scholarly journals Laterality Does Not Affect the Depth Perception, but Interpupillary Distance

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Murat Aslankurt ◽  
Lokman Aslan ◽  
Adnan Aksoy ◽  
Murat Özdemir ◽  
Şenol Dane

In this study, which investigates the relationship between the levels of stereopsis with eye and hand dominance or interpupillary distance, 120 healthy young volunteers were investigated. Eye dominance was determined by modified Miles technique following a complete eye examination. Handedness was assessed with the Edinburgh handedness inventory. Interpupillary distance was measured with millimetric ruler. Stereoacuity was measured in both contour (Titmus test) and random dot (TNO test) stereograms. The stereopsis scores were evaluated in terms of hand or eye dominance. The correlation between stereopsis score and interpupillary distance was assessed. Main outcome measures were stereopsis scores according to hand and eye dominance. As a result, right- and left-handed individuals showed no differences in terms of stereopsis. No differences were found in stereopsis scores between right- and left-eye dominant people. There was a correlation between interpupillary distance and the depth of stereopsis (r=-0.248,P<0.05). Contrary to the expectation, the left and right dominant individuals did not differ in levels of stereopsis. Interpupillary distance has a positive effect on stereopsis.

Author(s):  
M. Akif Ziyagil ◽  
Inci Kesilmiş ◽  
Nevzat Demirci ◽  
M. Melih Kesilmiş

This study investigates the effects of ipsilateral and crossed hand-eye dominance on one and both hands catching performance (OHCP and BHCP) in participants aged 10 to 13 years. The combined groups including hand and eye dominance consisted of right handed-right eyed (RHRE), right handed-left eyed (RHLE), left handed-left eyed (LHLE) and left handed-right eyed (LHRE), respectively. In this study the mean values were only higher in the favor of LHLE females in left hand OHCP from 2 and 3 m distances. In other side, LHLE males had a higher mean values not only in left hand OHCP from 2 and 3 meters but also in the right hand OHCP from 3 meters. No significant difference was observed in BHCP among four groups in both genders. In conclusion, ipsilateral handeye dominance is an advantage for OHCP compared to cross dominance. Also left side had an advantage compare to the right side in OHCP. Keywords: Hand dominance; physical activity; gender.


2012 ◽  
Vol 108 (5) ◽  
pp. 1501-1510 ◽  
Author(s):  
Nicole M. Gordon ◽  
Thorsten Rudroff ◽  
Joel A. Enoka ◽  
Roger M. Enoka

The purpose of this study was to compare endurance time and accompanying neuromuscular adjustments when left- and right-handed subjects used the dominant and nondominant arms to sustain submaximal contractions that required either force or position control. Ten left-handed and 10 right-handed healthy adults (21 ± 5 yr) participated in the study. Each subject exerted a similar net torque about the elbow joint during the force and position tasks to achieve a target force of 20% maximal voluntary contraction (MVC) force (56 ± 18 N). MVC force declined to a similar level immediately after task failure for left- and right-handed subjects (27 ± 13 vs. 25 ± 15%, P = 0.9). Endurance time for the position task was similar for the dominant and nondominant arms (task × dominance interaction, P = 0.17). Although the difference in endurance time between the two tasks was similar for left-handed (136 ± 165 s) and right-handed individuals (92 ± 73 s, task × handedness interaction, P = 0.38), there was greater variance in the ratio of the endurance times for the force and position tasks for left-handed (0.77) than right-handed subjects (0.13, P < 0.001; see Fig. 2 ). Furthermore, endurance time for the force and position tasks was significantly correlated for right-handed subjects ( r2 = 0.62, P < 0.001), but not for left-handed subjects ( r2 = 0.004, P = 0.79). Multiple regression analyses identified sets of predictor variables for each endurance time, and these differed with handedness and task. Hand dominance, however, did not influence endurance time for either group of subjects. These findings indicate that endurance times for the elbow flexors when performing submaximal isometric contractions that required either force or position control were not influenced by hand dominance but did depend on handedness.


