Showing papers by "Kenneth M. Heilman published in 2007"

Mirror Therapy for Phantom Limb Pain

Abstract: The authors conducted a trial of mirror therapy versus imagery therapy in patients with phantom limb pain after the amputation of a leg or foot. Pain intensity decreased with mirror treatment, as d...

Semantic-phonologic treatment for noun and verb retrieval impairments in aphasia.

Abstract: Nouns and verbs differ in their neural and psycholinguistic attributes. It is not known whether these differences lead to distinct patterns of response to treatment for individuals with word retrieval impairments associated with aphasia. Eight participants with naming disorders induced by left hemisphere strokes were treated with a semantic-phonologic treatment protocol for nouns and verbs using a single participant multiple baseline design. We measured treatment gains in a picture naming measure and other secondary language and communication measures. Treatment led to improved picture naming for trained nouns and verbs in five of eight patients, with no difference evident between nouns and verbs. Improvements for untrained words were minimal. Improvement in verb retrieval was associated with increases on a functional measure of communicative effectiveness. Improvement for nouns and verbs was associated with severity of word retrieval impairment at onset. Although distinct in neural and psycholinguistic attributes, nouns and verbs were affected by treatment in a similar pattern in this group of individuals. Training-specific effects suggest the need for careful selection of training words to have potential for functional benefit in daily communication.

Limb-kinetic apraxia in Parkinson disease

Abstract: To learn if limb-kinetic apraxia (LKA) is associated with Parkinson disease (PD), participants with PD (on medications) and control subjects performed finger tapping (FT), measuring movement speed, and performed coin rotation (CR), measuring precise coordinated but independent finger movements and speed. There were no group differences in FT, a measure of bradykinesia-rigidity, but CR rotation was impaired in PD. Thus, LKA, not related to bradykinesia-rigidity, is associated with PD.

Dissociation of neglect subtypes with transcranial magnetic stimulation

Abstract: Objective: To identify two forms of hemispatial neglect, attentional and intentional, in healthy volunteers using frontal and parietal repetitive transcranial magnetic stimulation (rTMS). Methods: Ten healthy volunteers performed line bisection tasks while viewing stimuli on closed circuit TV. Direct view of the exploring hand and the target was precluded and the TV monitor guided performance. In the normal condition, the direction of hand movement on the table (workspace) was congruent with that on the monitor, and in the reversed condition, the lateral movement in the workspace occurred in the opposite direction on the monitor. The line bisections were performed in three conditions: without rTMS (control), with right frontal rTMS, and with right parietal rTMS. Results: In the normal condition, both right frontal and right parietal rTMS caused a significant rightward deviation (left hemispatial neglect). In the reversed condition, right frontal rTMS continued to cause rightward deviation in the workspace corresponding to leftward bias on the monitor, whereas right parietal rTMS caused leftward deviation in the workspace, corresponding to rightward bias on the monitor. Conclusions: Right frontal repetitive transcranial magnetic stimulation causes motor–intentional neglect, whereas right parietal repetitive transcranial magnetic stimulation causes sensory–attentional neglect. Alternatively, these findings can also be explained based on a dichotomy related to an egocentric-oriented system.

Abnormal emotional word ratings in Parkinson's disease.

Abstract: Blunted facial expressions and diminished expressions of emotional prosody associated with Parkinson's disease (PD) could be attributed to motor rigidity/akinesia. Although impaired recognition of emotional faces and prosody in PD suggests emotional dysfunction is not entirely motor-efferent, comprehension might depend upon imitation with motor feedback. Thus, to learn if patients with PD have an emotional conceptual defect, we examined their ratings for the emotional connotations of words on a 1–9 scale for valence and arousal. When compared to control participants the valence (positive–negative) and arousal (excited–calm) ratings of the PD patients were blunted, but their ratings of the control expense words (expensive–cheap) were not. These blunted emotion ratings suggest that patients with PD have a degradation of their emotional conceptual–semantic system.

Dysfunctional facial emotional expression and comprehension in a patient with corticobasal degeneration.

