Effect Of Hand Preference Research Articles

The Effects of Hand Preference on Measures of Psychological Well-Being in a Sample of Older Adults in the Kingdom of Saudi Arabia.

Generally, being left-handed has been linked to poorer mental health and quality of life. However, given that few studies have investigated these links in Saudi Arabia and that the prevalence of mental illness in the general population is rising, it is important to explore whether left-handedness can be considered a risk factor in a sizable, general population. To investigate whether left-handers experience psychological well-being or good quality of life. A cross-sectional study among adults in Saudi Arabia was conducted from March 6, 2022to February 27, 2023. The study included (N = 2862) respondents who met the inclusion criteria, with an average age of 28.95 years. Left-handed individuals made up 31.7%, whereas right-handed individuals made up 60.3%, and ambidextrous individuals made up 7.9% of the population. Using the Mental Health Quality of Life questionnaire (MHQoL-7D) scoring manual, the quality of life for both left-and right-handers was evaluated. Those who were right-handed had a higher quality of life than those who were left-handed. Multivariate Analysis of Variance (MANOVA) was conducted, and the findings showed that neither the left-handed nor the right-handed group significantly differed in their levels of poor quality of life or psychological well-being. Using the left or the right hand had no effect on one's quality of life or degree of well-being. Further studies with a larger sample size are needed to examine this result in more detail.

Handedness, intelligence, visual-perceptual and motor functions in young adults

This study was conducted to investigate intelligence and visual-perceptual and motor functions in relation to hand dominance and the moderating role of gender and in young adults. The participants included 120 left-handed and right-handed individuals. A demographic questionnaire, the Wechsler Adult Intelligence Scale-Revised (WAIS-R) and the Bender-Gestalt II (BGT-II) were used for data gathering in this study. Analysis did not show any significant differences between left-handed and right-handed individuals in intelligence, performance and both recall and motor subscales of BGT-II in the present study. Findings showed significant group differences for the copy and the perceptual subscales of BGT-II in these samples. Left-handed individuals had significantly higher scores than right-handed individuals in the copy and the perceptual subscales of BGT-II. Also, there were no significant differences between males and females on the WAIS-R and all subscales of the BGT-II in this study. This study indicated the different effect of hand preference in intelligence and visual-perceptual and motor functions among young adults with the moderating role of age.

The effect of hand preference on skeletal asymmetry in human limbs

The study of asymmetry offers valuable insight into the biomechanical factors, such as hand preference, that influence development of the human body. Previous studies of human skeletal asymmetry often lack known handedness data and tend to presume right‐handedness without specifically analyzing upper limb elements. Here, we investigate differences in individual asymmetry (IA) in elements of the upper limb (i.e. humerus, radius) and lower limb (i.e. femur, tibia) from a modern sample of 40 males and females for whom hand preference was documented. The shape of these four bones was quantified using landmark configurations on 3D bone models. All possible distances between landmarks were calculated for the left and right sides of each bone and were used to calculate average IA for each individual bone. The results found that IA for the four bones was only correlated between the humerus and radius (r = 0.33, p = 0.038), suggesting that the upper limb does not always correlate with the lower limb as previously thought. Kruskal‐Wallis and Mann‐Whitney U tests found no significant differences in IA across sex or handedness groups for the limb bones but left‐handed males and females had higher left‐side dominance in the radius and tibia as compared to right‐handed individuals. Thus, the results suggest that handedness can affect asymmetry in the lower limb. Further addition of specimens, particularly left‐handed individuals, will elucidate the relative effects of handedness in shaping human skeletal asymmetry patterns.Support or Funding InformationThis was supported by funding from the Wenner‐Gren Dissertation Fieldwork Grant (Grant #9641), the Mark Diamond Research Fund (SP‐18‐19), and the 2017 Morris E. and Lucille R. Opler Dissertation Research Scholarship.

Age-Related Differences in Peak Handgrip Strength Between Wrestlers and Nonathletes During the Developmental Years

This study examined the development of peak handgrip strength from childhood to adulthood in wrestlers (n = 122) and nonathlete controls (n = 122). The effect of hand preference on handgrip strength and the relationship of anthropometrical characteristics with handgrip strength in wrestlers and controls were also evaluated. Participants were assigned into age groups: children, young adolescents, late adolescents, and adults. Body height and mass, hand dimensions (length, span, and width), and absolute handgrip (in kilograms) were measured. Handgrip strength was similar in wrestlers and controls in the younger age groups (i.e., in children and young adolescents), whereas late adolescent and adult wrestlers exhibited significantly greater peak handgrip strength (p < 0.05) than their control peers. Nonathletes older than 15 years demonstrated an approximately 10% greater peak handgrip strength (p < 0.05) with their preferred hand compared with the nonpreferred hand. In contrast, late adolescent and adult wrestlers exhibited similar handgrip strength with both hands. Peak handgrip strength exhibited a significant linear correlation with all the anthropometric measures examined; however, a higher percentage in the variation in peak handgrip strength was explained by body height and hand length than the other anthropometric variables in both groups. In conclusion, wrestlers exhibit a sport-specific pattern of handgrip strength changes during the developmental years. Body height and hand length exhibited the strongest correlations with handgrip strength during the developmental years in wrestlers and in controls. The training adaptations of wrestling resulted in symmetrical handgrip strength development in both hands at late adolescence and adulthood. These data serve to provide a descriptive profile of handgrip strength in wrestlers, to assist both coaches and health professionals for talent selection and/or development of training programs for performance enhancement and rehabilitation.

