scholarly journals Impaired anticipatory control of fingertip forces in patients with a pure motor or sensorimotor lacunar syndrome

Brain ◽  
2006 ◽  
Vol 129 (6) ◽  
pp. 1415-1425 ◽  
Author(s):  
P. Raghavan
Keyword(s):  
Anticipatory Control ◽  
Lacunar Syndrome ◽  
Fingertip Forces ◽  
Pure Motor

Specificity of Internal Representations Underlying Grasping

2000 ◽  
Vol 84 (5) ◽  
pp. 2390-2397 ◽  
Author(s):  
Iran Salimi ◽  
Ian Hollender ◽  
Wendy Frazier ◽  
Andrew M. Gordon
Keyword(s):  
Explicit Knowledge ◽  
Precision Grip ◽  
Internal Representation ◽  
Vertical Axis ◽  
The Body ◽  
Load Force ◽  
Anticipatory Control ◽  
Internal Representations ◽  
Lift Off ◽  
Fingertip Forces

The present study examines anticipatory control of fingertip forces during grasping based on the center of mass (CM) of a manipulated object. Subjects lifted an object using a precision grip while the fingertip forces and the angle about the vertical axis (roll) were measured. The object's CM could be shifted to the left or right of the object's center parallel to the grip axis without changing it's visual appearance. Subjects performed 20 lifts with the CM in the center, left, and right side of the object, respectively. Subjects were instructed to lift the object while preventing it from tilting. Within three to five lifts, subjects were able to asymmetrically partition the load force development before lift-off such that it was higher in the digit opposing the CM. This anticipatory load force partitioning prevented the object from rolling sideways at lift-off. To determine whether the internal representation underlying the anticipatory control is specific to the effectors used to form it, subjects performed five lifts with the right hand with the CM on one side. Following these lifts, they rotated the object 180° around the vertical axis and performed one lift with the same hand or they translated the object to the left side of the body (with or without rotating it) and performed one lift with the left hand. Despite subjects' explicit knowledge of the new weight distribution, they were unable to appropriately scale the load forces at each digit, resulting in a subsequent large roll of the object. The findings suggest that within a few lifts subjects achieve a stable internal representation which accounts for the object's CM and is used to scale the fingertip forces in advance. They also suggest that this representation, which is used for anticipatory control of fingertip forces, is specific to the effectors used to form it. We propose that multiple internal representations may be used during the anticipatory control of grasping.

scholarly journals Basilar Artery Stenosis Mimicking the Lacunar Syndrome of Pure Motor Hemiparesis

2003 ◽  
Vol 30 (2) ◽  
pp. 159-162 ◽  
Author(s):  
David K. Chan ◽  
Frank L. Silver
Keyword(s):  
Basilar Artery ◽  
Small Vessel Disease ◽  
Internal Capsule ◽  
Artery Stenosis ◽  
Large Artery ◽  
Lacunar Syndrome ◽  
Basilar Artery Stenosis ◽  
The Right ◽  
Angioplasty And Stenting ◽  
Pure Motor

ABSTRACT:Background:Stereotyped, repeated transient ischemic attacks manifesting as pure motor hemiparesis are most often attributed to ischemia of the internal capsule or ventral pons resulting from in situ disease of the small penetrating arteries.Case description:We report a 61-year-old man presenting with recurrent episodes of left-sided weakness consistent with the lacunar syndrome of pure motor hemiparesis. Subsequent neuroimaging revealed infarction of the right ventral pons and a critical basilar artery stenosis as the inciting lesion. Despite maximal antithrombotic therapy, he continued to have repeated symptoms. Angioplasty and stenting were attempted but both failed due to plaque recoil and technical difficulties. After the procedure, the patient had no further ischemic episodes and remained symptom-free at two months.Conclusions:This case illustrates the imprecise and discordant relationship between the mode of presentation of a stroke syndrome and its presumed pathophysiology. The lacunar syndrome of pure motor hemiparesis should be recognized by clinicians as a mode of stroke presentation due not only to small vessel disease, but also to large artery atherosclerotic disease such as basilar artery stenosis. Prompt institution of treatment can lead to a good clinical outcome.

scholarly journals Pure Motor Stroke Secondary to Cerebral Infarction of Recurrent Artery of Heubner after Mild Head Trauma: A Case Report

2016 ◽  
Vol 4 (1) ◽  
pp. 139-141
Author(s):  
Ali Yilmaz ◽  
Zahir Kizilay ◽  
Ayca Ozkul ◽  
Bayram Çirak
Keyword(s):  
Ischemic Stroke ◽  
Head Trauma ◽  
Distal Part ◽  
Brain Mri ◽  
Artery Occlusion ◽  
Acute Ischemia ◽  
Post Traumatic ◽  
The Brain ◽  
Perforating Arteries ◽  
Pure Motor

BACKGROUND: The recurrent Heubner's artery is the distal part of the medial striate artery. Occlusion of the recurrent artery of Heubner, classically contralateral hemiparesis with fasciobrachiocrural predominance, is attributed to the occlusion of the recurrent artery of Heubner and is widely known as a stroke syndrome in adults. However, isolated occlusion of the deep perforating arteries following mild head trauma also occurs extremely rarely in childhood.CASE REPORT: Here we report the case of an 11-year-old boy with pure motor stroke. The brain MRI showed an acute ischemia in the recurrent artery of Heubner supply area following mild head trauma. His fasciobrachial hemiparesis and dysarthria were thought to be secondary to the stretching of deep perforating arteries leading to occlusion of the recurrent artery of Heubner.CONCLUSION: Post-traumatic pure motor ischemic stroke can be secondary to stretching of the deep perforating arteries especially in childhood.

Effect of surface textures on the fingertip forces perception and output

2021 ◽  
Author(s):  
Kenta Kishishita ◽  
Naoki Sakamoto ◽  
Hiroaki Muranami ◽  
Kazuhiro Hattori ◽  
Yuichi Kurita
Keyword(s):  
Surface Textures ◽  
Fingertip Forces ◽  
Effect Of Surface
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