Abstract: Patients with corticobasal degeneration (CBD) frequently develop orofacial apraxia but little is known about CBD's influence on emotional facial processing. We describe a patient who developed a facial apraxia including an impaired ability to voluntarily generate facial expressions with relative sparing of spontaneous emotional faces. Her ability to interpret the facial expressions of others was also severely impaired. Despite these deficits, the patient had normal affect and normal speech, including expressive and receptive emotional prosody. As patients with corticobasal degeneration are known to manifest both orofacial apraxia and visuospatial dysfunction this patient's expressive and receptive deficits may be independent manifestations of the same underlying disease process. Alternatively, these functions may share a common neuroanatomic substrate that degenerates with CBD.

Artwork before and after onset of progressive nonfluent aphasia.

Abstract: ObjectiveCompare changes in art quality before and after the onset of progressive nonfluent aphasia (PA).BackgroundSome patients with left frontotemporal lobar degeneration (FTLD), particularly PA start painting and improve in art despite their disease. There is only 1 case reported of FTLD where th

Asymmetrical alien hands in corticobasal degeneration.

Abstract: There are several forms of alien limb, but alien limb in corticobasal degeneration (CBD) is not well understood. We studied a patient with CBD who demonstrated two different types of alien limb. With his right hand he demonstrated a tactile avoidance response with levitation. With his left hand, he demonstrated continuous tactile pursuit of the examiner's hand ("tactile mitgehen"). Mitgehen is often associated with frontal dysfunction, but avoidance response and levitation are often associated with parietal dysfunction.

The crossed response inhibition task in Parkinson's disease: disinhibition hyperkinesia.

Abstract: Patients with Parkinson's disease (PD) have dysfunction in frontal-basal ganglia networks. Many of these patients have difficulties with mental processing speed, response inhibition, and shifting between different conceptual sets, suggesting frontal-executive dysfunction. Since frontal lobe dysfunction is associated with disengagement deficits such as perseveration and echopraxia we wanted to learn if patients with PD demonstrated defective response inhibition. Using a brief clinical test called the crossed response inhibition (CRI) task we assessed patients with PD (n = 17), and a group of age matched controls (n = 30). In addition to the CRI, subjects were asked to perform two tests of frontal lobe function: verbal word fluency, anti-saccade test. In the CRI task, patients are instructed to lift the hand opposite to the one the examiner touches. An error is scored whenever the patient makes any movement of the touched (ipsilateral) extremity after stimulation (from shoulder to fingers). The task is performed with the patient's eyes closed. Whereas no differences were found between PD and control subjects on the verbal fluency or anti-saccade tasks, PD patients made significantly more errors on the CRI than did controls. Subsequent analyses found no difference in performance associated with the laterality (asymmetry) of PD symptoms or signs. In addition, there was no difference between PD patients' CRI performance when they were "on" their dopaminergic medications versus when they were "off" these medicines. Based on these findings, it appears that PD is associated with a disengagement-inhibition defect that is not induced by a dopaminergic deficit. In addition, the CRI task might be a brief sensitive bedside task for evaluating frontal dysfunction in PD.

Attentional distractibility by optokinetic stimulation in Alzheimer disease.

Abstract: Objective: Unilateral temporoparietal injury may result in an attentional deficit for stimuli presented in contralesional space. Thus, bilateral temporoparietal degeneration associated with Alzheimer disease (AD) might result in a bilateral attentional disturbance. Tests for hemispatial neglect, however, primarily assess spatial attentional asymmetries, and a bilateral attentional disorder might not be detected with these tests. The goal of this study was to learn whether optokinetic stimulation (OKS) would perturb the balanced attentional deficits of AD patients and alter their spatial allocation of attention. Methods: In Experiment I, 10 AD patients with bilateral temporoparietal glucose hypometabolism on PET and 10 controls bisected lines in two conditions: stationary solid lines superimposed on a moving background and “striped lines” where the whole line was stationary but the stripes within the line moved. The background OKS or the stripes within the line moved leftward or rightward or were stationary. In Experiment II, to investigate whether the influence of background movements would increase with AD severity, we conducted a similar experiment in 56 patients with various stages of AD. Results: In Experiment I, the line bisection errors (LBEs) of AD subjects, but not of the controls, were markedly influenced by both background and within line stripe motions, deviations occurring in the same direction of movement. In Experiment II, LBEs also occurred in the same direction as background movement and increased with dementia severity. Conclusions: These results demonstrate that patients with Alzheimer disease are spatially distracted by moving stimuli.

