scholarly journals Can Tactile Neglect Occur at an Intra-Limb Level? Vibrotactile Reaction Times in Patients with Right Hemisphere Damage

1994 ◽  
Vol 7 (2) ◽  
pp. 67-77 ◽  
Author(s):  
J. B. Mattingley ◽  
J. L. Bradshaw
Keyword(s):  
Right Hemisphere ◽  
Reaction Times ◽  
The Body ◽  
Right Hemisphere Damage ◽  
Tactile Stimuli ◽  
Supine Posture ◽  
Visual Reaction ◽  
Left And Right ◽  
Tactile Modality ◽  
The Right

Visual reaction time (RT) studies on patients with right hemisphere (RH) damage have demonstrated that the attentional imbalance to stimuli occupying left and right positions exists even within the “intact” ipsilesional hemifield. The purpose of the present study was to test whether such patients might also exhibit relative left-sided impairments in the tactile modality, where stimuli and responses involve the index and middle fingers of the non-hemiplegic ipsilesional hand. Eight patients with RH damage, and eight matched normal controls, were tested using a vibrotactile choice RT paradigm, with the responding hand held in prone or supine posture, and located either at the body midline, or in left or right hemispace. Patients showed significantly slower RTs with the left than the right finger in both hand postures, a difference which remained constant as a function of the hemispatial location of the responding hand. In the prone posture, patients' left finger RTs were slower than those of controls, who showed no difference between left and right finger RTs, while their right finger RTs were faster than those of controls. In the supine posture, both patients and controls exhibited slower left than right finger RTs, though in controls the left finger disadvantage was attributed to biomechanical rather than attentional factors. Patients also made more errors with left than right finger stimuli, both as failures of detection and as incorrect responses, while controls made fewer errors overall and showed no differences between fingers. These data demonstrate a bias in the distribution of attention to tactile stimuli at an intra-limb level, and suggest that the attentional imbalance created by RH damage may be supramodal.

Hemispheric Asymmetries in a Signal Detection Task

1983 ◽  
Vol 57 (3) ◽  
pp. 923-929 ◽  
Author(s):  
John L. Andreassi ◽  
Charles S. Rebert ◽  
Ferol F. Larsen
Keyword(s):  
Signal Detection ◽  
Right Hemisphere ◽  
Reaction Times ◽  
Vigilance Task ◽  
Verbal Stimulus ◽  
Right Visual Field ◽  
Left And Right ◽  
The Right ◽  
Male Subjects ◽  
Central Fixation

Reaction time and signal detection performance were measured during a 78-min. vigilance task. 12 right-handed male subjects served in two experimental sessions. Subjects focused on a central fixation point and responded to signals presented at unpredictable times in one of three locations: 2.5° to right of central fixation, central, and 2.5° to the left of center. Subjects decided whether to press a response key with either the left or right hand with each presentation. Over-all vigilance performance (signal detections and response time) was similar for left and right visual-field presentations. Evidence from reaction times indicated that responses controlled by the left hemisphere were faster to a verbal stimulus (T) while reactions controlled by the right hemisphere were faster to an apparent non-verbal stimulus, an inverted T.

Linguistic Processing and Reaction Time Differences in Stutterers and Nonstutterers

1983 ◽  
Vol 26 (2) ◽  
pp. 181-185 ◽  
Author(s):  
C. Rebekah Hand ◽  
William O. Haynes
Keyword(s):  
Right Hemisphere ◽  
Reaction Times ◽  
Decision Task ◽  
Linguistic Processing ◽  
Hemispheric Processing ◽  
Left And Right ◽  
Response Modes ◽  
Field Efficiency ◽  
The Right ◽  
Visual Hemifields

Linguistic processing by the left and right cerebral hemispheres was investigated in 10 adult male stutterers and l0 matched nonstutterers. Subjects performed a lexical decision task in which nonword and real-word stimuli were presented tachistoscopically to the right and left visual hemifields. Vocal and manual reaction times to real words were measured to assess hemispheric participation in processing linguistic information and to determine differences between response modes. The stuttering group exhibited a left visual field efficiency or right hemisphere preference for this task and were slower in both vocal and manual reaction times. Ramifications for hemispheric processing theories and laryngeal dysfunction hypothesis are discussed.

scholarly journals A transcallosal fiber system between homotopic inferior frontal regions supports complex linguistic processing

