Interaction between spatial neglect and attention deficit in patients with right hemisphere damage

Cortex ◽  
2021 ◽  
Author(s):  
Yusaku Takamura ◽  
Shintaro Fujii ◽  
Satoko Ohmatsu ◽  
Koki Ikuno ◽  
Kohei Tanaka ◽  
...  
Keyword(s):  
Attention Deficit ◽  
Right Hemisphere ◽  
Spatial Neglect ◽  
Right Hemisphere Damage

scholarly journals A kinematic analysis of distractor interference effects during visually guided action in spatial neglect

2001 ◽  
Vol 7 (3) ◽  
pp. 334-343 ◽  
Author(s):  
LOUISE A. CORBEN ◽  
JASON B. MATTINGLEY ◽  
JOHN L. BRADSHAW
Keyword(s):  
Right Hemisphere ◽  
Spatial Neglect ◽  
Visually Guided ◽  
Interference Effects ◽  
Double Step ◽  
Central Target ◽  
Right Hemisphere Damage ◽  
Visuomotor System ◽  
Visually Guided Action ◽  
Terminal Guidance

Patients with left spatial neglect following right hemisphere damage may show anomalies in ipsilesional-limb movements directed to targets on their affected side, in addition to their characteristic perceptual deficits. In this study we examined the extent to which visually guided movements made by neglect patients are susceptible to interference from concurrent visual distractors on the contralesional or ipsilesional side of a designated target. Eleven right hemisphere patients with visual neglect, plus 11 matched healthy controls, performed a double-step movement task upon a digitizing tablet, using their ipsilesional hand to respond. On each double-step trial the first component of the movement was cued to a common central target, whereas the second component was cued unpredictably to a target on either the contralesional or ipsilesional side. On separate trials lateral targets either appeared alone or together with a concurrent distractor in an homologous location in the opposite hemispace. In addition to being significantly slower and more error prone than controls, neglect patients also exhibited a number of interference effects from ipsilesional distractors. They often failed to move to left targets in the presence of a right-sided distractor, or else they moved to the distractor itself rather than to a contralesional target. The initial accelerative phase of their movements to contralesional targets tended to be interrupted prematurely, and they spent significantly more time in the terminal guidance phase of movements to contralesional targets in the presence of an ipsilesional distractor. In contrast, contralesional distractors had little effect on patients' movements to ipsilesional targets. We conclude that right hemisphere damage induces a competitive bias that favors actions to ipsilesional targets. This bias affects multiple stages of processing within the visuomotor system, from initial programming through to the final stages of terminal guidance. (JINS, 2001, 7, 334–343)

Computing an Average When Part of the Population Is Not Perceived

2015 ◽  
Vol 27 (7) ◽  
pp. 1397-1411 ◽  
Author(s):  
Marina Pavlovskaya ◽  
Nachum Soroker ◽  
Yoram S. Bonneh ◽  
Shaul Hochstein
Keyword(s):  
Visual Information ◽  
Right Hemisphere ◽  
Statistical Processing ◽  
Orienting Response ◽  
Statistical Properties ◽  
Spatial Neglect ◽  
Visual Scene ◽  
Right Hemisphere Damage ◽  
Visual Tasks ◽  
Average Size

The syndrome of unilateral spatial neglect (USN) after right-hemisphere damage is characterized by failure of salient left-sided stimuli to activate an orienting response, attract attention, and gain access to conscious awareness. The explicit failure processing left-sided visual information is not uniform, however, and patients seem to be more successful performing certain visual tasks than others. The source of this difference is still not clear. We focus on processing of visual scene statistical properties, asking whether, in computing the average size of an array of objects, USN patients give appropriate weight to objects on the left; disregard left-side objects entirely; or assign them an intermediate, lower weight, in accord with their tendency to neglect these objects. The interest in testing this question stems from a series of studies in healthy individuals that led Chong and Treisman [Chong, S. C., & Treisman, A. Statistical processing: Computing the average size in perceptual groups. Vision Research, 45, 891–900, 2005a; Chong, S. C., & Treisman, A. Attentional spread in the statistical processing of visual displays. Perception & Psychophysics, 67, 1–13, 2005b] to propose that processing of statistical properties (like the average size of visual scene elements) is carried out in parallel, with no need for serial allocation of focal attention to the different scene elements. Our results corroborate this suggestion, showing that objects in the left (“neglected”) hemispace contribute to average size computation, despite a marked imbalance in spatial distribution of attention, which leads to a reduced weight of left-side elements in the averaging computation. This finding sheds light on the nature of the impairment in USN and on basic mechanisms underlying statistical processing in vision. We confirm that statistical processing depends mainly on spread-attention mechanisms, which are largely spared in USN.