Author(s):  
Salim A. Mouloua ◽  
Mustapha Mouloua ◽  
Daniel S. McConnell ◽  
P. A. Hancock

Two studies were carried out to examine the effects of user handedness and hand dominance on a motor task using Fitts’ law. Study one was designed to validate our previous findings showing differences between left- and right-handed participants who completed a mouse-pointing task using Fitts’ law. Results showed that right-handed participants were significantly faster than their left-handed peers, thereby validating our previous findings. Study two examined the effect of handedness and hand dominance on motor task performance by requiring two groups of left- and right-handed participants perform the motor task using both their dominant and non-dominant hands. Results showed a significant interaction between handedness and hand dominance on task performance. Right-handed participants were again significantly faster than their left-handed peers when both groups were using their dominant hand. However, left-handed participants were significantly faster than their right-handed peers when both groups were using their non-dominant hand. These findings might be attributed to prior training with computer mice designs that do not account for user handedness. Both theoretical and practical implications, as well as directions for future studies are also discussed.


2021 ◽  
Vol 30 (2) ◽  
pp. 192-204
Author(s):  
Ivanka Asenova ◽  

Cerebral lateralization is associated with differences in brain organization and handedness is seen as its main marker. In order to verify the hypothesis that differences in brain organization tend to be associated with different patterns of interests and abilities, 379 normal left-handed subjects (221 women, aged 18 – 72 years) and 366 normal right-handed subjects (256 women, aged 18 – 72 years) were interviewed about their interests and special abilities. The following interests and special abilities were studied: singing, playing an instrument, dancing, painting, acting, foreign language skills, sports skills, and writing poetry.The results in the left-handers group showed that there is a significantly higher percentage of subjects with a pronounced interest in playing an instrument. In the group of right-handers, the study demonstrated a significantly higher percentage of subjects specifically interested in learning foreign languages. With respect to the abilities, a significantly higher incidence of participants with vocal, instrumental, sports, and foreign language skills was found in the left-handers’ group. Differences in functional cerebral organization between left- and right-handers were suggested as possible explanation for the relationship of handedness with special abilities.


2005 ◽  
Vol 17 (2) ◽  
pp. 262-272 ◽  
Author(s):  
Scott H. Frey ◽  
Margaret G. Funnell ◽  
Valerie E. Gerry ◽  
Michael S. Gazzaniga

The overwhelming majority of evidence indicates that the left cerebral hemisphere of right-handed humans is dominant both for manual control and the representation of acquired skills, including tool use. It is, however, unclear whether these functions involve common or dissociable mechanisms. Here we demonstrate that the disconnected left hemispheres of both right- and left-handed split-brain patients are specialized for representing acquired tool-use skills. When required to pantomime actions associated with familiar tools (Experiment 2), both patients show a right-hand (left hemisphere) advantage in response to tool names, pictures, and actual objects. Accuracy decreases as stimuli become increasingly symbolic when using the left hand (right hemisphere). Tested in isolation with lateralized pictures (Experiment 3), each patient's left hemisphere demonstrates a significant advantage over the right hemisphere for pantomiming tool-use actions with the contralateral hand. The fact that this asymmetry occurs even in a left-handed patient suggests that the left hemisphere specialization for representing praxis skills can be dissociated from mechanisms involved in hand dominance located in the right hemisphere. This effect is not attributable to differences at the conceptual level, as the left and right hemispheres are equally and highly competent at associating tools with observed pantomimes (Experiment 4).


2020 ◽  
Vol 5 (1) ◽  
pp. 52
Author(s):  
Sukirno Sukirno

Abstract This study aims to empirically challenge the moderation of Non-Performing Loans to the effect of Credit Distribution Rates on Profitability. The population of 81 bank companies listed on the Indonesia Stock Exchange in the period 2014-2018 and which met the criteria of the research sample (purposive sampling) were 22 companies. The research method uses survey methods with quantitative research approaches, the analytical tool used is moderation regression. This study concludes that the level of credit distribution has a significant positive effect on profitability and the existence of the problem loan variable is proven to be a moderating variable that weakens the relationship between the level of credit distribution and profitability.    


1997 ◽  
Vol 36 (4II) ◽  
pp. 855-862
Author(s):  
Tayyeb Shabir

Well-functioning financial markets can have a positive effect on economic growth by facilitating savings and more efficient allocation of capital. This paper characterises some of the recent theoretical developments that analyse the relationship between financial intermediation and economic growth and presents empirical estimates based on a model of the linkage between financially intermediated investment and growth for two separate groups of countries, developing and advanced. Empirical estimates for both groups suggest that financial intermediation through the efficiency of investment leads to a higher rate of growth per capita. The relevant coefficient estimates show a higher level of significance for the developing countries. This financial liberalisation in the form of deregulation and establishment and development of stock markets can be expected to lead to enhanced economic growth.


