words while completing secondary cognitive load tasks. In Experiment 2, the secondary tasks were administered during memory retrieval instead of memory encoding. Results revealed that cognitive loads imposed during the study phase influenced veridical memory in the LH more than the RH, but cognitive loads imposed during retrieval did not influence veridical memory in either hemisphere. Surprisingly, false memory rates were not influenced by cognitive loads and were higher in the LH. These data provide evidence that, at least for veridical memory, top-down control mechanisms are used more readily for the encoding of information into memory in the LH compared to the RH.

  13. Hemispheric differences in electrical and hemodynamic responses during hemifield visual stimulation with graded contrasts.

    Science.gov (United States)

    Si, Juanning; Zhang, Xin; Zhang, Yujin; Jiang, Tianzi

    2017-04-01

    A multimodal neuroimaging technique based on electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) was used with horizontal hemifield visual stimuli with graded contrasts to investigate the retinotopic mapping more fully as well as to explore hemispheric differences in neuronal activity, the hemodynamic response, and the neurovascular coupling relationship in the visual cortex. The fNIRS results showed the expected activation over the contralateral hemisphere for both the left and right hemifield visual stimulations. However, the EEG results presented a paradoxical lateralization, with the maximal response located over the ipsilateral hemisphere but with the polarity inversed components located over the contralateral hemisphere. Our results suggest that the polarity inversion as well as the latency advantage over the contralateral hemisphere cause the amplitude of the VEP over the contralateral hemisphere to be smaller than that over the ipsilateral hemisphere. Both the neuronal and hemodynamic responses changed logarithmically with the level of contrast in the hemifield visual stimulations. Moreover, the amplitudes and latencies of the visual evoked potentials (VEPs) were linearly correlated with the hemodynamic responses despite differences in the slopes.

  14. Hemispheric asymmetry in the processing of negative and positive words: a divided field study.

    Science.gov (United States)

    Holtgraves, Thomas; Felton, Adam

    2011-06-01

    Research on the lateralisation of brain functions for emotion has yielded different results as a function of whether it is the experience, expression, or perceptual processing of emotion that is examined. Further, for the perception of emotion there appear to be differences between the processing of verbal and nonverbal stimuli. The present research examined the hemispheric asymmetry in the processing of verbal stimuli varying in emotional valence. Participants performed a lexical decision task for words varying in affective valence (but equated in terms of arousal) that were presented briefly to the right or left visual field. Participants were significantly faster at recognising positive words presented to the right visual field/left hemisphere. This pattern did not occur for negative words (and was reversed for high arousal negative words). These results suggest that the processing of verbal stimuli varying in emotional valence tends to parallel hemispheric asymmetry in the experience of emotion.

  15. On the Viability of Diffusion MRI-Based Microstructural Biomarkers in Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Ilaria Boscolo Galazzo

    2018-02-01

    Full Text Available Recent tract-based analyses provided evidence for the exploitability of 3D-SHORE microstructural descriptors derived from diffusion MRI (dMRI in revealing white matter (WM plasticity. In this work, we focused on the main open issues left: (1 the comparative analysis with respect to classical tensor-derived indices, i.e., Fractional Anisotropy (FA and Mean Diffusivity (MD; and (2 the ability to detect plasticity processes in gray matter (GM. Although signal modeling in GM is still largely unexplored, we investigated their sensibility to stroke-induced microstructural modifications occurring in the contralateral hemisphere. A more complete picture could provide hints for investigating the interplay of GM and WM modulations. Ten stroke patients and ten age/gender-matched healthy controls were enrolled in the study and underwent diffusion spectrum imaging (DSI. Acquisitions at three and two time points (tp were performed on patients and controls, respectively. For all subjects and acquisitions, FA and MD were computed along with 3D-SHORE-based indices [Generalized Fractional Anisotropy (GFA, Propagator Anisotropy (PA, Return To the Axis Probability (RTAP, Return To the Plane Probability (RTPP, and Mean Square Displacement (MSD]. Tract-based analysis involving the cortical, subcortical and transcallosal motor networks and region-based analysis in GM were successively performed, focusing on the contralateral hemisphere to the stroke. Reproducibility of all the indices on both WM and GM was quantitatively proved on controls. For tract-based, longitudinal group analyses revealed the highest significant differences across the subcortical and transcallosal networks for all the indices. The optimal regression model for predicting the clinical motor outcome at tp3 included GFA, PA, RTPP, and MSD in the subcortical network in combination with the main clinical information at baseline. Region-based analysis in the contralateral GM highlighted the ability of

  16. Left subclavian artery revascularization as part of thoracic stent grafting

    NARCIS (Netherlands)

    Saouti, N.; Hindori, V.; Morshuis, W.J.; Heijmen, R.H.

    2015-01-01

    OBJECTIVES: Intentional covering of the left subclavian artery (LSA) as part of thoracic endovascular aortic repair (TEVAR) can cause (posterior) strokes or left arm malperfusion. LSA revascularization can be done as prophylaxis against, or as treatment of, these complications. We report our

  17. Effects of hemisphere speech dominance and seizure focus on patterns of behavioral response errors for three types of stimuli.

    Science.gov (United States)

    Rausch, R; MacDonald, K

    1997-03-01

    We used a protocol consisting of a continuous presentation of stimuli with associated response requests during an intracarotid sodium amobarbital procedure (IAP) to study the effects of hemisphere injected (speech dominant vs. nondominant) and seizure focus (left temporal lobe vs. right temporal lobe) on the pattern of behavioral response errors for three types of visual stimuli (pictures of common objects, words, and abstract forms). Injection of the left speech dominant hemisphere compared to the right nondominant hemisphere increased overall errors and affected the pattern of behavioral errors. The presence of a seizure focus in the contralateral hemisphere increased overall errors, particularly for the right temporal lobe seizure patients, but did not affect the pattern of behavioral errors. Left hemisphere injections disrupted both naming and reading responses at a rate similar to that of matching-to-sample performance. Also, a short-term memory deficit was observed with all three stimuli. Long-term memory testing following the left hemisphere injection indicated that only for pictures of common objects were there fewer errors during the early postinjection period than for the later long-term memory testing. Therefore, despite the inability to respond to picture stimuli, picture items, but not words or forms, could be sufficiently encoded for later recall. In contrast, right hemisphere injections resulted in few errors, with a pattern suggesting a mild general cognitive decrease. A selective weakness in learning unfamiliar forms was found. Our findings indicate that different patterns of behavioral deficits occur following the left vs. right hemisphere injections, with selective patterns specific to stimulus type.

  18. Decreased GABA levels in the symptomatic hemisphere after Transient Ischaemic Attack

    DEFF Research Database (Denmark)

    Figlewski, Krystian; Andersen, Henning; Stærmose, Tobias

    Background and aims: In patients with stroke the GABA level is decreased in the lesioned hemisphere which may facilitate neurological recovery. In this study we aimed to determine the cortical levels of GABA and glutamate in patients after transient ischemic attack (TIA). Methods: Ten first......-time TIA patients with unilateral motor symptoms from upper limb and 10 healthy subjects underwent Magnetic Resonance Spectroscopy with SPECIAL technique. GABA and glutamate were measured in the hand area of the primary motor cortex (M1) in the symptomatic hemisphere. Results: Both GABA:Cr (p=0.......003) and Glutamate:Cr (p=0.0035) ratios were significantly lower in the symptomatic hemisphere of TIA patients than in healthy subjects. No difference was found in grey matter content within the scanned voxel (p=0.26) Conclusion: Even though the neurologigal function was reestablished, our study showed reduced GABA...

  19. Noninvasive brain stimulation for treatment of right- and left-handed poststroke aphasics.

    Science.gov (United States)

    Heiss, Wolf-Dieter; Hartmann, Alexander; Rubi-Fessen, Ilona; Anglade, Carole; Kracht, Lutz; Kessler, Josef; Weiduschat, Nora; Rommel, Thomas; Thiel, Alexander

    2013-01-01

    Accumulating evidence from single case studies, small case series and randomized controlled trials seems to suggest that inhibitory noninvasive brain stimulation (NIBS) over the contralesional inferior frontal gyrus (IFG) of right-handers in conjunction with speech and language therapy (SLT) improves recovery from poststroke aphasia. Application of inhibitory NIBS to improve recovery in left-handed patients has not yet been reported. A total of 29 right-handed subacute poststroke aphasics were randomized to receive either 10 sessions of SLT following 20 min of inhibitory repetitive transcranial magnetic stimulation (rTMS) over the contralesional IFG or 10 sessions of SLT following sham stimulation; 2 left-handers were treated according to the same protocol with real rTMS. Language activation patterns were assessed with positron emission tomography prior to and after the treatment; 95% confidence intervals for changes in language performance scores and the activated brain volumes in both hemispheres were derived from TMS- and sham-treated right-handed patients and compared to the same parameters in left-handers. Right-handed patients treated with rTMS showed better recovery of language function in global aphasia test scores (t test, p left-handed patients also improved, with 1 patient within the confidence limits of TMS-treated right-handers (23 points, 15.9-28.9) and the other patient within the limits of sham-treated subjects (8 points, 2.8-14.5). Both patients exhibited only a very small interhemispheric shift, much less than expected in TMS-treated right-handers, and more or less consolidated initially active networks in both hemispheres. Inhibitory rTMS over the nondominant IFG appears to be a safe and effective treatment for right-handed poststroke aphasics. In the 2 cases of left-handed aphasics no deterioration of language performance was observed with this protocol. However, therapeutic efficiency is less obvious and seems to be more related to the

