Hand Preferences and Hand Ability in Congenitally Blind Children

1993 ◽  
Vol 46 (1) ◽  
pp. 35-50 ◽  
Author(s):  
Miriam Ittyerah

Congenitally blind and sighted blindfolded children between the ages of 6 and 14 years were tested for hand preference with performance tasks. There were no differences between the groups in direction or degree of hand preference. The degree of handedness increased with age and was essentially linear though the blind seemed to be somewhat less lateralized at the younger ages. When the same groups were required to match three-dimensional bricks for height, depth, breadth, and volume, no hand advantages were found for either group. Both groups of children improved in their accuracy of spatial discriminations with age. Further, the degree of lateralization on the handedness task did not relate to ability on the tactile task or to differences between the right and left hands on the tactile task. Thus, there is no effect of blindness on tactile matching ability nor is there an effect of the hand used in the task.

1988 ◽  
Vol 66 (2) ◽  
pp. 403-406 ◽  
Author(s):  
Lester Hunt ◽  
Heidi Edwards ◽  
Kathryn Quest

The present study investigated the effects of the use of the right and left hands on haptic identification of letters of the alphabet. Each of the 64 right-handed subjects was given three series of randomly ordered presentations of the 26 letters of the alphabet. The subjects were asked to feel each letter and name correctly each letter as quickly but as accurately as possible. Analysis showed faster identification by those subjects using their left hands on Series 1 with no hand-differences appearing on Series 2 and 3. Significant over-all improvement in identification time occured with practice. The results were interpreted in terms of a novelty hypothesis of right-hemisphere function and an explanation of perceptual learning of letter identification.


Author(s):  
Kermit G. Davis ◽  
William S. Marras ◽  
Kevin P. Granata

This study documented three-dimensional spine loading associated with asymmetric lifting while using either one or two hands to perform the task. Lift asymmetry was defined as a function of the load origin relative to the sagittal plane of the body. Lifts occurred at 0, 30, or 60 degrees off the sagittal plane on both sides of the body (lifting from the right and from the left relative to the sagittal plane). Ten subjects lifted a 13.7 kg box from one of these origins to a sagittally symmetric destination. Spinal loads were estimated through the use of a validated EMG-assisted model. Spine compression and lateral shear forces increased as the lift origin became more asymmetric. However, spine compression and lateral shear increased by about twice the rate when lifting from origins to the left of the sagittal plane compared to lifting from origins to the right of the sagittal plane. Anterior-posterior spinal shear decreased as asymmetry increased with larger decreases occurring when lift origins occurred to the right of the sagittal plane. One-hand lifting changed the compression and shear profiles significantly. One-hand lifts using the hand on the same side of the body as the load resulted in compression forces that were approximately equal to those observed when lifting with two hands in a sagittally symmetric position. Anterior -posterior shear decreased and lateral shear increased under these conditions. These results reflect the trade-offs that must be considered among spinal forces during asymmetric lifting while using one or two hands.


Author(s):  
Maruti Ram Gudavalli

This study presents the dynamic load characteristics of chiropractors delivering posterior to anterior double thenar thoracic spinal manipulations to a mannequin. A total of 36 thrusts were delivered by the three chiropractors to a mannequin that has similar shape and texture of a human. Two three-dimensional force transducers were used between the doctor’s hand and the mannequin. Parameters of the duration, rate of loading, preload and peak loads were extracted from the data for the three chiropractors. Average peak loads in the normal direction reached 247 N and 217N in the right and left hands. The shear forces reached 36 and 18N in the right and left hand. The rates of loading have reached 804N/s and 761N/s in the right and left hands. Average durations of thrust were 242msecs. The three doctors had distinct characteristics in pre loads, durations of loading and rates of loading.


1994 ◽  
Vol 78 (1) ◽  
pp. 287-290 ◽  
Author(s):  
Uner Tan

Grasp-reflex strengths were quantitatively measured from the right and left hands of 70 full-term human neonates. The right-left grasp-reflex linearly correlated with grasp-reflex only of the right hand in neonates with a right-ear-facing-out prenatal position. In neonates with left-ear-facing-out prenatal position, this grasp-reflex linearly increased with the grasp-reflex of the right hand and linearly decreased with the grasp reflex of the left hand. It was suggested that grasp-reflex asymmetry in neonates may, at least partly, depend upon prenatal position, which may also influence the later developing hand preference in humans.