2016 ◽  
Author(s):  
Philipp Kellmeyer ◽  
Magnus-Sebastian Vry ◽  
Tonio Ball
Keyword(s):  
Right Hemisphere ◽  
Diffusion Tensor ◽  
The Body ◽  
Canonical Model ◽  
Stroke Recovery ◽  
Linguistic Processing ◽  
Fiber System ◽  
Affective Prosody ◽  
Left And Right ◽  
The Right

AbstractInferior frontal regions in the left and right hemisphere support different aspects of language processing. In the canonical model, left inferior frontal regions are mostly involved in processing based on phonological, syntactic and semantic features of language, whereas the right inferior frontal regions process paralinguistic aspects like affective prosody.Using diffusion tensor imaging (DTI) based probabilistic fiber tracking in 20 healthy volunteers, we identify a callosal fiber system connecting left and right inferior frontal regions that are involved in linguistic processing of varying complexity. Anatomically, we show that the interhemispheric fibers are highly aligned and distributed along a rostral to caudal gradient in the body and genu of the corpus callosum to connect homotopic inferior frontal regions.In light of converging data, taking previous DTI-based tracking studies and clinical case studies into account, our findings suggest that the right inferior frontal cortex not only processes paralinguistic aspects of language (such as affective prosody), as purported by the canonical model, but also supports the computation of linguistic aspects of varying complexity in the human brain. Our model may explain patterns of right hemispheric contribution to stroke recovery as well as disorders of prosodic processing. Beyond language-related brain function, we discuss how interspecies differences in interhemispheric connectivity and fiber density, including the system we described here, may also explain differences in transcallosal information transfer and cognitive abilities across different mammalian species.

Role of Anterior and Posterior Attention Networks in Hemispheric Asymmetries during Lexical Decisions

1991 ◽  
Vol 3 (4) ◽  
pp. 313-321 ◽  
Author(s):  
Atsuko Nakagawa
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Reaction Times ◽  
Attention Networks ◽  
Priming Task ◽  
Left And Right ◽  
The Right ◽  
Prime Target

The role of the left and right hemisphere was examined during semantic priming by antonyms, remote associates, and unrelated words. Targets presented directly to the left hemisphere showed an early facilitation and a late developing inhibition, while targets presented directly to the right hemisphere showed a late developing facilitation of strong and weak associations and little evidence of inhibition. When a visual cue was given prior to each target word, reaction times were facilitated equally in both visual fields and for all prime target relationships. When the priming task was combined with shadowing, reaction times generally increased and all evidence of inhibition in left hemisphere processing disappeared. This supported the idea that the inhibition found in the left hemisphere was due to its interaction with the anterior attention network.

Effects of Left and Right Cerebral Lesions on the Naming Process

1972 ◽  
Vol 35 (3) ◽  
pp. 787-798 ◽  
Author(s):  
Alexis M. Nehemkis ◽  
Peter M. Lewinsohn
Keyword(s):  
Adverse Effect ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Cerebral Hemispheres ◽  
Semantic Interference ◽  
Cerebral Lesions ◽  
Right Hemisphere Damage ◽  
Functional Differences ◽  
Left And Right ◽  
The Right

This experiment tested two major hypotheses: (1) Left hemisphere damage will have a more adverse effect on the naming process than on the ability to read and (2) increments in semantic interference will disrupt the performance of patients with left-hemisphere damage more than that of patients with right-hemisphere damage. Patients with left cerebral lesions consistently performed more poorly than the right-hemisphere-damage patients across all stimulus and response conditions. Aphasic lefts had more difficulty with naming than with reading. Hypothesis 2 was not supported. The findings are discussed with reference to the adequacy of the “verbal-nonverbal” dichotomy for describing functional differences between the left and right cerebral hemispheres.

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.

scholarly journals Sensory deficits in ipsilesional upper-extremity in chronic stroke patients

2015 ◽  
Vol 73 (10) ◽  
pp. 834-839 ◽  
Author(s):  
Núbia Maria Freire Vieira Lima ◽  
Karina Cândido Menegatti ◽  
Érica Yu ◽  
Natália Yumi Sacomoto ◽  
Thais Botossi Scalha ◽  
...  
Keyword(s):  
Right Hemisphere ◽  
Thermal Sensation ◽  
Chronic Stroke ◽  
Sensory Loss ◽  
Stroke Patients ◽  
Sensory Assessment ◽  
Sensory Deficits ◽  
Left Handed ◽  
Right Hemisphere Damage ◽  
The Right