  20. An ERP assessment of hemispheric projections in foveal and extrafoveal word recognition.

    Directory of Open Access Journals (Sweden)

    Timothy R Jordan

    Full Text Available BACKGROUND: The existence and function of unilateral hemispheric projections within foveal vision may substantially affect foveal word recognition. The purpose of this research was to reveal these projections and determine their functionality. METHODOLOGY: Single words (and pseudowords were presented to the left or right of fixation, entirely within either foveal or extrafoveal vision. To maximize the likelihood of unilateral projections for foveal displays, stimuli in foveal vision were presented away from the midline. The processing of stimuli in each location was assessed by combining behavioural measures (reaction times, accuracy with on-line monitoring of hemispheric activity using event-related potentials recorded over each hemisphere, and carefully-controlled presentation procedures using an eye-tracker linked to a fixation-contingent display. PRINCIPAL FINDINGS: Event-related potentials 100-150 ms and 150-200 ms after stimulus onset indicated that stimuli in extrafoveal and foveal locations were projected unilaterally to the hemisphere contralateral to the presentation hemifield with no concurrent projection to the ipsilateral hemisphere. These effects were similar for words and pseudowords, suggesting this early division occurred before word recognition. Indeed, event-related potentials revealed differences between words and pseudowords 300-350 ms after stimulus onset, for foveal and extrafoveal locations, indicating that word recognition had now occurred. However, these later event-related potentials also revealed that the hemispheric division observed previously was no longer present for foveal locations but remained for extrafoveal locations. These findings closely matched the behavioural finding that foveal locations produced similar performance each side of fixation but extrafoveal locations produced left-right asymmetries. CONCLUSIONS: These findings indicate that an initial division in unilateral hemispheric projections occurs in

  1. An ERP Assessment of Hemispheric Projections in Foveal and Extrafoveal Word Recognition

    Science.gov (United States)

    Jordan, Timothy R.; Fuggetta, Giorgio; Paterson, Kevin B.; Kurtev, Stoyan; Xu, Mengyun

    2011-01-01

    Background The existence and function of unilateral hemispheric projections within foveal vision may substantially affect foveal word recognition. The purpose of this research was to reveal these projections and determine their functionality. Methodology Single words (and pseudowords) were presented to the left or right of fixation, entirely within either foveal or extrafoveal vision. To maximize the likelihood of unilateral projections for foveal displays, stimuli in foveal vision were presented away from the midline. The processing of stimuli in each location was assessed by combining behavioural measures (reaction times, accuracy) with on-line monitoring of hemispheric activity using event-related potentials recorded over each hemisphere, and carefully-controlled presentation procedures using an eye-tracker linked to a fixation-contingent display. Principal Findings Event-related potentials 100–150 ms and 150–200 ms after stimulus onset indicated that stimuli in extrafoveal and foveal locations were projected unilaterally to the hemisphere contralateral to the presentation hemifield with no concurrent projection to the ipsilateral hemisphere. These effects were similar for words and pseudowords, suggesting this early division occurred before word recognition. Indeed, event-related potentials revealed differences between words and pseudowords 300–350 ms after stimulus onset, for foveal and extrafoveal locations, indicating that word recognition had now occurred. However, these later event-related potentials also revealed that the hemispheric division observed previously was no longer present for foveal locations but remained for extrafoveal locations. These findings closely matched the behavioural finding that foveal locations produced similar performance each side of fixation but extrafoveal locations produced left-right asymmetries. Conclusions These findings indicate that an initial division in unilateral hemispheric projections occurs in foveal vision

  2. Individualized model predicts brain current flow during transcranial direct-current stimulation treatment in responsive stroke patient.

    Science.gov (United States)

    Datta, Abhishek; Baker, Julie M; Bikson, Marom; Fridriksson, Julius

    2011-07-01

    Although numerous published reports have demonstrated the beneficial effects of transcranial direct-current stimulation (tDCS) on task performance, fundamental questions remain regarding the optimal electrode configuration on the scalp. Moreover, it is expected that lesioned brain tissue will influence current flow and should therefore be considered (and perhaps leveraged) in the design of individualized tDCS therapies for stroke. The current report demonstrates how different electrode configurations influence the flow of electrical current through brain tissue in a patient who responded positively to a tDCS treatment targeting aphasia. The patient, a 60-year-old man, sustained a left hemisphere ischemic stroke (lesion size = 87.42 mL) 64 months before his participation. In this study, we present results from the first high-resolution (1 mm(3)) model of tDCS in a brain with considerable stroke-related damage; the model was individualized for the patient who received anodal tDCS to his left frontal cortex with the reference cathode electrode placed on his right shoulder. We modeled the resulting brain current flow and also considered three additional reference electrode positions: right mastoid, right orbitofrontal cortex, and a "mirror" configuration with the anode over the undamaged right cortex. Our results demonstrate the profound effect of lesioned tissue on resulting current flow and the ability to modulate current pattern through the brain, including perilesional regions, through electrode montage design. The complexity of brain current flow modulation by detailed normal and pathologic anatomy suggest: (1) That computational models are critical for the rational interpretation and design of individualized tDCS stroke-therapy; and (2) These models must accurately reproduce head anatomy as shown here. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Functional Hemispheric (Asymmetries in the Aged Brain—Relevance for Working Memory

    Directory of Open Access Journals (Sweden)

    Madalena Esteves

    2018-03-01

    Full Text Available Functional hemispheric asymmetries have been described in different cognitive processes, such as decision-making and motivation. Variations in the pattern of left/right activity have been associated with normal brain functioning, and with neuropsychiatric diseases. Such asymmetries in brain activity evolve throughout life and are thought to decrease with aging, but clear associations with cognitive function have never been established. Herein, we assessed functional laterality during a working memory task (N-Back in a healthy aging cohort (over 50 years old and associated these asymmetries with performance in the test. Activity of lobule VI of the cerebellar hemisphere and angular gyrus was found to be lateralized to the right hemisphere, while the precentral gyrus presented left > right activation during this task. Interestingly, 1-Back accuracy was positively correlated with left > right superior parietal lobule activation, which was mostly due to the influence of the left hemisphere. In conclusion, although regions were mostly symmetrically activated during the N-Back task, performance in working memory in aged individuals seems to benefit from lateralized involvement of the superior parietal lobule.

  4. Increasing Northern Hemisphere water deficit

    Science.gov (United States)

    McCabe, Gregory J.; Wolock, David M.

    2015-01-01

    A monthly water-balance model is used with CRUTS3.1 gridded monthly precipitation and potential evapotranspiration (PET) data to examine changes in global water deficit (PET minus actual evapotranspiration) for the Northern Hemisphere (NH) for the years 1905 through 2009. Results show that NH deficit increased dramatically near the year 2000 during both the cool (October through March) and warm (April through September) seasons. The increase in water deficit near 2000 coincides with a substantial increase in NH temperature and PET. The most pronounced increases in deficit occurred for the latitudinal band from 0 to 40°N. These results indicate that global warming has increased the water deficit in the NH and that the increase since 2000 is unprecedented for the 1905 through 2009 period. Additionally, coincident with the increase in deficit near 2000, mean NH runoff also increased due to increases in P. We explain the apparent contradiction of concurrent increases in deficit and increases in runoff.

  5. Driving After a Stroke

    Science.gov (United States)

    ... Stroke Association.org Professionals for Stroke Association.org Shop for Stroke Association.org Support for Stroke Association. ... a wheelchair accessible or modified van, truck or car can provide the assurance you need to feel ...

  6. Praxial disorders in focal lesions of cerebral hemispheres

    Directory of Open Access Journals (Sweden)

    Jorge Murillo Duran

    2007-11-01

    Full Text Available The purpose of this work is to analyze paraxial difficulties i.e, functional disorders in movementresulting from cerebral tissue lesions. In accordance with the literature on the subject, the following definition, the following definition of apraxia has been accepted: “Apraxia is inability in properly executing kinetic tasks without impairment or loss of motor or sensory functions or ataxia with would condition such inability”. “Proper execution” used in this definition concerns not only the effect of the action but also means of its realization. “Kinetic tasks” signify all aspects of motor activity defined by instructions, irrespective of the type of instruction (verbal or gestures, and regardless of whether it required −in the final effect− imitating the movement of the investigator or whether they were performed independently. The methodology has been based in the principle on Luria’s works.Deliberations on praxial disorders were based on investigation results embracing 90 patients with focal cerebral lesions. In fifty cases, changes were localized in the left cerebral hemisphere, in forty cases−in the right hemisphere. The summing up the results concerning a global comparison between cerebral hemispheres, indicate the following regularities: Results achieved made it possible to form the opinion that not all of the generally accepted tests investigating praxia in persons with cerebral lesions are solved faultlessly by healthy individuals; thus, a faulty execution should not always be regarded as a sign of pathological functioning of the cerebral tissue as a result of lesion.

  7. Validation of the language component of the Addenbrooke's Cognitive Examination--Revised (ACE-R) as a screening tool for aphasia in stroke patients.