2017 ◽  
pp. 1
Author(s):  
عالية بدر عبدالله ◽  
ضيف الله زامل حربي

Author(s):  
Emanuela Gualdi-Russo ◽  
Natascia Rinaldo ◽  
Alba Pasini ◽  
Luciana Zaccagni

The aims of this study were to develop and validate an instrument to quantitatively assess the handedness of basketballers in basketball tasks (Basketball Handedness Inventory, BaHI) and to compare it with their handedness in daily activities by the Edinburgh Handedness Inventory (EHI). The participants were 111 basketballers and 40 controls. All subjects completed the EHI and only basketballers filled in the BaHI. To validate the BaHI, a voluntary subsample of basketballers repeated the BaHI. Exploratory and confirmatory factor analyses supported a two-factor model. Our results show that: (i) Handedness score (R) in daily actions did not differ between basketball players (R by EHI = 69.3 ± 44.6) and the control group (R by EHI = 64.5 ± 58.6); (ii) basketballers more frequently favored performing certain sport tasks with the left hand or mixed hands (as highlighted by R by BaHI = 50.1 ± 47.1), although their choice was primarily the right hand in everyday gestures; and (iii) this preference was especially true for athletes at the highest levels of performance (R by BaHI of A1 league = 38.6 ± 58.3) and for those playing in selected roles (point guard’s R = 29.4 ± 67.4). Our findings suggest that professional training induces handedness changes in basketball tasks. The BaHI provides a valid and reliable measure of the skilled hand in basketball. This will allow coaches to assess mastery of the ball according to the hand used by the athlete in the different tasks and roles.


1998 ◽  
Vol 1 (1) ◽  
pp. 13-22
Author(s):  
Helmut Strasser ◽  
Baoquiu Wang

The focus of this research was to investigate how maximum torque and muscle forces were affected by pronation and supination, i.e., inward and outward rotation of the forearm in a series of screwdriver tests with 6 varied handles. Consecutively, maximum torque for pronation and supination was determined, submaximum isometric levels of torque were demanded, and, finally, an equal dynamic screwing work for all subjects was simulated. Physiological cost of performance was simultaneously measured by registrations of electromyographic activities (EA) from 4 muscles, which were expected to be involved intensively in screwing tasks. Significant and essential differences between maximum torque values produced by pronation and supination of the right and the left arm of the mainly right-handed subjects were found. For clockwise work, as it is necessary e.g., for driving in screws, inward rotations (pronations) of the nondominant hand are at least as strong as outward rotations of the dominant hand. Differences of about 8% favour of pronations were found. Yet, for counter clockwise work involved e.g., in removing a tightened screw, inward rotations of the dominant hand yielded a much more stronger torque strength than outward rotations of the nondominant hand. Differences of more than 50% right-handed subjects were measured. Also, EA values of the 4 muscles monitored on the right arm differed significantly. Systematically operational and physiological differences due to the varied screwdriver grips, as results of investigations which were not the main objective of the study, corresponded well with the findings of prior studies.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Naoki Enomoto ◽  
Kazuhiko Yamada ◽  
Daiki Kato ◽  
Shusuke Yagi ◽  
Hitomi Wake ◽  
...  