Reduced verbal learning associated with posterior temporal lobe slow wave activity.

Abstract: Functional imaging has revealed that during verbal-word learning there is activation of the left posterior temporo-parietal region (PTPL). The purpose of this study was to learn if differences in the ability of normal people to learn might be accounted for by differences in electrophysiological (EEG) measures of activation of their left, but not right, PTPL. The Rey Auditory Verbal Learning Test (RAVLT) was administered to 42 men without neurological diseases. Delta magnitude, as measured by quantitative electroencephalography (QEEG), was recorded from the left and right PTPL while the participants sat quietly with their eyes closed. The magnitude of delta EEG activity is inversely proportional to cerebral activation. Based on delta magnitude, comparison groups were created by separating those with low and high delta at the left and right PTPL. Cumulative word learning (CWL) on the RAVLT was computed by subtracting the number of words recalled on the first learning trial from the highest number of words recalled on the fourth or fifth trial and multiplying this difference by the total words recalled during all 5 learning trials. The group with a greater magnitude of left PTPL delta activity had a significantly poorer CWL scores than those with less delta, but the CWL scores of the group with a greater magnitude of delta of the right PTPL was no different that the group with less right-sided delta. No significant differences emerged at any frontal or parietal electrode site. Decreased activation of the left, but not right, PTPL appears to be associated with a decreased verbal leaning ability.

Influence of moving background on line bisection performance in the normal elderly versus patients with hemispatial neglect.

Abstract: Choi KM, Lee BH, Lee SC, Ku BD, Kim E-J, Suh MK, Jeong Y, Heilman KM, Na DL: Influence of moving background on line bisection: performance in the normal elderly versus patients with hemispatial neglect. Am J Phys Med Rehabil 2007; 86:515‐526. Objective: Previous studies have shown that when healthy young participants bisect stationary lines on a moving background (MB) or optokinetic stimulation, they perceive the stationary line moving in the opposite direction of the MB (illusory motion [IM]), and they displace their bisection mark in the direction of the IM. This study attempted to learn whether IM also influences attentional biases of the healthy elderly and patients with hemispatial neglect. Design: In experiment 1, healthy elderly participants and patients with neglect bisected lines in conditions where IM was absent or present. To better understand the MB dichotomy between the healthy elderly and neglect patients, in experiment 2, participants’ eye movements were recorded using an infrared eye tracker. Results: In experiment 1, healthy elderly participants’ biases occurred in the opposite direction of MB when IM was present but in the same direction of MB when IM was absent. In contrast, neglect patients’ biases occurred in the same direction of MB regardless of conditions. Eye movements reflect the spatial direction of attention. In experiment 2, the healthy elderly participants were able to selectively attend to the line, whereas neglect patients were impaired in that they fixated on the line. Conclusions: These results suggest that the healthy elderly can selectively fixate on a line, and with MB, they perceive the stationary line moving, resulting in a bisection bias in the direction of the IM. In contrast, when there is an MB, the patients with neglect are impaired in that they fixate on the line. Thus, they do not perceive IM; instead, they are primarily influenced by the MB.

Lateral and vertical attentional biases in normal individuals.