    Science.gov (United States)

    Gaber, Tarek A-Z K; Parsons, Faye; Gautam, Vidushi

    2011-09-01

    Several tests are available for aphasia screening following stroke. However, some of them have shortcomings such as need of specialist knowledge, low sensitivity and/or specificity and lengthy administration time. Our study aims to evaluate the language component of the Addenbrooke's Cognitive Examination--Revised (ACE-R) as a screening tool for aphasia in stroke patients. The language component of ACE-R was administered to consecutive patients admitted to a post-acute stroke unit. Patients who were medically unstable or had a significant history of sensory impairment or mental health issues were excluded. The test was administered by two junior doctors with basic training in ACE-R administration. Patients recruited were also assessed by an experienced speech and language therapist (SLT). The results of the two assessments were documented by a different member of the team and the SLT results were used as the benchmark to calculate the ACE-R language component sensitivity and specificity.   Fifty-nine participants were recruited and 27 of them were women. The mean age was 72 (SD 11.9). Thirty-four participants had left and 11 right hemisphere stroke. Fourteen had bilateral affection. Six participants were left handed. A cut-off value of 22/26 of ACE-R language component showed 100% specificity and 83.1% sensitivity, while a cut-off value of 16/26 had 88.2% specificity and 100% sensitivity. Our results suggest that the language component of ACE-R has a satisfactory sensitivity and specificity compared with other screening tests used in strokes. It is easy to administer and free to use. © 2010 The Authors. Australasian Journal on Ageing © 2010 ACOTA.

  8. A crucial role for the cortico-striato-cortical loop in the pathogenesis of stroke-related neurogenic stuttering.

    Science.gov (United States)

    Theys, Catherine; De Nil, Luc; Thijs, Vincent; van Wieringen, Astrid; Sunaert, Stefan

    2013-09-01

    Neurogenic stuttering is an acquired speech disorder characterized by the occurrence of stuttering-like dysfluencies following brain damage. Because the onset of stuttering in these patients is associated with brain lesions, this condition provides a unique opportunity to study the neural processes underlying speech dysfluencies. Lesion localizations of 20 stroke subjects with neurogenic stuttering and 17 control subjects were compared using voxel-based lesion symptom mapping. The results showed nine left-hemisphere areas associated with the presence of neurogenic stuttering. These areas were largely overlapping with the cortico-basal ganglia-cortical network comprising the inferior frontal cortex, superior temporal cortex, intraparietal cortex, basal ganglia, and their white matter interconnections through the superior longitudinal fasciculus and internal capsule. These results indicated that stroke-induced neurogenic stuttering is not associated with neural dysfunction in one specific brain area but can occur following one or more lesion throughout the cortico-basal ganglia-cortical network. It is suggested that the onset of neurogenic stuttering in stroke subjects results from a disintegration of neural functions necessary for fluent speech. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

  9. [Clinical study of post-stroke speech apraxia treated with scalp electric acupuncture under anatomic orientation and rehabilitation training].

    Science.gov (United States)

    Jiang, Yujuan; Yang, Yuxia; Xiang, Rong; Chang, E; Zhang, Yanchun; Zuo, Bingfang; Zhang, Qianwei

    2015-07-01

    To compare the differences in the clinical efficacy on post-stroke speech disorder between scalp electric acupuncture (EA) under anatomic orientation combined with rehabilitation training and simple rehabilitation training. Sixty patients of post-stroke speech apraxia were randomized into an observation group and a control group, 30 cases in each one. In the observation group, under anatomic orientation, the scalp EA was adopted to the dominant hemisphere Broca area on the left cerebrum. Additionally, the speech rehabilitation training was combined. In the control group, the speech rehabilitation training was simply,used. The treatment lasted for 4 weeks totally. The speech movement program module in the psychological language assessment and treatment system of Chinese aphasia was used for the evident of efficacy assessment. The scores of counting, singing scale, repeating phonetic alphabet, repeating monosyllable and repeating disyllable were observed in the patients of the two groups. The assessment was done separately on the day of grouping and 4 weeks after treatment. In 4 weeks of treatment, the scores of counting, singing scale, repeating phonetic alphabet, repeating monosyllable and repeating disyllable were all improved as compared with those before treatment in the two groups (all Pspeech rehabilitation training obviously improves speech apraxia in stroke patients so that the speech disorder cani be relieved. The efficacy is better than that in simple rehabilitation training.

  10. White matter structure and clinical characteristics of stroke patients: A diffusion tensor MRI study.

    Science.gov (United States)

    Ueda, Ryo; Yamada, Naoki; Kakuda, Wataru; Abo, Masahiro; Senoo, Atsushi

    2016-03-15

    Fractional anisotropy has been used in many studies that examined post-stroke changes in white matter. This study was performed to clarify cerebral white matter changes after stroke using generalized fractional anisotropy (GFA). White matter structure was visualized using diffusion tensor imaging in 72 patients with post-stroke arm paralysis. Exercise-related brain regions were examined in cerebral white matter using GFA. The relationship between GFA and clinical characteristics was examined. Overall, the mean GFA of the lesioned hemisphere was significantly lower than that of the non-lesioned hemisphere (PBrodmann area 5 of the non-lesioned hemisphere. Age correlated negatively with GFA in Brodmann areas 5 and 7 of the lesioned hemisphere. Though these results may be due to a decrease in the frequency of use of the paralyzed limb over time, GFA overall was significantly and negatively affected by the subject's age. The GFA values of patients with paralysis of the dominant hand were significantly different from those of patients with paralysis of the nondominant hand in Brodmann areas 4 and 6 of the non-lesioned hemisphere and Brodmann area 4 of the lesioned hemisphere (P<0.05). The stroke size and location were not associated with GFA differences. Differences between the GFA of the lesioned and non-lesioned hemispheres varied depending on the affected brain region, age at onset of paralysis, and paralysis of the dominant or non-dominant hand. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Frontal EEG delta/alpha ratio and screening for post-stroke cognitive deficits: the power of four electrodes.

    Science.gov (United States)

    Schleiger, Emma; Sheikh, Nabeel; Rowland, Tennille; Wong, Andrew; Read, Stephen; Finnigan, Simon

    2014-10-01

    This study analysed correlations between post-stroke, quantitative electroencephalographic (QEEG) indices, and cognition-specific, functional outcome measures. Results were compared between QEEG indices calculated from the standard 19 versus 4 frontal (or 4 posterior) electrodes to assess the feasibility and efficacy of employing a reduced electrode montage. Resting-state EEG was recorded at the bedside within 62-101 h after onset of symptoms of middle cerebral artery, ischaemic stroke (confirmed radiologically). Relative power for delta, theta, alpha and beta, delta/alpha ratio (DAR) and pairwise-derived brain symmetry index (pdBSI) were averaged; over all electrodes (global), over F3, F4, F7, F8 (frontal) and P3, P4, T5, T6 (posterior). The functional independence measure and functional assessment measure (FIM-FAM) was administered at mean 105 days post-stroke. Total (30 items) and cognition-specific (5 items) FIM-FAM scores were correlated with QEEG indices using Spearman's coefficient, with a Bonferroni correction. Twenty-five patients were recruited, 4 died within 3 months and 1 was lost to follow-up. Hence 20 cases (10 female; 9 left hemisphere; mean age 68 years, range 38-84) were analysed. Two QEEG indices demonstrated highly-significant correlations with cognitive outcomes: frontal DAR (ρ = -0.664, p ≤ 0.001) and global, relative alpha power (ρ = 0.67, p ≤ 0.001). After correction there were no other significant correlations. Alpha activity - particularly frontally - may index post-stroke attentional capacity, which appears to be a key determinant of functional and cognitive outcomes. Likewise frontal delta pathophysiology influences such outcomes. Pending further studies, DAR from 4 frontal electrodes may inform early screening for post-MCA stroke cognitive deficits, and thereby, clinical decisions. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Left atrial appendage occlusion with Amplatzer Cardio Plug is an acceptable therapeutic option for prevention of stroke recurrence in patients with non-valvular atrial fibrillation and contraindication or failure of oral anticoagulation with acenocumarol

    OpenAIRE

    Hawkes, Maximiliano A.; Pertierra, Lucía; Rodriguez-Lucci, Federico; Pujol-Lereis, Virginia A.; Ameriso, Sebastián F.

    2016-01-01

    ABSTRACT Left atrial appendage occlusion (LAAO) appears as a therapeutic option for some atrial fibrillation patients not suitable for oral anticoagulation because an increased hemorrhagic risk or recurrent ischemic events despite anticoagulant treatment. Methods Report of consecutive atrial fibrillation patients treated with LAAO with Amplatzer Cardio Plug because contraindication or failure of oral anticoagulation with acenocumarol. CHA2DS2VASC, HAS-BLED, NIHSS, mRS, procedural complicati...