Neuropsychological mechanisms of left unilateral spatial neglect associated with right hemisphere damage

1994 ◽  
Vol 1 ◽  
pp. 255
Author(s):  
T. Kashiwagi ◽  
A. Kashiwagi ◽  
T. Nishikawa ◽  
H. Tanabe ◽  
J. Okuda ◽  
...  
Keyword(s):  
Right Hemisphere ◽  
Spatial Neglect ◽  
Unilateral Spatial Neglect ◽  
Right Hemisphere Damage ◽  
Neuropsychological Mechanisms

Anosognosia for Hemiplegia in Stroke Rehabilitation

2001 ◽  
Vol 15 (3) ◽  
pp. 213-222 ◽  
Author(s):  
Adina Hartman-Maeir ◽  
Nachum Soroker ◽  
Noomi Katz
Keyword(s):  
Right Hemisphere ◽  
Significant Risk ◽  
Spatial Neglect ◽  
Implicit Measure ◽  
Safety Measures ◽  
Attentional Deficits ◽  
Temporal Lobes ◽  
Right Hemisphere Damage ◽  
Underlying Mechanisms

Objective: The purpose of this study was to investigate anosognosia for hemiple gia (AHP) in the rehabilitation phase after onset of stroke. Methods: Forty-six hemi plegic stroke patients, 29 with right hemisphere damage (RHD) and 17 with left hemi sphere damage (LHD) were evaluated ∼1 month after onset of stroke. Anosognosia was evaluated with an implicit measure designed to assess anosognosic behaviors (choosing between unimanual and bimanual tasks), in addition to a traditional ex plicit verbal measure. Results: AHP was found m 28% of the RHD and 24% of the LHD group. The majority of patients with AHP in the RHD group had large lesions involving the frontal, parietal, or temporal lobes and had coexisting sensory deficits and unilateral spatial neglect, whereas the LHD patients with AHP had predominantly small subcortical lesions and no sensory or attentional deficits. The functional out comes of AHP patients in both hemisphere groups revealed their inability to retain safety measures at discharge from rehabilitation (p < 0.036) and their need for assis tance in basic and instrumental activities of daily living at follow-up. Conclusions: AHP presents a significant risk for negative functional outcome in stroke rehabilita tion. The underlying mechanisms of AHP may be different for left and right hemi sphere patients, therefore requiring different intervention approaches. Key Words: Anosognosia—Cerebrovascular accident—Rehabilitation outcome.

Verbal comprehension deficits after right hemisphere damage

1980 ◽  
Vol 1 (3) ◽  
pp. 279-294 ◽  
Author(s):  
Daniel B. Hier ◽  
Joni Kaplan
Keyword(s):  
Educational Attainment ◽  
Sentence Comprehension ◽  
Right Hemisphere ◽  
Vocabulary Test ◽  
Verbal Comprehension ◽  
Visuospatial Deficits ◽  
Control Subjects ◽  
Right Hemisphere Damage ◽  
The Right ◽  
Grammatical Sentence

ABSTRACTWe have compared the verbal comprehension abilities of 34 right hemisphere damaged patients to 16 hospitalized control subjects of comparable age and educational attainment. The right hemisphere damaged patients performed as well as the control subjects on a vocabulary test, but were impaired in their ability to interpret proverbs and comprehend logico-grammatical sentences. Impairment on the proverbs test was the result of a decrease in the number of abstract interpretations, whereas impairment on the logico-grammatical sentence comprehension test was related to difficultes in grasping spatial and passive relationships. These comprehension impairments tended to correlate with visuospatial deficits and hemianopia, but not with the degree of hemiparesis or the presence of sensory extinction. Patients with anterior right hemisphere damage performed better on the logico-grammatical sentence conprehension test than patients with posterior damage. A variety of factors probably contribute to these verbal deficits including impaired intellect, inattention, an inability to grasp spatial relationships, and difficulties in manipulating the inner schemata of language.

Unwanted reflex-like saccades in visual extinction patients

1999 ◽  
Vol 22 (4) ◽  
pp. 683-683 ◽  
Author(s):  
Alessandra Fanini ◽  
Carlo Alberto Marzi
Keyword(s):  
Reaction Time ◽  
Right Hemisphere ◽  
Visual Stimuli ◽  
Reaction Time Task ◽  
Time Task ◽  
Right Hemisphere Damage ◽  
Visual Extinction ◽  
Manual Reaction Time

We studied patients with left visual extinction following right hemisphere damage in a simple manual reaction time task using brief visual stimuli. With unilateral lateralized stimuli the patients showed a high proportion of unwanted, reflex-like saccades to either side of stimulation. In contrast, with bilateral stimuli there was an overall decrease in the proportion of unwanted saccades, and the vast majority of them were directed toward the ipsilesional side. The implications of these results for the Findlay & Walker model are discussed.