2018 ◽  
Vol 9 (2) ◽  
pp. 18-32
Author(s):  
Andy Mulyana ◽  
Devi Ayuni

This study aims to evaluate the role of satisfaction and commitment as mediating the effect of service quality on student loyalty as the user of Open University's Online Tutorial. Based on data analysis on student of Management program 229 as respondents with Structural Equation Modeling (SEM), this study found the relationship between: (1) positive influence of service quality to satisfaction and loyalty of students using tuton; (2) the positive effect of satisfaction on student loyalty using tuton; (3) satisfaction is a mediator between service quality and loyalty of students using tuton. Conversely, commitment has no positive effect on student loyalty as a tuton user. In addition, commitment does not mediates the effect of satisfaction on the loyalty of tuton users. Keywords: service quality, satisfaction, commitment, loyalty


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alicja Kowalczyk ◽  
Elżbieta Gałęska ◽  
Ewa Czerniawska-Piątkowska ◽  
Anna Szul ◽  
Leszek Hebda

AbstractThe aim of this study was to analyze the relationship between the concentration of hormones in the seminal plasma, the bull maintenance system in the insemination station, and the regularity of sperm donation and the response to the phantom (libido level). An additional goal was to determine whether there is a relationship between the hormonal profile in the blood, the sperm plasma, the oxidative and antioxidant profile in the blood of bulls and the biometry of their testicles and scrotum, as well as the quality of their sperm in both different seasons and intensities of reproductive use. For the study, 220 healthy and sexually mature Polish Holstein–Friesian bulls were used. They all had normal libido and were fed equally. The animals were grouped according to the scheme: young (16–20 month/n = 60) and old (26–30 month/n = 60) including: individually housed (n = 30) and group housed (n = 30) young, old individually housed (n = 30) and group housed (n = 30) (n total animals = 120); young animals donating semen once a week (every Thursday) (n = 25) and sporadically (once every two months on a random day of the week) (n = 25), old animals donating semen once a week (every Thursday) (n = 25 ) and sporadic donors (once every two months on a random day of the week) (n = 25) (n total animals = 100). When analyzing the results of this study, it should be stated that regular use has a positive effect on the secretion of sex hormones in bulls. Higher levels of testosterone and lower levels of estradiol and prostaglandins resulted in higher sexual performance, expressed by a stronger response to the phantom. The differences in favor of regular use were independent of the bull's age. The results of our research illustrate that the quality of semen and its freezing potential may depend on the season and frequency of its collection, as well as on the age of the males.


2021 ◽  
pp. 112067212199104
Author(s):  
Giuseppe D’Amico Ricci ◽  
Claudia Del Turco ◽  
Elena Belcastro ◽  
Marco Palisi ◽  
Mario R Romano ◽  
...  

Purpose: Although acute conjunctivitis has been listed from the beginning as a possible sign of COVID-19, the likelihood of this association remains unclear. The aim of this study was to investigate the relationship between COVID-19 and conjunctivitis. Methods: In this retrospective, observational study, we recruited all patients with signs and symptoms of acute conjunctivitis seen at the Eye Emergency Department (ED), Turin Eye Hospital, between 01/01/2020 and 12/05/2020 and cross-checked our data with the Piedmont Region online COVID-19 registry in the same period. Results: Among 10,065 patients seen at our ED during the timespan considered, 88 underwent a nasopharyngeal swab (NS) for SARS-CoV-2 detection within 4 weeks before/after our examination. On average, NS was performed −0.72 ± 1.8 weeks before/after eye examination. Of the 77 patients with a negative NS, 26 (33.8%) had a diagnosis of acute conjunctivitis, whereas the remaining 51 (66.2%) had other eye disorders. Among the 11 patients with COVID-19, 7 (63,6%) had a diagnosis of acute conjunctivitis. We found a non-statistically significant increase in NS positivity rate (21.2%) among cases examined at our ED for acute conjunctivitis, compared to the NS positivity rate (7.3%) in patients examined for all other eye conditions ( p = 0.092). The Odds Ratio of having a positive NS in patients with acute conjunctivitis was 3.43 (95% I.C. = 0.9–12.8, p = 0.06). Considering online-registry data of Turin population during the same time-span, among 2441 positive NS cases only 27 (1.1%) presented with acute conjunctivitis. Conclusion: Our results do not reveal a statistically significant correlation between COVID-19 and acute conjunctivitis. Synopsis The present study analyzes retrospectively data from a tertiary eye referral center to investigate the relationship between COVID-19 infection and conjunctivitis.


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