  13. Communication Impairments in Patients with Right Hemisphere Damage

    Directory of Open Access Journals (Sweden)

    Abusamra, Valeria

    2009-06-01

    Full Text Available Right brain damages can manifest deficits of communicative skills, which sometimes cause an important inability.The communication impairments following a right hemisphere damage are distinct from those in aphasia and may affect discursive, lexico-semantic, pragmatic, and prosodic components of communication. It is calculated that this troubles affect almost a 50% of this patients.However, these impairments have essentially been studied separately and their possible coexistence in a same individual is still unknown. Moreover, the clinical profiles of communication impairments following a right hemisphere damage, including their correlation with underlying cognitive deficits, are still unreported. The goal of this article is to offer an overview of the verbal communication deficits that can be found in right-hemisphere-damaged individuals. These deficits can interfere, at different levels, with prosody, the semantic processing of words and discourse and pragmatic abilities. In spite of the incapability that they produce, communicational impairments in right brain damaged are usually neglected. Probably, the sub-diagnostic is due to the lack of an appropriate classification or to the absent of adequate assessment tools. In fact, patients with right brain damages might present harsh communicational deficits but perform correctly on aphasia tests because the last ones are not designed to detect this kind of deficit but left brain damaged impairments. Increasing our knowledge about the role of the right-hemisphere in verbal communication will have major theoretical and clinical impacts; it could facilitate the diagnosis of right brain patients in the clinical circle and it will help to lay the foundations to elaborate methods and strategies of intervention.

  14. Cor triatriatum and stroke.

    Science.gov (United States)

    Diestro, Jose Danilo Bengzon; Regaldo, Joseph Justin Hipolito; Gonzales, Eddieson Masangcay; Dorotan, Maria Kristina Casanova; Espiritu, Adrian Isidro; Pascual, Jose Leonard Rivera

    2017-08-08

    Cor triatriatum sinistrum (CTS) is a congenital anomaly where the left atrium is divided into two compartments by a fibromuscular membrane. This report aims to add to the literature on a rare cardiac condition that can cause neurological morbidity. We report a case of a 19-year-old female with an infarct in the right middle cerebral artery (MCA) territory initially maintained on aspirin. Eighteen months later, she had recurrence of weakness, for which repeat transthoracic echocardiography (TTE) and re-evaluation of the first TTE demonstrated a hyperechoic membrane spanning the width of the left atrium, clinching the diagnosis of CTS. Despite anticoagulation with apixaban, she was admitted for a third stroke where she succumbed to hospital-acquired pneumonia. Among cases of CTS associated with stroke, anticoagulation and surgery were the main modes of treatment. This case has the longest follow-up and the first to demonstrate failure of antiplatelet therapy and anticoagulation. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  15. Circadian differences in hemisphere-linked spelling proficiencies.

    Science.gov (United States)

    Morton, L L; Diubaldo, D

    1995-03-01

    Male and female adolescents (N = 113) were assigned randomly to spelling instruction in either morning or afternoon groups for a school year. A spelling list (100 words) was administered at the beginning of the school year to obtain a sample of error responses and estimate proficiency. Although equally proficient, subjects tested in the afternoon showed more phonetically inappropriate errors, while those tested in the morning showed more phonetically appropriate errors. This error pattern is viewed as support for a more engaged left hemisphere in the morning. There were no differences on two types of visual errors. Subjects then received instruction in spelling for nine months in either morning or afternoon settings. Time-of-day effects were not evident on the word list and there were too few errors to conduct a posttest error analysis. However, standardized test results for a subgroup revealed that subjects receiving morning instruction made greater gains on phonetically regular words compared to phonetically irregular words--an effect consistent with a circadian-linked higher level of left hemisphere engagement early in the day. The findings are of a pilot nature, but implications for education and further research are discussed.

  16. Hemispheric Division of Labour in Reading

    Science.gov (United States)

    Shillcock, Richard C.; McDonald, Scott A.

    2005-01-01

    We argue that the reading of words and text is fundamentally conditioned by the splitting of the fovea and the hemispheric division of the brain, and, furthermore, that the equitable division of labour between the hemispheres is a characteristic of normal visual word recognition. We report analyses of a representative corpus of the eye fixations…

  17. Heat Stroke

    DEFF Research Database (Denmark)

    Mørch, Sofie Søndergaard; Andersen, Johnny Dohn Holmgren; Bestle, Morten Heiberg

    2017-01-01

    and mortality. This case report describes two Danish patients diagnosed with heat stroke syndrome during a heat wave in the summer of 2014. Both patients were morbidly obese and had several predisposing illnesses. However since heat stroke is a rare condition in areas with temperate climate, they were...... not diagnosed until several days after admittance; hence treatment with cooling was delayed. Both patients were admitted to the intensive care unit, where they were treated with an external cooling device and received treatment for complications. Both cases ended fatally. As global warming continues, more heat...

  18. The language of arithmetic across the hemispheres: An event-related potential investigation.

    Science.gov (United States)

    Dickson, Danielle S; Federmeier, Kara D

    2017-05-01

    Arithmetic expressions, like verbal sentences, incrementally lead readers to anticipate potential appropriate completions. Existing work in the language domain has helped us understand how the two hemispheres differently participate in and contribute to the cognitive process of sentence reading, but comparatively little work has been done with mathematical equation processing. In this study, we address this gap by examining the ERP response to provided answers to simple multiplication problems, which varied both in levels of correctness (given an equation context) and in visual field of presentation (joint attention in central presentation, or biased processing to the left or right hemisphere through contralateral visual field presentation). When answers were presented to any of the visual fields (hemispheres), there was an effect of correctness prior to the traditional N400 timewindow, which we interpret as a P300 in response to a detected target item (the correct answer). In addition to this response, equation answers also elicited a late positive complex (LPC) for incorrect answers. Notably, this LPC effect was most prominent in the left visual field (right hemisphere), and it was also sensitive to the confusability of the wrong answer - incorrect answers that were closely related to the correct answer elicited a smaller LPC. This suggests a special, prolonged role for the right hemisphere during answer evaluation. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. HEMISPHERIC CENTER FOR ENVIRONMENTAL TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian

    1999-10-31

    The Deactivation and Decommissioning (D&D) Technology Assessment Program (TAP) was developed to provide detailed, comparable data for environmental technologies and to disseminate this data to D&D professionals in a manner that will facilitate the review and selection of technologies to perform decontamination and decommissioning. The objectives for this project include the following: Determine technology needs through review of the Site Technology Coordination Group (STCG) information and other applicable websites and needs databases; Perform a detailed review of industries that perform similar activities as those required in D&D operations to identify additional technologies; Define the technology assessment program for characterization and waste management problem sets; Define the data management program for characterization, dismantlement, and waste management problem sets; Evaluate baseline and innovative technologies under standard test conditions at Florida International University's Hemispheric Center for Environmental Technology (FIU-HCET) and other locations and collect data in the areas of performance, cost, health and safety, operations and maintenance, and primary and secondary waste generation; Continue to locate, verify, and incorporate technology performance data from other sources into the multimedia information system; and Develop the conceptual design for a dismantlement technology decision analysis tool for dismantlement technologies.

  20. Confabulations after Bilateral Consecutive Strokes of the Lenticulostriate Arteries

    Directory of Open Access Journals (Sweden)

    Antonio Carota

    2012-03-01

    Full Text Available We describe the case of a 75-year-old woman who manifested persistent confabulations after two consecutive strokes encompassing the area of the lenticulostriate arteries territory on both hemispheres. Findings reported on this rare clinical syndrome suggest that fantastic confabulations and delusional thoughts may arise after bilateral damage of subcortical nonthalamic structures.

  1. Face gender categorization and hemispheric asymmetries: Contrasting evidence from connected and disconnected brains.

    Science.gov (United States)

    Prete, Giulia; Fabri, Mara; Foschi, Nicoletta; Tommasi, Luca

    2016-12-17

    We investigated hemispheric asymmetries in categorization of face gender by means of a divided visual field paradigm, in which female and male faces were presented unilaterally for 150ms each. A group of 60 healthy participants (30 males) and a male split-brain patient (D.D.C.) were asked to categorize the gender of the stimuli. Healthy participants categorized male faces presented in the right visual field (RVF) better and faster than when presented in the left visual field (LVF), and female faces presented in the LVF than in the RVF, independently of the participants' sex. Surprisingly, the recognition rates of D.D.C. were at chance levels - and significantly lower than those of the healthy participants - for both female and male faces presented in the RVF, as well as for female faces presented in the LVF. His performance was higher than expected by chance - and did not differ from controls - only for male faces presented in the LVF. The residual right-hemispheric ability of the split-brain patient in categorizing male faces reveals an own-gender bias lateralized in the right hemisphere, in line with the rightward own-identity and own-age bias previously shown in split-brain patients. The gender-contingent hemispheric dominance found in healthy participants confirms the previously shown right-hemispheric superiority in recognizing female faces, and also reveals a left-hemispheric superiority in recognizing male faces, adding an important evidence of hemispheric imbalance in the field of face and gender perception. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. The Cognitive Neuroplasticity of Reading Recovery following Chronic Stroke: A Representational Similarity Analysis Approach.

    Science.gov (United States)

    Fischer-Baum, Simon; Jang, Ava; Kajander, David

    2017-01-01

    Damage to certain left hemisphere regions leads to reading impairments, at least acutely, though some individuals eventually recover reading. Previous neuroimaging studies have shown a relationship between reading recovery and increases in contralesional and perilesional activation during word reading tasks, relative to controls. Questions remain about how to interpret these changes in activation. Do these changes reflect functional take-over, a reorganization of functions in the damaged brain? Or do they reveal compensatory masquerade or the use of alternative neural pathways to reading that are available in both patients and controls? We address these questions by studying a single individual, CH, who has made a partial recovery of reading familiar words following stroke. We use an fMRI analysis technique, representational similarity analysis (RSA), which allows us to decode cognitive function from distributed patterns of neural activity. Relative to controls, we find that CH shows a shift from visual to orthographic processing in contralesional regions, with a marginally significant result in perilesional regions as well. This pattern supports a contralesional reorganization of orthographic processing following stroke. More generally, these analyses demonstrate how powerful RSA can be for mapping the neural plasticity of language function.

