Showing papers by "Kenneth M. Heilman published in 1999"
TL;DR: Language dominance is more closely associated with the laterality of temporal and spatial movement representations (i.e., ideomotor praxis dominance) than is hand preference.
Abstract: Objective: To determine the relationship of language lateralization and hand preference to praxis performance following left and right hemispheric amobarbital-induced inactivations Background: Patients who are aphasic from left cerebral dysfunction also frequently exhibit ideomotor apraxia in which they make temporal, spatial, and postural errors of learned skilled movements However, hemispheric lateralization of the systems mediating ideomotor praxis in patients with atypical cerebral language dominance (ie, bilateral or right hemispheric language function) remains uncertain Methods: Subjects included 90 patients with intractable seizures who were undergoing the intracarotid amobarbital procedure (IAP) as part of their preoperative evaluation for epilepsy surgery Hand preference was determined by the Benton Handedness Questionnaire Praxis was assessed by the subject’s performance when pantomiming the use of four pictured tools Results: During left IAP, patients with typical language dominance made more ideomotor apraxic errors than did patients with atypical language dominance During right IAP, patients with atypical language dominance made more ideomotor apraxic errors than did patients with typical language dominance Overall, patients with atypical language dominance made fewer ideomotor apraxic errors than did patients with typical language dominance These relationships were present irrespective of hand preference Conclusions: Language dominance is more closely associated with the laterality of temporal and spatial movement representations (ie, ideomotor praxis dominance) than is hand preference Patients with atypical language dominance exhibit more bilateral cerebral distribution of both language and praxis function
228 citations
TL;DR: Preliminary data suggest that left prefrontal rTMS is safe and improves mood in patients with medication-resistant major depression and changes in motor evoked potential threshold suggest that prefrontal rRTMS may alter brain activity at sites remote from the stimulation.
190 citations
TL;DR: An epileptic patient who, during cortical stimulation of her posterior superior temporal gyrus, demonstrated frequent phonemic paraphasias, decreased repetition of words, and yet had intact semantic knowledge, suggest that cortical dysfunction alone may induce conduction aphasia.
186 citations
TL;DR: On the task that appeared to rely most heavily on cognitive flexibility (anagrams), subjects who were most able to solve these problems demonstrated significantly shorter solution times after propranolol than after ephedrine, suggesting that the noradrenergic system exerts a modulatory effect on Cognitive flexibility in problem solving.
Abstract: Stress causes impaired performance on tests of creativity. Drugs that block beta-adrenergic receptors improve test performance in patients with test anxiety. Furthermore, catecholamine precursors (L-DOPA) reduce the flexibility of semantic networks. Our study investigated the effect of noradrenergic system modulation on cognitive flexibility in problem solving. Eighteen normal subjects undertook three problem solving tasks (number series, shape manipulation and anagrams) 45 min after propranolol, placebo and ephedrine. On the task that appeared to rely most heavily on cognitive flexibility (anagrams), subjects who were most able to solve these problems demonstrated significantly shorter solution times (logarithmic scores) after propranolol than after ephedrine. This suggested that the noradrenergic system exerts a modulatory effect on cognitive flexibility in problem solving.
135 citations
TL;DR: The findings suggest that the combination of aberrant approach behaviors associated with frontal lobe injury and an attentional or intentional bias toward the rightsided targets might explain the behavior.
Abstract: Objectives: To study the behavioral and neuroanatomic characteristics of perseverative behavior encountered on a target cancellation task in patients with neglect. Methods: Motor perseverative behavior during line cancellation task was evaluated retrospectively in 60 patients with left hemispatial neglect from right hemispheric stroke. Results: More than 30% of the patients (21 of 60) showed perseveration, manifested as either repetitive cancellation of the same target (18/21) or cancelling extra lines created by the patients themselves (3/21). Neglect severity correlated positively with the frequency of perseverative errors. Perseveration was most prominent in the rightmost portion of the array. Anterior lesions or massive lesions involving anterior and posterior regions were more likely to be associated with motor perseveration than were lesions restricted to posterior areas. Conclusions: Although the mechanism of motor perseveration remains to be elucidated, our findings suggest that the combination of aberrant approach behaviors associated with frontal lobe injury and an attentional or intentional bias toward the rightsided targets might explain the behavior.
107 citations
TL;DR: It is indicated that right sided frontal or subcortical injury may induce contralateral attentional or intentional “approach” behaviours, and may be induced by an attentional bias, an intentional bias, or both.
Abstract: Objective To learn more about the behavioural and anatomical features of ipsilesional neglect. Methods Thirty consecutive patients with spatial neglect were tested on cancellation and line bisection tasks. To learn if patients with ipsilesional neglect demonstrate the sensory-attentional or motor-intentional type of neglect, a video apparatus was used that dissociates these determinants. Results Five patients showed evidence of ipsilesional neglect. This phenomenon was seen only on the line bisection task. All patients with ipsilesional neglect had lesions involving frontal-subcortical regions. Although ipsilesional neglect evolved from early in three of five cases, the other patients displayed ipsilesional neglect without initial contralateral neglect, suggesting that ipsilesional neglect cannot be fully attributed to a compensatory strategy. The results of the tests that used the video apparatus indicate that right sided frontal or subcortical injury may induce contralateral attentional or intentional "approach" behaviours. Conclusions Ipsilesional neglect is most often associated with frontal-subcortical lesions, cannot be entirely attributed to a compensatory strategy, and may be induced by an attentional bias, an intentional bias, or both.
