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Georg Goldenberg - One of the best experts on this subject based on the ideXlab platform.
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a network underlying human higher order motor control insights from machine learning based lesion behaviour mapping in apraxia of Pantomime
Cortex, 2019Co-Authors: Christoph Sperber, Daniel Wiesen, Georg Goldenberg, Hansotto KarnathAbstract:Neurological patients with apraxia of Pantomime provide us with a unique opportunity to study the neural correlates of higher-order motor function. Previous studies using lesion-behaviour mapping methods led to inconsistent anatomical results, reporting various lesion locations to induce this symptom. We hypothesised that the inconsistencies might arise from limitations of mass-univariate lesion-behaviour mapping approaches if our ability to Pantomime the use of objects is organised in a brain network. Thus, we investigated apraxia of Pantomime by using multivariate lesion behaviour mapping based both on support vector regression and sparse canonical correlations in a sample of 130 left-hemisphere stroke patients. Both multivariate methods identified multiple areas to underlie high-order motor control, including inferior parietal lobule, precentral gyrus, posterior parts of middle temporal cortex, and insula. Further, long association fibres were affected, such as the superior longitudinal fascicle, inferior occipito-frontal fascicle, uncinated fascicle, and superior occipito-frontal fascicle. The findings underline the benefits of multivariate lesion-behaviour mapping in brain networks and provide new insights into the brain networks underlying higher-order motor control.
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the network underlying human higher order motor control insights from machine learning based lesion behaviour mapping in apraxia
bioRxiv, 2019Co-Authors: Christoph Sperber, Daniel Wiesen, Georg Goldenberg, Hansotto KarnathAbstract:Neurological patients with apraxia of Pantomime provide us with a unique opportunity to study the neural correlates of higher-order motor function. Previous studies using lesion-behaviour mapping methods led to inconsistent anatomical results, reporting various lesion locations to induce this symptom. We hypothesised that the inconsistencies might arise from limitations of mass-univariate lesion-behaviour mapping approaches if our ability to Pantomime the use of objects is organised in a brain network. Thus, we investigated apraxia of Pantomime by using multivariate lesion behaviour mapping based both on support vector regression and sparse canonical correlations in a sample of 130 left-hemisphere stroke patients. Both multivariate methods identified multiple areas to underlie high-order motor control, including inferior parietal lobule, precentral gyrus, posterior parts of middle temporal cortex, and insula. Further, long association fibres were affected, such as the superior longitudinal fascicle, inferior occipito-frontal fascicle, uncinated fascicle, and superior occipito-frontal fascicle. The findings thus not only underline the benefits of multivariate lesion-behaviour mapping in brain networks, but they also uncovered that higher-order motor control indeed is based on a common anatomical network.
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shared neural substrates of apraxia and aphasia
Neuropsychologia, 2015Co-Authors: Georg Goldenberg, Jennifer RanderathAbstract:Apraxia is regularly associated with aphasia, but there is controversy whether their co-occurrence is the expression of a common basic deficit or results from anatomical proximity of their neural substrates. However, neither aphasia nor apraxia is an indivisible entity. Both diagnoses embrace diverse manifestations that may occur more or less independently from each other. Thus, the question whether apraxia is always accompanied by aphasia may lead to conflicting answers depending on which of their manifestations are considered. We used voxel based lesion symptom mapping (VLSM) for exploring communalities between lesion sites associated with aphasia and with apraxia. Linguistic impairment was assessed by the Aachen Aphasia Test (AAT) subtests naming, comprehension, repetition, written language, and Token Test. Apraxia was examined for imitation of meaningless hand and finger postures and for Pantomime of tool use. There were two areas of overlap between aphasia and apraxia. Lesions in the anterior temporal lobe interfered with Pantomime of tool use and with all linguistic tests. In the left inferior parietal lobe there was a large area where lesions were associated with defective imitation of hand postures and with poor scores on written language and the Token Test. Within this large area there were also two spots in supramarginal and angular gyrus where lesions were also associated with defective Pantomime. We speculate that the coincidence of language impairment and defective Pantomime after anterior temporal lesions is due to impaired access to semantic memory. The combination of defective imitation of hand postures with poor scores on Token Test and written language is not easily compatible with a crucial role of parietal regions for the conversion of concepts of intended actions into motor commands. It accords better with a role of left inferior parietal lobe regions for the categorical perception of spatial relationships.