  3. Excitatory deep transcranial magnetic stimulation with H-coil over the right homologous Broca's region improves naming in chronic post-stroke aphasia.

    Science.gov (United States)

    Chieffo, Raffaella; Ferrari, Federico; Battista, Petronilla; Houdayer, Elise; Nuara, Arturo; Alemanno, Federica; Abutalebi, Jubin; Zangen, Abraham; Comi, Giancarlo; Cappa, Stefano F; Leocani, Letizia

    2014-01-01

    The role of the right hemisphere in poststroke aphasia recovery is still controversial and the effects of repetitive transcranial magnetic stimulation (rTMS) over the right homologous Broca's region have been seldom investigated. This study aimed to compare the effect of excitatory, inhibitory, and sham rTMS delivered with H-coil over the right inferior frontal gyrus in chronic aphasic patients. Five right-handed poststroke aphasic patients underwent a picture naming task before and immediately after each of 3 sessions of rTMS: excitatory (10 Hz), inhibitory (1 Hz), and sham rTMS, in random sequence and separated by at least 1 week. Only the excitatory 10-Hz stimulation was associated with a significant improvement in naming performance (P = .043) and was significantly more effective than 1-Hz rTMS (P = .043). A single session of excitatory deep brain rTMS over the right inferior frontal gyrus with H-coil significantly improves naming in right-handed chronic poststroke aphasic patients. This result is in line with the hypothesis of a positive, rather than detrimental, role of the right hemisphere in chronic aphasia due to a left-hemispheric stroke.

  4. Does a combined intervention program of repetitive transcranial magnetic stimulation and intensive occupational therapy affect cognitive function in patients with post-stroke upper limb hemiparesis?

    Directory of Open Access Journals (Sweden)

    Takatoshi Hara

    2016-01-01

    Full Text Available Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS to the contralesional hemisphere and intensive occupational therapy (iOT have been shown to contribute to a significant improvement in upper limb hemiparesis in patients with chronic stroke. However, the effect of the combined intervention program of LF-rTMS and iOT on cognitive function is unknown. We retrospectively investigated whether the combined treatment influence patient's Trail-Making Test part B (TMT-B performance, which is a group of easy and inexpensive neuropsychological tests that evaluate several cognitive functions. Twenty-five patients received 11 sessions of LF-rTMS to the contralesional hemisphere and 2 sessions of iOT per day over 15 successive days. Patients with right- and left-sided hemiparesis demonstrated significant improvements in upper limb motor function following the combined intervention program. Only patients with right-sided hemiparesis exhibited improved TMT-B performance following the combined intervention program, and there was a significant negative correlation between Fugl-Meyer Assessment scale total score change and TMT-B performance. The results indicate the possibility that LF-rTMS to the contralesional hemisphere combined with iOT improves the upper limb motor function and cognitive function of patients with right-sided hemiparesis. However, further studies are necessary to elucidate the mechanism of improved cognitive function.

  5. Left-right cortical asymmetries of regional cerebral blood flow during listening to words

    DEFF Research Database (Denmark)

    Nishizawa, Y; Olsen, T S; Larsen, B

    1982-01-01

    1. Regional cerebral blood flow (rCBF) was measured during rest and during listening to simple words. The xenon-133 intracarotid technique was used and results were obtained from 254 regions of seven right hemispheres and seven left hemispheres. The measurements were performed just after carotid...... of the entire hemisphere. The focal rCBF increases were localized to the superior part of the temporal regions, the prefrontal regions, the frontal eye fields, and the orbitofrontal regions. Significant asymmetries were found in particular in the superior temporal region with the left side showing a more...

  6. Fluctuations of Induced Charge in Hemispherical Detectors

    Science.gov (United States)

    Samedov, V. V.

    2017-12-01

    Detectors with hemispherical geometry are used to eliminate the contribution from the hole component to the signal of a detector based on a compound semiconductor operating at room temperature. In this work, the random process of charge induction on electrodes of a detector with hemispherical geometry is theoretically considered with allowance for capture of electrons by traps. Formulas are obtained for the first two moments of the distribution function for the induced charge on the detector electrodes. These formulas help analyze the contribution of the electron transport in detectors with hemispherical geometry.

  7. Left ventricular performance during psychological stress

    International Nuclear Information System (INIS)

    Young, D.Z.; Massachusetts General Hospital, Boston; Dimsdale, J.E.; Moore, R.H.; Barlai-Kovach, M.; Newell, J.B.; McKusick, K.A.; Boucher, C.A.; Fifer, M.A.; Strauss, H.W.

    1989-01-01

    Left ventricular ejection fraction, systolic blood pressure and plasma norepinephrine were measured in six normotensive and six mildly hypertensive subjects during rest and psychological stress. Compared with rest, 8 of the 12 subjects developed significant changes in ejection fraction (increase in 6, decrease in 2); 10 of 12 subjects developed significant elevations of plasma norepinephrine; and all developed significant increases in systolic blood pressure. When the stress effects were examined for the total group, as opposed to within subjects, there were significant increases in plasma norepinephrine and systolic blood pressure but, interestingly, mean ejection fraction and stroke volume remained unchanged, implying stress led to increased left ventricular contractility. (orig.)

  8. The left visual-field advantage in rapid visual presentation is amplified rather than reduced by posterior-parietal rTMS

    DEFF Research Database (Denmark)

    Verleger, Rolf; Möller, Friderike; Kuniecki, Michal

    2010-01-01

    In the present task, series of visual stimuli are rapidly presented left and right, containing two target stimuli, T1 and T2. In previous studies, T2 was better identified in the left than in the right visual field. This advantage of the left visual field might reflect dominance exerted...... by the right over the left hemisphere. If so, then repetitive transcranial magnetic stimulation (rTMS) to the right parietal cortex might release the left hemisphere from right-hemispheric control, thereby improving T2 identification in the right visual field. Alternatively or additionally, the asymmetry in T2......) either as effective or as sham stimulation. In two experiments, either one of these two factors, hemisphere and effectiveness of rTMS, was varied within or between participants. Again, T2 was much better identified in the left than in the right visual field. This advantage of the left visual field...

  9. Commentary: Left Hand, Right Hand and on the Other Hand

    Science.gov (United States)

    Parslow, Graham R.

    2011-01-01

    It was deeply ingrained in the author from his undergraduate studies of psychology and courses in learning theory that people have a rational left brain and a creative right brain. Learning theory suggested that activities needed to be tailored to develop both hemispheres. Handedness in relation to abilities has been commented on from the 1800s by…

  10. Post-Surgical Language Reorganization Occurs in Tumors of the Dominant and Non-Dominant Hemisphere.

    Science.gov (United States)

    Avramescu-Murphy, M; Hattingen, E; Forster, M-T; Oszvald, A; Anti, S; Frisch, S; Russ, M O; Jurcoane, A

    2017-09-01

    Surgical resection of brain tumors may shift the location of cortical language areas. Studies of language reorganization primarily investigated left-hemispheric tumors irrespective of hemispheric language dominance. We used functional magnetic resonance imaging (fMRI) to investigate how tumors influence post-surgical language reorganization in relation to the dominant language areas. A total of, 17 patients with brain tumors (16 gliomas, one metastasis) in the frontotemporal and lower parietal lobes planned for awake surgery underwent pre-surgical and post-surgical language fMRI. Language activation post-to-pre surgery was evaluated visually and quantitatively on the statistically thresholded images on patient-by-patient basis. Results were qualitatively compared between three patient groups: temporal, with tumors in the dominant temporal lobe, frontal, with tumors in the dominant frontal lobe and remote, with tumors in the non-dominant hemisphere. Post-to-pre-surgical distributions of activated voxels changed in all except the one patient with metastasis. Changes were more pronounced in the dominant hemisphere for all three groups, showing increased number of activated voxels and also new activation areas. Tumor resection in the dominant hemisphere (frontal and temporal) shifted the activation from frontal towards temporal, whereas tumor resection in the non-dominant hemisphere shifted the activation from temporal towards frontal dominant areas. Resection of gliomas in the dominant and in the non-dominant hemisphere induces postsurgical shifts and increase in language activation, indicating that infiltrating gliomas have a widespread influence on the language network. The dominant hemisphere gained most of the language activation irrespective of tumor localization, possibly reflecting recovery of pre-surgical tumor-induced suppression of these activations.