Abstract: Background: When normal people attempt to bisect lines they often make their mark to the left of midline (pseudoneglect) and when attempting to bisect radial lines normal people tend to bisect distal to the actual midline. These biases might be related to asymmetrical activation induced by making spatial computations or attention-intentional preferences. The purpose of this study was to learn if in the absence of spatial computations normal subjects would demonstrate a left and upward bias. Methods: Normal subjects (139) were given 8 pegs and asked to place these pegs anywhere on a 2-foot-square board. Results: Overall, the subjects displaced the pegs to the left and upward. Conclusions: The overall left-distal bias observed in this experiment was not induced by spatial computation or misperceptions, but is consistent with the postulate that the right hemisphere is dominant for attention-intention and has a relatively distal bias.

Frontal mysteries revealed.

Abstract: In this issue of Neurology , Alexander et al.1 report the results of a study employing an ingenious modification of the Stroop test in 42 subjects with focal lesions at various loci within the frontal lobes, of various etiologies, and 38 normal subjects. Subjects were shown one red or blue letter at a time and instructed to respond only to red X's or blue O's. Distractors included blue X's and red O's, and were admixed with a number of X- and O-like letters (e.g., K, C) in red or blue. They found that predominantly right dorsomedial lesions were associated with disorders of initiation: slowing of all responses as well as complete failure to initiate a response to some targets (errors of omission). They found that left ventrolateral lesions were differentially associated with defective response inhibition: subjects tended to make automatic, reactive responses rather than the volitionally controlled responses needed to meet task instructions (errors of commission)—in essence, a form of utilization behavior.2 This extraordinarily large and well-executed study employing the classic lesion model, though inspired by suggestive findings from functional imaging studies, confirms tentative findings from older lesion studies of smaller numbers of subjects and advances our understanding of the fundamental patterns of organization of function within the frontal lobes. The purpose of the frontal lobes is to develop, select, and execute plans—a spectrum of functions that defines intention. Although there are cytoarchitectonic differences between different regions of the cerebral cortex, the function of individual neural networks is substantially generic, and the role that a particular network plays in brain operations is determined to a major degree by its connectivity with other networks. We can now discern six dimensions of frontal lobe function that reflect the various patterns of connectivity of frontal neural networks (table). Four of these …

Disruption of reciprocal coordination by a medial frontal stroke sparing the corpus callosum.

Abstract: Aleksandr Luria described several tests of higher motor function, including the "reciprocal coordination" test of bimanual coordination. Although these tests are commonly used to assess frontal lobe function, their specific neuroanatomic underpinnings are not completely understood. We describe a man with a medial frontal stroke sparing the corpus callosum with a defect in Luria's reciprocal coordination test but otherwise intact motor abilities, including other tests of higher motor function.

Is decreased dexterity in parkinson disease due to apraxia? Authors' reply

Abstract: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean—neither more nor less.” —Lewis Carroll Quidquid id est, timeo Danaos et dona ferentis. (Whatever it is, I fear Greeks even when they bring gifts [even a word!]) —Virgil Bradykinesia is a cardinal sign of Parkinson disease (PD). Although taken to mean “slow movements,” it is apparent from clinical experience and quantitative studies that the movement impairment in PD is more than simple slowing. Rhythmically repeated movements are progressively damped so that the last movement in a series is often smaller and slower than the first. Movement sequences are more impaired than individual movements. In this issue, Quencer et al. report that patients with PD (on medication) were slower than controls in a coin-rotation task, but not on simple finger tapping.1 They infer from their findings that at least part of the movement disorder …

National Institutes of Health: the lottery.

Abstract: Three recent articles and editorials in Annals of Neurology argued that despite the monetary increase of National Institutes of Health (NIH) funding, neuroscience research has been “stagnant.” The major suggestion offered to improve productivity was to increase collaboration between universities, industry, foundations, and government. Collaboration might enhance productivity, but alterations of NIH funding policies might remedy this stagnation.

Carbidopa/levodopa–responsive myoclonus

Abstract: A 64-year-old right-handed woman's right hand and arm developed spontaneous jerks that eventually involved her trunk. As she had some features of parkinsonism, she was treated with carbidopa/levodopa and her myoclonus dramatically improved. The mechanism accounting for this improvement is unknown.