86 citations
TL;DR: Findings lend support to the dopamine hypothesis of developmental stuttering by showing an increase of speech dysfluencies during the levodopa “on” periods.
Abstract: The effects of dopamine on developmental stuttering was studied in a 44 year old man with developmental stuttering and Parkinson's disease during three levodopa "on" periods and three "off" periods. When compared with the "off" periods, during the "on"' periods he demonstrated an increase of speech dysfluencies. These findings lend support to the dopamine hypothesis of developmental stuttering.
69 citations
TL;DR: Clinicians using dopaminergic pharmacotherapy should assess patients for this possible adverse effect of bromocriptine on line bisection in patients with neglect and failure of the action-intention system.
64 citations
TL;DR: The results suggest that the apraxia associated with CBD is initially induced by a production-execution defect with relative sparing of the movement representations.
49 citations
Journal Article•
TL;DR: Patients with Alzheimer disease and with LHD stroke were impaired when producing limb movements after auditory command, and both patient groups were significantly more impaired than the healthy adults.
Abstract: Objective Ideomotor apraxia was studied in patients with Alzheimer disease (AD) and unilateral left hemispheric damaged (LHD) stroke to determine whether these groups differed. Background Given that the neuropathology of AD is bilateral and more diffuse than the localized involvement in patients after an LHD stroke, and given that the cognitive deficits in AD are more widespread than in LHD stroke, the authors predicted that patients with these disorders would differ in response to an auditory command task administered to evaluate ideomotor apraxia, and that the two patient groups would be significantly more impaired than healthy matched control subjects. Methods Twenty-one persons were studied, including equal numbers of patients with AD, patients with unilateral LHD stroke, and control subjects. An auditory command test of limb apraxia was administered and videotaped to score performance and to code spatial-temporal or content errors. Results The patients with AD and LHD stroke were significantly more impaired than healthy control subjects. Whereas the patients with AD and LHD stroke were equally apraxic and did not differ in their performance of transitive limb movements, the patients with AD were significantly more impaired than the patients with stroke when performing intransitive limb movements. A positive correlation was found between severity of dementia and severity of apraxia in the patients with AD. The patients with LHD stroke were as likely to make spatial-temporal as content errors when performing intransitive limb movements, whereas the patients with AD made content errors only. Error types produced with transitive limb movements did not differ between groups; spatial-temporal errors were the most common errors made both by patients with AD and patients with LHD stroke. Conclusions As predicted, patients with AD and with LHD stroke were impaired when producing limb movements after auditory command, and both patient groups were significantly more impaired than the healthy adults. Patients with AD were significantly more impaired than patients with stroke when performing intransitive limb movements, and error types differed by group. Patients with AD and patients with stroke were equally impaired when performing transitive movements, and error types did not differ by group. Patients with ideomotor apraxia are often degraded in their production of transitive and intransitive movements, and the observation that performance may differ depending on the type of limb movement suggests that movement representations for transitive and intransitive movements may be at least partially independent.
48 citations
TL;DR: The impairment seen in the patient with crossed apraxia provides evidence for the fractionation of systems underlying hand preference and skilled movement, andinematic motion analyses of movement linearity, planarity, and the coupling of temporospatial aspects of movements substantiated the parallel impairments in RF and patients with LHApraxia.
Journal Article•
TL;DR: The patient could not perform verbally mediated tests but demonstrated spared ability to match emotional prosody to emotional facial expressions under a variety of conditions, supporting the idea that verbal and emotional communication systems are independent and mediated by different hemispheres.
Abstract: Background: Several studies have demonstrated that patients with right hemisphere damage, when compared with left-hemisphere-damaged controls, are impaired at comprehending emotional prosody. Critics of these studies, however, note that selection may have been biased because left-hemisphere-damaged subjects had good verbal comprehension. Objective: To learn whether a subject with a large left hemisphere stroke and global aphasia could comprehend emotional prosody in spoken material. Method: The authors formally tested speech and language with the Western Aphasia Battery and comprehension of emotional prosody and emotional facial expression with the Florida Affect Battery. Results: The patient could not perform verbally mediated tests but demonstrated spared ability to match emotional prosody to emotional facial expressions under a variety of conditions. Conclusions: These observations further support the idea that verbal and emotional communication systems are independent and mediated by different hemispheres.
TL;DR: The modified Kral procedure is a reliable indicator of facilitory paratonia and a predictor of impaired performance on frontal lobe tests, and both facilitory and oppositionalParatonia strongly predict general cognitive performance.