  11. Antiphospholipid Syndrome of Late Onset: A Difficult Diagnosis of a Recurrent Embolic Stroke.

    Science.gov (United States)

    Delgado, Montserrat G; Rodríguez, Sergio; García, Raquel; Sánchez, Pablo; Sáiz, Antonio; Calleja, Sergio

    2015-08-01

    A 77-year-old woman with atrial fibrillation (AF) treated with warfarin had a cortical left middle cerebral artery (MCA) stroke (October 2009, international normalized ratio [INR], 1.6) and a cortical left frontal stroke (October 2011, INR, 1.9). Anticoagulation was adjusted. In October 2011, she had a right frontal stroke (INR, 2.3). Acetylsalicylic acid (ASA) was temporally added to the treatment. In June 2013, she had a left occipital stroke (INR, 2.3). Warfarin was changed to rivaroxaban. In August 2013, she had a right occipital stroke. ASA 100 was added to the treatment. On all occasions, repeated neurovascular studies and echocardiography were normal. Diagnoses were cardioembolic stroke. In November 2013, she was admitted because of a left MCA stroke. A complete blood analysis showed the presence of anticardiolipin, anti-b2-glycoprotein antibodies, and lupus anticoagulant. Primary antiphospholipid syndrome (APS) was later confirmed. APS should be considered in young stroke patients, however is not frequent in stroke patients older than 70 years with several cerebrovascular risk factors. The existence of AF in our patient with several embolic strokes made the cardiembolic etiology likely. Uncommon causes of stroke were not considered despite the repetition of the ischemic events. Thus, a wider etiological study should be made in all patients with a recurrent stroke regardless of age, such as a complete blood analysis including immunology study in order to exclude an APS of late onset. Copyright © 2015. Published by Elsevier Inc.

  12. Memorization of Sequences of Movements of the Right or the Left Hand by Right- and Left-Handers: Vector Coding.

    Science.gov (United States)

    Bobrova, E V; Bogacheva, I N; Lyakhovetskii, V A; Fabinskaja, A A; Fomina, E V

    2017-01-01

    In order to test the hypothesis of hemisphere specialization for different types of information coding (the right hemisphere, for positional coding; the left one, for vector coding), we analyzed the errors of right and left-handers during a task involving the memorization of sequences of movements by the left or the right hand, which activates vector coding by changing the order of movements in memorized sequences. The task was first performed by the right or the left hand, then by the opposite hand. It was found that both'right- and left-handers use the information about the previous movements of the dominant hand, but not of the non-dom" inant one. After changing the hand, right-handers use the information about previous movements of the second hand, while left-handers do not. We compared our results with the data of previous experiments, in which positional coding was activated, and concluded that both right- and left-handers use vector coding for memorizing the sequences of their dominant hands and positional coding for memorizing the sequences of non-dominant hand. No similar patterns of errors were found between right- and left-handers after changing the hand, which suggests that in right- and left-handersthe skills are transferred in different ways depending on the type of coding.

  13. Central auditory processing outcome after stroke in children

    Directory of Open Access Journals (Sweden)

    Karla M. I. Freiria Elias

    2014-09-01

    Full Text Available Objective To investigate central auditory processing in children with unilateral stroke and to verify whether the hemisphere affected by the lesion influenced auditory competence. Method 23 children (13 male between 7 and 16 years old were evaluated through speech-in-noise tests (auditory closure; dichotic digit test and staggered spondaic word test (selective attention; pitch pattern and duration pattern sequence tests (temporal processing and their results were compared with control children. Auditory competence was established according to the performance in auditory analysis ability. Results Was verified similar performance between groups in auditory closure ability and pronounced deficits in selective attention and temporal processing abilities. Most children with stroke showed an impaired auditory ability in a moderate degree. Conclusion Children with stroke showed deficits in auditory processing and the degree of impairment was not related to the hemisphere affected by the lesion.

  14. Dyscalculia, dysgraphia, and left-right confusion from a left posterior peri-insular infarct.

    Science.gov (United States)

    Bhattacharyya, S; Cai, X; Klein, J P

    2014-01-01

    The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI) showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

  15. Dyscalculia, Dysgraphia, and Left-Right Confusion from a Left Posterior Peri-Insular Infarct

    Directory of Open Access Journals (Sweden)

    S. Bhattacharyya

    2014-01-01

    Full Text Available The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

  16. Stroke awareness in Denmark

    DEFF Research Database (Denmark)

    Truelsen, Thomas; Krarup, Lars-Henrik

    2010-01-01

    This is the first study to examine the awareness of major stroke symptoms and stroke risk factors among the general population in Denmark. Early recognition of stroke warning signs and means of reducing stroke occurrence could improve the treatment and prevention of stroke....

  17. The validity and reliability of signs of early infarction on CT in acute ischaemic stroke

    International Nuclear Information System (INIS)

    Dippel, D.W.J.; Du Ry van Beest Holle, M.; Kooten, F. van; Koudstaal, P.J.

    2000-01-01

    It has been suggested that subtle signs of early cerebral infarction on CT are important indicators of outcome and of the effect of thrombolytic treatment in acute ischaemic stroke. We studied these signs prospectively, in 260 patients with an anterior circulation stroke from a European-Australian randomised trial of lubeluzole in acute ischaemic stroke. Interobserver reliability was assessed by means of the χ statistic. The validity of the early signs was assessed by comparing the assessments of the first CT with another CT at 1 week after the onset of stroke, and with stroke outcome at 12 weeks. Each initial CT study was assessed by two of a group of five reviewers, who were blinded to each other's assessments and to the findings on the follow-up CT. The images were assessed twice, once without clinical information and again after disclosure of the side (left or right hemisphere) of the lesion. All reviewers were experienced clinicians with a special interest and training in vascular neurology and CT. The median time between stroke onset and the first CT was 3.2 h; 59 % of the patients were imaged within 3 h and 77 % within 6 h. More than half of the patients (52 %) had a large middle cerebral artery territory (MCA) infarct on follow-up CT. Chance-adjusted interobserver agreement (χ) for any early infarct was 0.27 (95 % confidence interval (CI): 0.15 to 0.39). Agreement (χ) on the extent of a middle cerebral artery (MCA) infarct and on the indication for treatment with recombinant tissue plasminogen activator (rt-PA) was fair: 0.37 and 0.35, respectively. Patients with early signs of an infarct of more than 1/3 of the MCA territory were more likely to have a large MCA infarct on follow-up CT (odds ratio 5.7, 95 % confidence interval 2.8-11.5); the positive and negative predictive value of these signs was 81 % and 57 %, respectively. Chance-adjusted interobserver agreement on early, subtle signs of a large MCA territory infarct on CT by neurologists was thus no

  18. Dyslexia Treated by Hemisphere Stimulation Technic

    OpenAIRE

    J Gordon Millichap

    1997-01-01

    Results of treatment of severe dyslexia in 80 children, ages 6 to 15 years, using hemisphere stimulation technics, are reported from the outpatient Department for Dyslexia, Child Psychiatric Center, Paedological Institute, Amsterdam, The Netherlands.

  19. Phylogeography of Burkholderia pseudomallei Isolates, Western Hemisphere.

    Science.gov (United States)

    Gee, Jay E; Gulvik, Christopher A; Elrod, Mindy G; Batra, Dhwani; Rowe, Lori A; Sheth, Mili; Hoffmaster, Alex R

    2017-07-01

    The bacterium Burkholderia pseudomallei causes melioidosis, which is mainly associated with tropical areas. We analyzed single-nucleotide polymorphisms (SNPs) among genome sequences from isolates of B. pseudomallei that originated in the Western Hemisphere by comparing them with genome sequences of isolates that originated in the Eastern Hemisphere. Analysis indicated that isolates from the Western Hemisphere form a distinct clade, which supports the hypothesis that these isolates were derived from a constricted seeding event from Africa. Subclades have been resolved that are associated with specific regions within the Western Hemisphere and suggest that isolates might be correlated geographically with cases of melioidosis. One isolate associated with a former World War II prisoner of war was believed to represent illness 62 years after exposure in Southeast Asia. However, analysis suggested the isolate originated in Central or South America.

  20. Stroke rehabilitation.

    Science.gov (United States)

    Langhorne, Peter; Bernhardt, Julie; Kwakkel, Gert

    2011-05-14

    Stroke is a common, serious, and disabling global health-care problem, and rehabilitation is a major part of patient care. There is evidence to support rehabilitation in well coordinated multidisciplinary stroke units or through provision of early supported provision of discharge teams. Potentially beneficial treatment options for motor recovery of the arm include constraint-induced movement therapy and robotics. Promising interventions that could be beneficial to improve aspects of gait include fitness training, high-intensity therapy, and repetitive-task training. Repetitive-task training might also improve transfer functions. Occupational therapy can improve activities of daily living; however, information about the clinical effect of various strategies of cognitive rehabilitation and strategies for aphasia and dysarthria is scarce. Several large trials of rehabilitation practice and of novel therapies (eg, stem-cell therapy, repetitive transcranial magnetic stimulation, virtual reality, robotic therapies, and drug augmentation) are underway to inform future practice. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Cigarette smoking is an independent risk factor for post-stroke delirium.