Abstract Background Bochdalek hernia is a common congenital diaphragmatic defect that usually manifests with cardiopulmonary insufficiency in neonates. It is very rare in adults, and symptomatic cases are mostly left-sided. Diaphragmatic defects generally warrant immediate surgical intervention to reduce the risk of incarceration or strangulation of the displaced viscera. Case presentation A 47-year-old woman presented with dyspnea on exertion. Computed tomography revealed that a large part of the intestinal loop with superior mesenteric vessels and the right kidney were displaced into the right thoracic cavity. Preoperative three-dimensional (3D) simulation software visualized detailed anatomy of displaced viscera and the precise location and size of the diaphragmatic defect. She underwent elective surgery after concomitant pulmonary hypertension was stabilized preoperatively. The laparotomic approach was adopted. Malformation of the liver and the presence of intestinal malrotation were confirmed during the operation. The distal part of the duodenum, jejunum, ileum, colon, and right kidney were reduced into the abdominal cavity consecutively. A large-sized oval defect was closed with monofilament polypropylene mesh. No complications occurred postoperatively. Conclusion Symptomatic right-sided Bochdalek hernia in adults is exceedingly rare and is frequently accompanied by various visceral anomalies. Accurate diagnosis and appropriate surgical repair are crucial to prevent possible incarceration or strangulation. The preoperative 3D simulation provided comprehensive information on anatomy and concomitant anomalies and helped surgeons plan the operation meticulously and perform procedures safely.


2020 ◽  
Vol 10 (1) ◽  
pp. 14
Author(s):  
Cezary Grochowski ◽  
Kamil Jonak ◽  
Marcin Maciejewski ◽  
Andrzej Stępniewski ◽  
Mansur Rahnama-Hezavah

Purpose: The aim of this study was to assess the volumetry of the hippocampus in the Leber’s hereditary optic neuropathy (LHON) of blind patients. Methods: A total of 25 patients with LHON were randomly included into the study from the national health database. A total of 15 patients were selected according to the inclusion criteria. The submillimeter segmentation of the hippocampus was based on three-dimensional spoiled gradient recalled acquisition in steady state (3D-SPGR) BRAVO 7T magnetic resonance imaging (MRI) protocol. Results: Statistical analysis revealed that compared to healthy controls (HC), LHON subjects had multiple significant differences only in the right hippocampus, including a significantly higher volume of hippocampal tail (p = 0.009), subiculum body (p = 0.018), CA1 body (p = 0.002), hippocampal fissure (p = 0.046), molecular layer hippocampus (HP) body (p = 0.014), CA3 body (p = 0.006), Granule Cell (GC) and Molecular Layer (ML) of the Dentate Gyrus (DG)–GC ML DG body (p = 0.003), CA4 body (p = 0.001), whole hippocampal body (p = 0.018), and the whole hippocampus volume (p = 0.023). Discussion: The ultra-high-field magnetic resonance imaging allowed hippocampus quality visualization and analysis, serving as a powerful in vivo diagnostic tool in the diagnostic process and LHON disease course assessment. The study confirmed previous reports regarding volumetry of hippocampus in blind individuals.


2020 ◽  
Vol 46 (08) ◽  
pp. 895-907
Author(s):  
Nina D. Anfinogenova ◽  
Oksana Y. Vasiltseva ◽  
Alexander V. Vrublevsky ◽  
Irina N. Vorozhtsova ◽  
Sergey V. Popov ◽  
...  

AbstractPrompt diagnosis of pulmonary embolism (PE) remains challenging, which often results in a delayed or inappropriate treatment of this life-threatening condition. Mobile thrombus in the right cardiac chambers is a neglected cause of PE. It poses an immediate risk to life and is associated with an unfavorable outcome and high mortality. Thrombus residing in the right atrial appendage (RAA) is an underestimated cause of PE, especially in patients with atrial fibrillation. This article reviews achievements and challenges of detection and management of the right atrial thrombus with emphasis on RAA thrombus. The capabilities of transthoracic and transesophageal echocardiography and advantages of three-dimensional and two-dimensional echocardiography are reviewed. Strengths of cardiac magnetic resonance imaging (CMR), computed tomography, and cardiac ventriculography are summarized. We suggest that a targeted search for RAA thrombus is necessary in high-risk patients with PE and atrial fibrillation using transesophageal echocardiography and/or CMR when available independently on the duration of the disease. High-risk patients may also benefit from transthoracic echocardiography with right parasternal approach. The examination of high-risk patients should involve compression ultrasonography of lower extremity veins along with the above-mentioned technologies. Algorithms for RAA thrombus risk assessment and protocols aimed at identification of patients with RAA thrombosis, who will potentially benefit from treatment, are warranted. The development of treatment protocols specific for the diverse populations of patients with right cardiac thrombosis is important.


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