Abstract: To the Editor:
I was surprised to encounter the word “facilitory” in the title of a recent article by Beversdorf and Heilman.1 Because the word does not exist in the Oxford English Dictionary, second edition, in Webster’s Third New International Dictionary, or in Dorland’s Illustrated Medical Dictionary, 28th edition, I assumed that the “facilitory” in the title was simply a misprint for “facilitatory”—defined by Webster’s as …
TL;DR: The results suggest that ideomotor praxis and motor learning are at least partly dissociable.
TL;DR: Praxis in a patient with CBD is studied and patients who are apraxic from left-parietal strokes are compared to see whether deficits in these other areas may account for the differences in praxic behavior.
TL;DR: A patient with a persistent nonfluent aphasia from a discrete, primarily cortical, frontal-opercular lesion who had impaired syntax but intact repetition and, therefore, did not conform to the traditional classification, is reported on.
TL;DR: Study of a patient with a right frontotemporal stroke who had ipsilesional neglect found a double dissociation: the rightwards motor-intentional cue improved the primary left-sided intentional bias and the leftwards sensory-attentional Cue improved the secondary right-sided attentional bias.
Abstract: Background: Contralesional hemispatial neglect may be induced by an attentional deficit where patients are inattentive to or unaware of stimuli in contralesional hemispace, an intentional deficit where patients are unable to act in or towards contralesional hemispace, or both. The deficits associated with ipsilesional neglect have not been as well chararacterized. Because cueing may be used as a rehabilitative assistive device, we wanted to learn whether the efficacy of an attentional or intentional cue was related to the type of bias. Methods: We studied a patient with a right frontotemporal stroke who had ipsilesional neglect by using a video apparatus that dissociates sensory-attentional and motor-intentional systems. We also performed a cueing experiment with primarily sensory-attentional cues (i.e., read the letter at the end of the line) and primarily motor-intentional cues (i.e., touch the end of the line). Results and Conclusions: Ipsilesional neglect was primarily a motor-intentional deficit with a motor-action bias to the left and a secondary sensory-attentional bias for stimuli to the right. With cueing we found a double dissociation: the rightwards motor-intentional cue improved the primary left-sided intentional bias and the leftwards sensory-attentional cue improved the secondary right-sided attentional bias. Effective rehabilitation strategies need to address both sensory-attentional and motor-intentional deficits in patients with neglect.
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TL;DR: In this article, a detailed analysis of a patient with phonologic alexia suggests that defective knowledge of the position and motion of the articulatory apparatus might contribute to impaired transcoding from letters to sounds.
Abstract: BACKGROUND/OBJECTIVE: Grapheme-to-phoneme conversion (GPC) allows the pronunciation of nonword letter strings and of real words with which the literate reader has no previous experience. Although cross-modal association between visual (orthographic) and auditory (phonemic-input) representations may contribute to GPC, many cases of deep or phonologic alexia result from injury to anterior perisylvian regions. Thus, GPC may rely upon associations between orthographic and articulatory (phonemic-output) representations. METHOD/RESULTS/CONCLUSION: Detailed analysis of a patient with phonologic alexia suggests that defective knowledge of the position and motion of the articulatory apparatus might contribute to impaired transcoding from letters to sounds.
Journal Article•
TL;DR: Emotional experience is not dependent upon activation of and feedback from the autonomic nervous system, and hemispheric asymmetries of emotional experience are partially tested.
Abstract: Objective: To study the relationship between peripheral autonomic arousal and emotional experience. Background: Several theories of emotional experience suggest that this experience is, at least in part, related to feedback from the viscera and the autonomic nervous system. Method: To partially test this hypothesis and to learn if there are hemispheric asymmetries of emotional experience, we studied skin conductance responses (SCR) and verbal report in patients with right hemisphere damage (RHD), patients with left hemisphere damage (LHD), and normal control subjects during the anticipation of electric shocks. Results: During the shock condition, RHD and LHD subjects had smaller SCRs than did normal control subjects. Verbal report measures, however, revealed that subjects reported feeling less pleasant, more aroused, and less in control during the shock condition compared to the no-shock condition. Unlike the SCR results, the verbal report of emotional experience did not differ between the patients with RHD, patients with LHD, and normal control subjects. Conclusions: Emotional experience is not dependent upon activation of and feedback from the autonomic nervous system.
TL;DR: This study provides support for the hemispatial attention-arousal hypotheses of neglect by measuring pupillary response as an index of arousal and does not preclude the possibility that other mechanisms may also be important.
Abstract: OBJECTIVES—Unilateral sensory neglect has been attributed to various defects, including a hemispatial attention-arousal deficit. However, support for this hypothesis has only been indirect. Therefore, the purpose of this study was to further test the hemispatial attentional-arousal hypothesis by measuring pupillary response as an index of arousal.
METHODS—There were two experimental subjects with neglect and six matched controls. Stimuli (Arabic numbers) were presented on the right, left, and centre of a screen. The subjects were asked to look at the number in the centre, on the right, or left of the screen while their pupil diameter was measured.
RESULTS—Unlike the control subjects, the subjects with neglect, who were aware of the left sided stimuli, did not show a pupillary dilatation when they looked at the stimulus on the left.
CONCLUSIONS—Although this study provides support for the hemispatial attention-arousal hypotheses of neglect, it does not preclude the possibility that other mechanisms may also be important.
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