    Science.gov (United States)

    Lim, Tae Sung; Lee, Jin Soo; Yoon, Jung Han; Moon, So Young; Joo, In Soo; Huh, Kyoon; Hong, Ji Man

    2017-03-23

    Post-stroke delirium is a common problem in the care of stroke patients, and is associated with longer hospitalization, high short-term mortality, and an increased need for long-term care. Although post-stroke delirium occurs in approximately 10 ~ 30% of patients, little is known about the risk factors for post-stroke delirium in patients who experience acute stroke. A total of 576 consecutive patients who experienced ischemic stroke (mean age, 65.2 years; range, 23-93 years) were screened for delirium over a 2-year period in an acute stroke care unit of a tertiary referral hospital. We screened for delirium using the Confusion Assessment Method. Once delirium was suspected, we evaluated the symptoms using the Korean Version of the Delirium Rating Scale-Revised-98. Neurological deficits were assessed using the National Institutes of Health Stroke Scale at admission and discharge, and functional ability was assessed using the Barthel Index and modified Rankin Scale at discharge and 3 months after discharge. Thirty-eight (6.7%) patients with stroke developed delirium during admission to the acute stroke care unit. Patients with delirium were significantly older (70.6 vs. 64.9 years of age, P = .001) and smoked cigarettes more frequently (40% vs. 24%, P = .033) than patients without delirium. In terms of clinical features, the delirium group experienced a significantly higher rate of major hemispheric stroke (55% vs. 26%, P delirium were older age, history of cigarette smoking, and major hemispheric stroke. Abrupt cessation of cigarette smoking may be a risk factor for post-stroke delirium in ischemic stroke patients. The development of delirium after stroke is associated with worse outcome and longer hospitalization.

  2. Northern Hemisphere forcing of Southern Hemisphere climate during the last deglaciation.

    Science.gov (United States)

    He, Feng; Shakun, Jeremy D; Clark, Peter U; Carlson, Anders E; Liu, Zhengyu; Otto-Bliesner, Bette L; Kutzbach, John E

    2013-02-07

    According to the Milankovitch theory, changes in summer insolation in the high-latitude Northern Hemisphere caused glacial cycles through their impact on ice-sheet mass balance. Statistical analyses of long climate records supported this theory, but they also posed a substantial challenge by showing that changes in Southern Hemisphere climate were in phase with or led those in the north. Although an orbitally forced Northern Hemisphere signal may have been transmitted to the Southern Hemisphere, insolation forcing can also directly influence local Southern Hemisphere climate, potentially intensified by sea-ice feedback, suggesting that the hemispheres may have responded independently to different aspects of orbital forcing. Signal processing of climate records cannot distinguish between these conditions, however, because the proposed insolation forcings share essentially identical variability. Here we use transient simulations with a coupled atmosphere-ocean general circulation model to identify the impacts of forcing from changes in orbits, atmospheric CO(2) concentration, ice sheets and the Atlantic meridional overturning circulation (AMOC) on hemispheric temperatures during the first half of the last deglaciation (22-14.3 kyr BP). Although based on a single model, our transient simulation with only orbital changes supports the Milankovitch theory in showing that the last deglaciation was initiated by rising insolation during spring and summer in the mid-latitude to high-latitude Northern Hemisphere and by terrestrial snow-albedo feedback. The simulation with all forcings best reproduces the timing and magnitude of surface temperature evolution in the Southern Hemisphere in deglacial proxy records. AMOC changes associated with an orbitally induced retreat of Northern Hemisphere ice sheets is the most plausible explanation for the early Southern Hemisphere deglacial warming and its lead over Northern Hemisphere temperature; the ensuing rise in atmospheric CO(2

  3. Multiple Strokes

    Directory of Open Access Journals (Sweden)

    Obododimma Oha

    2008-12-01

    Full Text Available This poem playfully addresses the slippery nature of linguistic signification, employing humour and sarcasm in presenting a wide range of human experience. It ironical twists -- and "strokes" (read ambiguously as both a giving a punishment and erotic pleasuring -- move from the naming of location through international discourse of capital to the crumbling relationships between nation states. It reading of the signs of language is tied to the unease and fracture in cultural and political experience.

  4. Directional information flows between brain hemispheres across waking, non-REM and REM sleep states: an EEG study.

    Science.gov (United States)

    Bertini, Mario; Ferrara, Michele; De Gennaro, Luigi; Curcio, Giuseppe; Moroni, Fabio; Babiloni, Claudio; Infarinato, Francesco; Rossini, Paolo Maria; Vecchio, Fabrizio

    2009-03-30

    The present electroencephalographic (EEG) study evaluated the hypothesis of a preferred directionality of communication flows between brain hemispheres across 24 h (i.e., during the whole daytime and nighttime), as an extension of a recent report showing changes in preferred directionality from pre-sleep wake to early sleep stages. Scalp EEGs were recorded in 10 normal volunteers during daytime wakefulness (eyes closed; first period: from 10:00 to 13:00 h; second period: from 14:00 to 18:00 h; third period: from 19:00 to 22:00 h) and nighttime sleep (four NREM-REM cycles). EEG rhythms of interest were delta (1-4 Hz), theta (5-7 Hz), alpha (8-11 Hz), sigma (12-15 Hz) and beta (16-28 Hz). The direction of the inter-hemispheric information flow was evaluated by computing the directed transfer function (DTF) from these EEG rhythms. Inter-hemispheric directional flows varied as a function of the state of consciousness (wake, NREM sleep, REM sleep) and in relation to different cerebral areas. During the daytime, alpha and beta rhythms conveyed inter-hemispheric signals with preferred Left-to-Right hemisphere direction in parietal and central areas, respectively. During the NREM sleep periods of nighttime, the direction of inter-hemispheric DTF information flows conveyed by central beta rhythms was again preponderant from Left-to-Right hemisphere in the stage 2, independent of cortical areas. No preferred direction emerged across the REM periods. These results support the hypothesis that specific directionality of communication flows between brain hemispheres is associated with wakefulness, NREM (particularly stage 2) and REM states during daytime and nighttime. They also reinforce the suggestive hypothesis of a relationship between inter-hemispheric directionality of EEG functional coupling and frequency of the EEG rhythms.

  5. Ipsilesional deficit of selective attention in left homonymous hemianopia and left unilateral spatial neglect.

    Science.gov (United States)

    Chokron, Sylvie; Peyrin, Carole; Perez, Céline

    2018-03-15

    Patients with homonymous hemianopia may present a subtle ipsilesional deficit, recently referred to as 'sightblindness' in addition to the contralesional visual field defect. We recently demonstrated that this deficit could be worse in right brain-damaged patients with left hemianopia than in left brain-damaged patients with right hemianopia, confirming right hemisphere dominance for visuo-spatial and attentional capacities. In the present study we investigate whether this ipsilesional deficit could be attentional in nature and to what extent it is comparable in right brain-damaged (RBD) patients with left hemianopia and in RBD patients with left neglect. The study was also conducted in RBD patients with neither left hemianopia nor left neglect signs in order to test if a right hemisphere lesion per se could be responsible for subtle ipsilesional attentional deficit. To reach this aim, we tested selective attentional capacities in both visual fields of 10 right brain-damaged patients with left neglect (LN), 8 right brain-damaged patients with left homonymous hemianopia (LHH), 8 right brain-damaged patients with no signs of left neglect or left hemianopia (RBD controls), and 17 healthy age-matched participants (Normal controls). A lateralized letter-detection task was used to test if right-brain damaged patients with LN or LH may present a deficit of selective attention in their right, ipsilesional visual field, in comparison to Normal and RBD controls. Participants were asked to detect a target letter in either a single large stimulus (low attentional load) or a small stimulus surrounded by flankers (high attentional load). Stimuli were displayed either in the left or in the right visual field. Accuracy and reaction times were recorded. Results on accuracy showed that both LN and LH patients exhibited lower correct responses than Normal controls in their ipsilesional right visual field, suggesting an attentional deficit in their ipsilesional, supposed healthy

  6. Preventing Stroke Deaths

    Science.gov (United States)

    ... die within minutes. Strokes happen more in some populations and geographic areas. Stroke death declines have stalled in 3 out of every 4 states. Blacks have the highest stroke death rates among all ...

  7. Two Kinds of Stroke

    Science.gov (United States)

    ... Issue Past Issues Special Section Two Kinds of Stroke Past Issues / Summer 2007 Table of Contents For ... are often a warning sign for future strokes. Stroke Can Affect Anyone Award-winning actress Julie Harris ...

  8. Healthy Living after Stroke

    Science.gov (United States)

    ... Stories Stroke Heroes Among Us Healthy Living After Stroke Nutrition Good nutrition is one way to reduce ... the hospital. Thank goodness, she did. Subscribe to Stroke Connection Get quarterly digital issues plus our monthly ...

  9. Understanding Life After Stroke

    OpenAIRE

    Hjelmblink, Finn

    2008-01-01

    Stroke is an acute, neurological dysfunction of vascular origin with sudden occurrence and it influences physical, cognitive and psychological functions. Initial treatment aims at eliminating or reducing the brain damage. Soon, however, the influence of the stroke on the entire life of stroke survivors has to be considered. This thesis explores the meaning of life after stroke to 19 elderly stroke survivors during the first year post stroke. Survivors were interviewed twice and the interviews...

  10. Difficulty Swallowing After Stroke (Dysphagia)

    Science.gov (United States)

    ... Simple Techniques Can Help Memory after a Stroke Self-Esteem after Stroke Cognitive Challenges After Stroke Depression Trumps ... spasticity), fatigue and more. Let's Talk About Stroke Fact Sheets Our stroke fact sheets cover treatments, recovery, ...

  11. Structural changes induced by daily music listening in the recovering brain after middle cerebral artery stroke: a voxel-based morphometry study.