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tool use and mechanical problem solving in apraxia
Neuropsychologia, 1998Co-Authors: Georg Goldenberg, Sonja HagmannAbstract:Moorlaas (1928) proposed that apraxic patients can identify objects and can remember the purpose they have been made for but do not know the way in which they must be used to achieve that purpose. Knowledge about the use of objects and tools can have two sources: It can be based on retrieval of instructions of use from semantic memory or on a direct inference of function from structure. The ability to infer function from structure enables subjects to use unfamiliar tools and to detect alternative uses of familiar tools. It is the basis of mechanical problem solving. The purpose of the present study was to analyze retrieval of instruction of use, mechanical problem solving, and actual tool use in patients with apraxia due to circumscribed lesions of the left hemisphere. For assessing mechanical problem solving we developed a test of selection and application of novel tools. Access to instruction of use was tested by Pantomime of tool use. Actual tool use was examined for the same familiar tools. Forty two patients with left brain damage (LBD) and aphasia, 22 patients with right brain damage (RBD) and 22 controls were examined. Only LBD patients differed from controls on all tests. RBD patients had difficulties with the use but not with the selection of novel tools. In LBD patients there was a significant correlation between Pantomime of tool use and novel tool selection but there were single cases who scored in the defective range on one of these tests and normally on the other. Analysis of LBD patients' lesions suggested that frontal lobe damage does not disturb novel tool selection. Only LBD patients who failed on Pantomime of object use and on novel tool selection committed errors in actual use of familiar tools. The finding that mechanical problem solving is invariably defective in apraxic patients who commit errors with familiar tools is in good accord with clinical observations, as the gravity of their errors goes beyond what one would expect as a mere sequel of loss of access to instruction of use.
Hansotto Karnath - One of the best experts on this subject based on the ideXlab platform.
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a network underlying human higher order motor control insights from machine learning based lesion behaviour mapping in apraxia of Pantomime
Cortex, 2019Co-Authors: Christoph Sperber, Daniel Wiesen, Georg Goldenberg, Hansotto KarnathAbstract:Neurological patients with apraxia of Pantomime provide us with a unique opportunity to study the neural correlates of higher-order motor function. Previous studies using lesion-behaviour mapping methods led to inconsistent anatomical results, reporting various lesion locations to induce this symptom. We hypothesised that the inconsistencies might arise from limitations of mass-univariate lesion-behaviour mapping approaches if our ability to Pantomime the use of objects is organised in a brain network. Thus, we investigated apraxia of Pantomime by using multivariate lesion behaviour mapping based both on support vector regression and sparse canonical correlations in a sample of 130 left-hemisphere stroke patients. Both multivariate methods identified multiple areas to underlie high-order motor control, including inferior parietal lobule, precentral gyrus, posterior parts of middle temporal cortex, and insula. Further, long association fibres were affected, such as the superior longitudinal fascicle, inferior occipito-frontal fascicle, uncinated fascicle, and superior occipito-frontal fascicle. The findings underline the benefits of multivariate lesion-behaviour mapping in brain networks and provide new insights into the brain networks underlying higher-order motor control.
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the network underlying human higher order motor control insights from machine learning based lesion behaviour mapping in apraxia
bioRxiv, 2019Co-Authors: Christoph Sperber, Daniel Wiesen, Georg Goldenberg, Hansotto KarnathAbstract:Neurological patients with apraxia of Pantomime provide us with a unique opportunity to study the neural correlates of higher-order motor function. Previous studies using lesion-behaviour mapping methods led to inconsistent anatomical results, reporting various lesion locations to induce this symptom. We hypothesised that the inconsistencies might arise from limitations of mass-univariate lesion-behaviour mapping approaches if our ability to Pantomime the use of objects is organised in a brain network. Thus, we investigated apraxia of Pantomime by using multivariate lesion behaviour mapping based both on support vector regression and sparse canonical correlations in a sample of 130 left-hemisphere stroke patients. Both multivariate methods identified multiple areas to underlie high-order motor control, including inferior parietal lobule, precentral gyrus, posterior parts of middle temporal cortex, and insula. Further, long association fibres were affected, such as the superior longitudinal fascicle, inferior occipito-frontal fascicle, uncinated fascicle, and superior occipito-frontal fascicle. The findings thus not only underline the benefits of multivariate lesion-behaviour mapping in brain networks, but they also uncovered that higher-order motor control indeed is based on a common anatomical network.
Melvyn A Goodale - One of the best experts on this subject based on the ideXlab platform.