Disturbance of rhythm sense following right hemisphere damage

1990 ◽  
Vol 28 (12) ◽  
pp. 1317-1323 ◽  
Author(s):  
Wolfgang Fries ◽  
Andrew A. Swihart
Keyword(s):  
Right Hemisphere ◽  
Right Hemisphere Damage

Brain Network Dysfunction in Poststroke Delirium and Spatial Neglect: An fMRI Study

Stroke ◽  
2021 ◽  
Author(s):  
Olga Boukrina ◽  
Mateusz Kowalczyk ◽  
Yury Koush ◽  
Yekyung Kong ◽  
A.M. Barrett
Keyword(s):  
Right Hemisphere ◽  
Functional Neuroimaging ◽  
Brain Network ◽  
Spatial Neglect ◽  
Stroke Recovery ◽  
Network Activity ◽  
Brain Disorder ◽  
Fmri Study ◽  
The Right ◽  
Right Hemisphere Stroke

Background and Purpose: Delirium, an acute reduction in cognitive functioning, hinders stroke recovery and contributes to cognitive decline. Right-hemisphere stroke is linked with higher delirium incidence, likely, due to the prevalence of spatial neglect (SN), a right-brain disorder of spatial processing. This study tested if symptoms of delirium and SN after right-hemisphere stroke are associated with abnormal function of the right-dominant neural networks specialized for maintaining attention, orientation, and arousal. Methods: Twenty-nine participants with right-hemisphere ischemic stroke undergoing acute rehabilitation completed delirium and SN assessments and functional neuroimaging scans. Whole-brain functional connectivity of 4 right-hemisphere seed regions in the cortical-subcortical arousal and attention networks was assessed for its relationship to validated SN and delirium severity measures. Results: Of 29 patients, 6 (21%) met the diagnostic criteria for delirium and 16 (55%) for SN. Decreased connectivity of the right basal forebrain to brain stem and basal ganglia predicted more severe SN. Increased connectivity of the arousal and attention network regions with the parietal, frontal, and temporal structures in the unaffected hemisphere was also found in more severe delirium and SN. Conclusions: Delirium and SN are associated with decreased arousal network activity and an imbalance of cortico-subcortical hemispheric connectivity. Better understanding of neural correlates of poststroke delirium and SN will lead to improved neuroscience-based treatment development for these disorders.

scholarly journals Right hemisphere damage: Communication processing in adults evaluated by the Brazilian Protocole MEC - Bateria MAC

2007 ◽  
Vol 1 (3) ◽  
pp. 266-275 ◽  
Author(s):  
Rochele Paz Fonseca ◽  
Jandyra Maria Guimarães Fachel ◽  
Márcia Lorena Fagundes Chaves ◽  
Francéia Veiga Liedtke ◽  
Maria Alice de Mattos Pimenta Parente
Keyword(s):  
Right Hemisphere ◽  
Damage Effect ◽  
Control Group ◽  
Clinical Group ◽  
Conversational Discourse ◽  
Lexical Semantic ◽  
Right Hemisphere Damage ◽  
Right Brain ◽  
Communication Processes ◽  
Brazilian Version

Abstract Right-brain-damaged individuals may present discursive, pragmatic, lexical-semantic and/or prosodic disorders. Objective: To verify the effect of right hemisphere damage on communication processing evaluated by the Brazilian version of the Protocole Montréal d'Évaluation de la Communication (Montreal Communication Evaluation Battery) - Bateria Montreal de Avaliação da Comunicação, Bateria MAC, in Portuguese. Methods: A clinical group of 29 right-brain-damaged participants and a control group of 58 non-brain-damaged adults formed the sample. A questionnaire on sociocultural and health aspects, together with the Brazilian MAC Battery was administered. Results: Significant differences between the clinical and control groups were observed in the following MAC Battery tasks: conversational discourse, unconstrained, semantic and orthographic verbal fluency, linguistic prosody repetition, emotional prosody comprehension, repetition and production. Moreover, the clinical group was less homogeneous than the control group. Conclusions: A right-brain-damage effect was identified directly, on three communication processes: discursive, lexical-semantic and prosodic processes, and indirectly, on pragmatic process.

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