Objective To investigate somatosensory deficits in the ipsilesional wrist and hand in chronic stroke patients and correlate these deficits with contralesional sensorimotor dysfunctions, functional testing, laterality and handedness.Methods Fifty subjects (twenty-two healthy volunteers and twenty-eight stroke patients) underwent evaluation with Semmes-Weinstein monofilaments, the sensory and motor Fugl-Meyer Assessment, the Nottingham Sensory Assessment in both wrists and hands and functional tests.Results Twenty-five patients had sensory changes in the wrist and hand contralateral to the stroke, and eighteen patients (64%) had sensory deficits in the ipsilesional wrist and hand. The most significant ipsilesional sensory loss was observed in the left-handed patients. We found that the patients with brain damage in the right hemisphere had better scores for ipsilesional tactile sensation.Conclusions A reduction in ipsilesional conscious proprioception, tactile or thermal sensation was found in stroke subjects. Right hemisphere damage and right-handed subjects had better scores in ipsilesional tactile sensation.

The right hemisphere: neuropsychological functions

1986 ◽  
Vol 64 (5) ◽  
pp. 693-704 ◽  
Author(s):  
Kenneth M. Heilman ◽  
Dawn Bowers ◽  
Edward Valenstein ◽  
Robert T. Watson
Keyword(s):  
Emotional Disorders ◽  
Right Hemisphere ◽  
Content Type ◽  
Reading And Writing ◽  
The Past ◽  
Right Hemisphere Damage ◽  
Right Hemisphere Dysfunction ◽  
Neuropsychological Functions ◽  
The Right ◽  
Fine Print

✓ In the past two to three decades, clinicians and neuroscientists have been studying the functions of the right hemisphere. Neither hemisphere seems to be dominant in the absolute sense. Each appears to be specialized and is dominant for different functions. However, most functions require the cooperation of both hemispheres. When one is damaged, the other can often compensate for the damaged one. Lesions of the left hemisphere are associated with language (speech, reading, and writing) and praxic disorders, and lesions of the right hemisphere can result in visuospatial, attentional, and emotional disorders. The authors review some of the major behavioral disorders associated with right hemisphere dysfunction and concentrate on three major types of disorders — visuospatial, attentional, and emotional. Although not all the behavioral defects associated with right hemisphere damage can be subgrouped under these three types, they are the ones most often associated with right hemisphere lesions.

Bihemispheric Language: How the Two Hemispheres Collaborate in the Processing of Language

2004 ◽  
Author(s):  
Norman D. Cook
Keyword(s):  
Language Processing ◽  
Right Hemisphere ◽  
Central Question ◽  
Linguistic Processing ◽  
Figures Of Speech ◽  
Language Functions ◽  
Left And Right ◽  
Level Of Understanding ◽  
The Right

Speech production in most people is strongly lateralized to the left hemisphere (LH), but language understanding is generally a bilateral activity. At every level of linguistic processing that has been investigated experimentally, the right hemisphere (RH) has been found to make characteristic contributions, from the processing of the affective aspects of intonation, through the appreciation of word connotations, the decoding of the meaning of metaphors and figures of speech, to the understanding of the overall coherency of verbal humour, paragraphs and short stories. If both hemispheres are indeed engaged in linguistic decoding and both processes are required to achieve a normal level of understanding, a central question concerns how the separate language functions on the left and right are integrated. This chapter reviews relevant studies on the hemispheric contributions to language processing and the role of interhemispheric communications in cognition.

Right hemisphere speech perception revealed by amobarbital injection and electrical interference

Neurology ◽  
1998 ◽  
Vol 51 (2) ◽  
pp. 458-464 ◽  
Author(s):  
D. Boatman ◽  
J. Hart ◽  
R. P. Lesser ◽  
N. Honeycutt ◽  
N. B. Anderson ◽  
...  
Keyword(s):  
Speech Perception ◽  
Left Hemisphere ◽  
Temporal Lobe ◽  
Right Hemisphere ◽  
Adult Brain ◽  
Left Posterior ◽  
Left And Right ◽  
Sodium Amobarbital ◽  
The Right ◽  
Electrical Interference

Objective: To investigate the right hemispheric speech perception capabilities of an adult right-handed patient with seizures.Methods: Consecutive, unilateral, intracarotid sodium amobarbital injections and left hemispheric electrical interference mapping were used to determine lateralization and localization of speech perception, measured as syllable discrimination.Results: Syllable discrimination remained intact after left and right intracarotid sodium amobarbital injections. Language otherwise strongly lateralized to the left hemisphere. Despite evidence of bilateral speech perception capabilities, electrical interference testing in the left posterior temporal lobe impaired syllable discrimination.Conclusions: The results suggest a functionally symmetric, parallel system in the adult brain with preferential use of left hemispheric pathways for speech perception.

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