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real time vision tactile cues and visual form agnosia removing haptic feedback from a natural grasping task induces Pantomime like grasps
Frontiers in Human Neuroscience, 2015Co-Authors: Robert L Whitwell, Tzvi Ganel, Caitlin M Byrne, Melvyn A GoodaleAbstract:Investigators study the kinematics of grasping movements (prehension) under a variety of conditions to probe visuomotor function in normal and brain-damaged individuals. When patient DF, who suffers from visual form agnosia, performs natural grasps, her in-flight hand aperture is scaled to the widths of targets ('grip scaling') that she cannot discriminate amongst. In contrast, when DF's Pantomime grasps are based on a memory of a previewed object, her grip scaling is very poor. Her failure on this task has been interpreted as additional support for the dissociation between the use of object vision for action and object vision for perception. Curiously, however, when DF directs her Pantomimed grasps towards a displaced imagined copy of a visible object where her fingers make contact with the surface of the table, her grip scaling does not appear to be particularly poor. In the first of two experiments, we revisit this previous work and show that her grip scaling in this real-time Pantomime grasping task does not differ from controls, suggesting that terminal tactile feedback from a proxy of the target can maintain DF's grip scaling. In a second experiment with healthy participants, we tested a recent variant of a grasping task in which no tactile feedback is available (i.e. no haptic feedback) by comparing the kinematics of target-directed grasps with and without haptic feedback to those of real-time Pantomime grasps without haptic feedback. Compared to natural grasps, removing haptic feedback increased RT, slowed the velocity of the reach, reduced grip aperture, sharpened the slopes relating grip aperture to target width, and reduced the final grip aperture. All of these effects were also observed in the Pantomime grasping task. Taken together, these results provide compelling support for the view that removing haptic feedback induces a switch from real-time visual control to one that depends more on visual perception and cognitive supervision.
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Real-time vision, tactile cues, and visual form agnosia in Pantomimed grasping: removing haptic feedback induces a switch from natural to Pantomime-like grasps
Frontiers Media S.A., 2015Co-Authors: Robert L Whitwell, Tzvika Eganel, Caitlin Ebyrne, Melvyn A GoodaleAbstract:Investigators study the kinematics of grasping movements (prehension) under a variety of conditions to probe visuomotor function in normal and brain-damaged individuals. When patient DF, who suffers from visual form agnosia, performs natural grasps, her in-flight hand aperture is scaled to the widths of targets ('grip scaling') that she cannot discriminate amongst. In contrast, when DF's Pantomime grasps are based on a memory of a previewed object, her grip scaling is very poor. Her failure on this task has been interpreted as additional support for the dissociation between the use of object vision for action and object vision for perception. Curiously, however, when DF directs her Pantomimed grasps towards a displaced imagined copy of a visible object where her fingers make contact with the surface of the table, her grip scaling does not appear to be particularly poor. In the first of two experiments, we revisit this previous work and show that her grip scaling in this real-time Pantomime grasping task does not differ from controls, suggesting that terminal tactile feedback from a proxy of the target can maintain DF's grip scaling. In a second experiment with healthy participants, we tested a recent variant of a grasping task in which no tactile feedback is available (i.e. no haptic feedback) by comparing the kinematics of target-directed grasps with and without haptic feedback to those of real-time Pantomime grasps without haptic feedback. Compared to natural grasps, removing haptic feedback increased RT, slowed the velocity of the reach, reduced grip aperture, sharpened the slopes relating grip aperture to target width, and reduced the final grip aperture. All of these effects were also observed in the Pantomime grasping task. Taken together, these results provide compelling support for the view that removing haptic feedback induces a switch from real-time visual control to one that depends more on visual perception and cognitive supervision
Christoph Sperber - One of the best experts on this subject based on the ideXlab platform.
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a network underlying human higher order motor control insights from machine learning based lesion behaviour mapping in apraxia of Pantomime
Cortex, 2019Co-Authors: Christoph Sperber, Daniel Wiesen, Georg Goldenberg, Hansotto KarnathAbstract:Neurological patients with apraxia of Pantomime provide us with a unique opportunity to study the neural correlates of higher-order motor function. Previous studies using lesion-behaviour mapping methods led to inconsistent anatomical results, reporting various lesion locations to induce this symptom. We hypothesised that the inconsistencies might arise from limitations of mass-univariate lesion-behaviour mapping approaches if our ability to Pantomime the use of objects is organised in a brain network. Thus, we investigated apraxia of Pantomime by using multivariate lesion behaviour mapping based both on support vector regression and sparse canonical correlations in a sample of 130 left-hemisphere stroke patients. Both multivariate methods identified multiple areas to underlie high-order motor control, including inferior parietal lobule, precentral gyrus, posterior parts of middle temporal cortex, and insula. Further, long association fibres were affected, such as the superior longitudinal fascicle, inferior occipito-frontal fascicle, uncinated fascicle, and superior occipito-frontal fascicle. The findings underline the benefits of multivariate lesion-behaviour mapping in brain networks and provide new insights into the brain networks underlying higher-order motor control.