    Science.gov (United States)

    Särkämö, Teppo; Ripollés, Pablo; Vepsäläinen, Henna; Autti, Taina; Silvennoinen, Heli M; Salli, Eero; Laitinen, Sari; Forsblom, Anita; Soinila, Seppo; Rodríguez-Fornells, Antoni

    2014-01-01

    Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery stroke. Extending this study, a voxel-based morphometry (VBM) analysis utilizing cost function masking was performed on the acute and 6-month post-stroke stage structural magnetic resonance imaging data of the patients (n = 49) who either listened to their favorite music [music group (MG), n = 16] or verbal material [audio book group (ABG), n = 18] or did not receive any listening material [control group (CG), n = 15] during the 6-month recovery period. Although all groups showed significant gray matter volume (GMV) increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG), right medial SFG] and limbic areas [left ventral/subgenual anterior cingulate cortex (SACC) and right ventral striatum (VS)] in patients with left hemisphere damage in which the GMV increases were larger in the MG than in the ABG and in the CG. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioral recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.

  12. Structural changes induced by daily music listening in the recovering brain after middle cerebral artery stroke: a voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Teppo eSärkämö

    2014-04-01

    Full Text Available Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery (MCA stroke. Extending this study, a voxel-based morphometry (VBM analysis utilizing cost-function masking was performed on the acute and 6-month post-stroke stage structural MRI data of the patients (n = 49 who either listened to their favourite music (music group, n = 16 or verbal material (audio book group, n = 18 or did not receive any listening material (control group, n = 15 during the 6-month recovery period. Although all groups showed significant grey matter volume (GMV increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG, right medial SFG] and limbic areas [left ventral / subgenual anterior cingulate cortex (SACC and right ventral striatum (VS] in patients with left hemisphere damage in which the GMV increases were larger in the music group than in the audio book and control groups. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioural recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.

  13. Right hemisphere control of visuospatial attention in near space.

    Science.gov (United States)

    Longo, Matthew R; Trippier, Sarah; Vagnoni, Eleonora; Lourenco, Stella F

    2015-04-01

    Traditionally, the right cerebral hemisphere has been considered to be specialized for spatial attention and orienting. A large body of research has demonstrated dissociable representations of the near space immediately surrounding the body and the more distance far space. In this study, we investigated whether right hemisphere activations commonly reported for tasks involving spatial attention (such as the line bisection and landmark tasks) are specific to stimuli presented in near space. In separate blocks of trials, participants judged either whether a vertical transector was to the left or right of the centre of a line (landmark task) or whether the line was red or blue (colour task). Stimuli were seen from four distances (30, 60, 90, 120 cm). We used EEG to measure an ERP component (the 'line-bisection effect') specific to the direction of spatial attention (i.e., landmark minus colour). Consistent with previous results, spatial attention produced a right-lateralized negativity over occipito-parietal channels. The magnitude of this negativity was inversely related to viewing distance, being largest in near space and reduced in far space. These results suggest that the right occipito-temporal cortex may be specialized not just for the orientation of spatial attention generally, but specifically for orienting attention in the near space immediately surrounding the body. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. MRI-Based Neuroanatomical Predictors of Dysphagia, Dysarthria, and Aphasia in Patients with First Acute Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Heather L. Flowers

    2017-02-01

    Full Text Available Background: Due to the high post-stroke frequency of dysphagia, dysarthria, and aphasia, we developed comprehensive neuroanatomical, clinical, and demographic models to predict their presence after acute ischemic stroke. Methods: The sample included 160 randomly selected first-ever stroke patients with confirmed infarction on magnetic resonance imaging from 1 tertiary stroke center. We documented acute lesions within 12 neuroanatomical regions and their associated volumes. Further, we identified concomitant chronic brain disease, including atrophy, white matter hyperintensities, and covert strokes. We developed predictive models using logistic regression with odds ratios (OR and their 95% confidence intervals (95% CI including demographic, clinical, and acute and chronic neuroanatomical factors. Results: Predictors of dysphagia included medullary (OR 6.2, 95% CI 1.5–25.8, insular (OR 4.8, 95% CI 2.0–11.8, and pontine (OR 3.6, 95% CI 1.2–10.1 lesions, followed by brain atrophy (OR 3.0, 95% CI 1.04–8.6, internal capsular lesions (OR 2.9, 95% CI 1.2–6.6, and increasing age (OR 1.4, 95% CI 1.1–1.8. Predictors of dysarthria included pontine (OR 7.8, 95% CI 2.7–22.9, insular (OR 4.5, 95% CI 1.8–11.4, and internal capsular (OR 3.6, 95% CI 1.6–7.9 lesions. Predictors of aphasia included left hemisphere insular (OR 34.4, 95% CI 4.2–283.4, thalamic (OR 6.2, 95% CI 1.6–24.4, and cortical middle cerebral artery (OR 4.7, 95% CI 1.5–14.2 lesions. Conclusion: Predicting outcomes following acute stroke is important for treatment decisions. Determining the risk of major post-stroke impairments requires consideration of factors beyond lesion localization. Accordingly, we demonstrated interactions between localized and global brain function for dysphagia and elucidated common lesion locations across 3 debilitating impairments.

  15. RISK FACTORS FOR STROKE AND USE OF ...

    African Journals Online (AJOL)

    Kateee

    2003-04-04

    Apr 4, 2003 ... Objective: To review risk factors for stroke and the use of echocardiography in its diagnosis. ... embolism(5,18). Intra-cardiac thrombosis: This occurs in the setting of post myocardial infarction particularly in the anterior cardiac area (19). AC with INR .... of left ventricular thrombi in patients with acute anterior.

  16. Transfer of training effects in stroke patients with apraxia: an exploratory study.

    Science.gov (United States)

    Geusgens, Chantal; van Heugten, Caroline; Donkervoort, Mireille; van den Ende, Els; Jolles, Jelle; van den Heuvel, Wim

    2006-04-01

    The goal of the present study was to examine the transfer of the effects of cognitive strategy training for stroke patients with apraxia from trained to non-trained tasks. In strategy training, the occurrence of transfer is expected as the training programme is aimed, not at relearning specific tasks, but at teaching patients new ways to handle the problems resulting from the impairment. Exploratory analyses were conducted on data previously collected in a randomised controlled trial on the efficacy of the strategy training. A total of 113 left hemisphere stroke patients were randomly assigned to a strategy training group and a group receiving occupational therapy as usual. Assessment of apraxia, motor functioning and activities of daily living (ADL) took place at baseline, after an eight-week treatment period, and five months after baseline. The primary outcome measure consisted of standardised ADL observations of trained and non-trained tasks. The analyses showed that in both treatment groups, the scores on the ADL observations for non-trained tasks improved significantly after eight weeks of training as compared with the baseline score. Change scores of non-trained activities were larger in the strategy training group as compared with the usual treatment group. By using previously collected data we are able to illustrate the potential transfer of treatment effects in a large sample of stroke patients. We found indications for the occurrence of transfer, although the study was not originally designed for the purpose of evaluating transfer. Therefore these results are worth exploring more profoundly. We will further investigate our preliminary conclusions in a new prospective study which is specifically designed to examine the transfer of training effects.

  17. Differences between left- and right-sided neglect revisited : A large cohort study across multiple domains

    NARCIS (Netherlands)

    Ten Brink, Antonia F.; Verwer, Jurre H.; Biesbroek, J. Matthijs; Visser-Meily, Johanna M. A.; Nijboer, Tanja C.W.

    2017-01-01

    Unilateral spatial neglect (USN) is a syndrome that can occur after right- and left-hemisphere damage. It is generally accepted that left-sided USN is more severe than right-sided USN. Evidence for such a difference in other domains is lacking. Primary aims were to compare frequency, severity,

  18. Effects of daily noise on fetuses and cerebral hemisphere specialization in children

    Science.gov (United States)

    Ando, Y.

    1988-12-01

    This paper first provides an overview of work by the author and colleagues on effects of noise on fetuses demonstrating growth inhibition. As a second issue, the effects of daily noise on the mental abilities of children are discussed in relation to task specification of cerebral hemispheres. Two different types of mental tasks were given to a total of 1286 children (7-10 years old) who live in a noisy area around an international airport or in a neighbouring quiet area, under conditions of no sound, jet-plane noise stimulus and music stimulus. In the quiet neighborhood, results may support a model that noise and calculation tasks are separately processed in the right and left cerebral hemisphere, respectively. Music perception and calculation are considered to be processed one after the other in the left hemisphere. In the pattern search task used as the right hemispheric task, no significant differences appeared under either stimulus sound, with the exception of a slight interference observed in the noise group. In the noisy living area, however, effects of temporary sound on mental tasks appeared to be quite different from the first-mentioned results. These facts suggest that daily noise affects the development of cerebral specialization of growing children. As little is known about effects of noise on growing children, it is recommended that international cooperation be initiated to establish the need for and conditions of healthy sound environments.

  19. Studying hemispheric lateralization during a Stroop task through near-infrared spectroscopy-based connectivity

    Science.gov (United States)

    Zhang, Lei; Sun, Jinyan; Sun, Bailei; Luo, Qingming; Gong, Hui

    2014-05-01

    Near-infrared spectroscopy (NIRS) is a developing and promising functional brain imaging technology. Developing data analysis methods to effectively extract meaningful information from collected data is the major bottleneck in popularizing this technology. In this study, we measured hemodynamic activity of the prefrontal cortex (PFC) during a color-word matching Stroop task using NIRS. Hemispheric lateralization was examined by employing traditional activation and novel NIR