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the network underlying human higher order motor control insights from machine learning based lesion behaviour mapping in apraxia
bioRxiv, 2019Co-Authors: Christoph Sperber, Daniel Wiesen, Georg Goldenberg, Hansotto KarnathAbstract:Neurological patients with apraxia of Pantomime provide us with a unique opportunity to study the neural correlates of higher-order motor function. Previous studies using lesion-behaviour mapping methods led to inconsistent anatomical results, reporting various lesion locations to induce this symptom. We hypothesised that the inconsistencies might arise from limitations of mass-univariate lesion-behaviour mapping approaches if our ability to Pantomime the use of objects is organised in a brain network. Thus, we investigated apraxia of Pantomime by using multivariate lesion behaviour mapping based both on support vector regression and sparse canonical correlations in a sample of 130 left-hemisphere stroke patients. Both multivariate methods identified multiple areas to underlie high-order motor control, including inferior parietal lobule, precentral gyrus, posterior parts of middle temporal cortex, and insula. Further, long association fibres were affected, such as the superior longitudinal fascicle, inferior occipito-frontal fascicle, uncinated fascicle, and superior occipito-frontal fascicle. The findings thus not only underline the benefits of multivariate lesion-behaviour mapping in brain networks, but they also uncovered that higher-order motor control indeed is based on a common anatomical network.
Robert L Whitwell - One of the best experts on this subject based on the ideXlab platform.
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real time vision tactile cues and visual form agnosia removing haptic feedback from a natural grasping task induces Pantomime like grasps
Frontiers in Human Neuroscience, 2015Co-Authors: Robert L Whitwell, Tzvi Ganel, Caitlin M Byrne, Melvyn A GoodaleAbstract:Investigators study the kinematics of grasping movements (prehension) under a variety of conditions to probe visuomotor function in normal and brain-damaged individuals. When patient DF, who suffers from visual form agnosia, performs natural grasps, her in-flight hand aperture is scaled to the widths of targets ('grip scaling') that she cannot discriminate amongst. In contrast, when DF's Pantomime grasps are based on a memory of a previewed object, her grip scaling is very poor. Her failure on this task has been interpreted as additional support for the dissociation between the use of object vision for action and object vision for perception. Curiously, however, when DF directs her Pantomimed grasps towards a displaced imagined copy of a visible object where her fingers make contact with the surface of the table, her grip scaling does not appear to be particularly poor. In the first of two experiments, we revisit this previous work and show that her grip scaling in this real-time Pantomime grasping task does not differ from controls, suggesting that terminal tactile feedback from a proxy of the target can maintain DF's grip scaling. In a second experiment with healthy participants, we tested a recent variant of a grasping task in which no tactile feedback is available (i.e. no haptic feedback) by comparing the kinematics of target-directed grasps with and without haptic feedback to those of real-time Pantomime grasps without haptic feedback. Compared to natural grasps, removing haptic feedback increased RT, slowed the velocity of the reach, reduced grip aperture, sharpened the slopes relating grip aperture to target width, and reduced the final grip aperture. All of these effects were also observed in the Pantomime grasping task. Taken together, these results provide compelling support for the view that removing haptic feedback induces a switch from real-time visual control to one that depends more on visual perception and cognitive supervision.
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Real-time vision, tactile cues, and visual form agnosia in Pantomimed grasping: removing haptic feedback induces a switch from natural to Pantomime-like grasps
Frontiers Media S.A., 2015Co-Authors: Robert L Whitwell, Tzvika Eganel, Caitlin Ebyrne, Melvyn A GoodaleAbstract:Investigators study the kinematics of grasping movements (prehension) under a variety of conditions to probe visuomotor function in normal and brain-damaged individuals. When patient DF, who suffers from visual form agnosia, performs natural grasps, her in-flight hand aperture is scaled to the widths of targets ('grip scaling') that she cannot discriminate amongst. In contrast, when DF's Pantomime grasps are based on a memory of a previewed object, her grip scaling is very poor. Her failure on this task has been interpreted as additional support for the dissociation between the use of object vision for action and object vision for perception. Curiously, however, when DF directs her Pantomimed grasps towards a displaced imagined copy of a visible object where her fingers make contact with the surface of the table, her grip scaling does not appear to be particularly poor. In the first of two experiments, we revisit this previous work and show that her grip scaling in this real-time Pantomime grasping task does not differ from controls, suggesting that terminal tactile feedback from a proxy of the target can maintain DF's grip scaling. In a second experiment with healthy participants, we tested a recent variant of a grasping task in which no tactile feedback is available (i.e. no haptic feedback) by comparing the kinematics of target-directed grasps with and without haptic feedback to those of real-time Pantomime grasps without haptic feedback. Compared to natural grasps, removing haptic feedback increased RT, slowed the velocity of the reach, reduced grip aperture, sharpened the slopes relating grip aperture to target width, and reduced the final grip aperture. All of these effects were also observed in the Pantomime grasping task. Taken together, these results provide compelling support for the view that removing haptic feedback induces a switch from real-time visual control to one that depends more on visual perception and cognitive supervision