The Effects of Hand Preference on Attention

Handedness is associated with cerebral hemispheric differences. Normal patterns of brain asymmetries are needed for the neural processing of attention. In order to identify ADHD (Attention Deficit Hyperactive Disorder) children, the use of checklists allows a greater level of accuracy. Here, we will review our data on this subject. Our first study investigated the psychometric properties of a scale developed to assess attention disorders. Our second study investigated the relationship between handedness and attention disorders using the factors derived from the scale. Our third study included the use of a continuous visual test of attention (CVAT) and examined the relationship between handedness and CVAT variables. For the first and second study, 239 students were included. From this sample, 42 students were selected to participate in the third study. Forty-five teachers rated the children. Four factors were extracted: hyperactivity/impulsivity (explained variance = 36.3%); inattention (11.4%); social isolation (5.2%) and self-confidence (explained variance = 3.3%). Sixty-eight children were included in the ADHD group. We found a higher number of consistent left-handers in the ADHD group as compared to the normal group and a significant effect of handedness on factor hyperactivity/impulsivity. This indicated that left-handers showed greater problems in the hyperactivity-impulsivity domain as compared to right-handers. Considering the data derived from CVAT, a significant handedness effect was found only for the variable commission errors. Left-handers with attention problems showed the greatest number of errors and normal dextrals the lowest number of errors. Normal left-handers made significantly more errors than normal dextrals. Commission error is a parameter that is commonly viewed as a measure of impulsivity. Our data show that hyperactivity/impulsivity is related to handedness, because left-handers present more problems in impulsive behavior than right-handers and suggest that consistent left-handed subjects show greater probability to develop ADHD as compared to right-handed subjects.

Left-Handedness and Male-Male Competition: Insights from Fighting and Hormonal Data

Male-male competition can shape some behavioral or morphological traits of males. Here we investigate if this competition could play a role in the persistence of the polymorphism of handedness in human populations. A negative frequency-dependent selection mechanism has been hypothesized, based on the fact that left-handed men may benefit from a "surprise" advantage during fighting interactions because they are rare in human populations. This advantage may thereby enhance the probability of survival of left- handed men and/or their reproductive success through an increase in social status. In this study, we first explored the association between hand preference and lifetime fighting behavior in a population of 1,161 French men. No effect of hand preference on the probability of fighting was detected, suggesting that the innate propensity to fight does not differ between left- and right-handers. However, among men who had been involved in at least one fight during their lifetime, left-handers reported significantly more fights than right-handers. To explore the biological basis of this behavior, we also investigated the testosterone concentration in saliva samples from 64 French university students. Consistent with frequencies of fights, we found a significantly higher average testosterone concentration in left-handers than in right-handers. We suggest that these behavioral and hormonal differences may be acquired throughout life due to previous experiences in a social context and may favor the persistence of left-handers in humans.

A new means of measuring index/ring finger (2D:4D) ratio and its association with gender and hand preference

Relative finger length can predict a person's gender or their hand preference. We measured finger length using a new “tubes” test, which required participants to slide a clear plastic tube over their fingers and read the length from an attached mm scale. Data collected from 600 students demonstrated that the right fingers are longer than the left for dextrals, but not for non-dextrals. Examination of the relative length of the index and ring fingers revealed a clear gender effect. There was also an effect of hand preference on index/ring finger ratio whereby non-dextrals showed a more masculine pattern compared to dextrals. For non-dextrals, prenatal exposure to high testosterone levels may have caused both a shift away from dextrality and a more masculine pattern of finger ratio. In the second experiment, finger length was measured by the tubes test and by photocopying the hands in 124 undergraduates. The tubes test yielded a longer estimate of ring finger length compared to the photocopy method. Despite this, there was a strong correlation between the tests and both showed an association with gender. Finally, test–retest scores for 45 participants showed a high level of reliability for absolute and relative finger measures. We conclude that the tubes technique provides an effective and easy-to-use means of measuring finger length, which can be administered in a classroom setting.

Left‐ and right‐handed children's drawing performance: Is there any difference?

The aim of the present study was to investigate the effect of hand preference on children's drawing development. An equal number of left‐ and right‐handed children (N = 182), aged 7 to 12 years were asked to complete four different drawing tasks. During the drawing process, directionality of horizontal, vertical, and circular strokes as well as sequencing was recorded. Each drawing was scored according to the developmental stage to which is corresponded. It was found that drawing performance improved with age, irrespectively of hand preference and sex. In other words, left‐ and right‐handers' drawing performance across the four tasks was not found to differ significantly. The only consistent difference between the two groups involved was in the production of horizontal lines. The results are discussed in terms of implications for questions about the lack of differences in left‐ and right‐handed children's drawing performance.

The effect of hand preference on hand anthropometric measurements in healthy individuals

This study was planned for the purpose of investigating the effect of hand preference on hand anthropometric measurements, with the participation of 393 healthy university students. The hand preference direction of the subjects was established according to the Edinburgh Inventory, and five hand preference determination groups were constituted after calculation of the laterality score. During performance of the hand anthropometric measurements, values for both hands were calculated, and seven parameters were evaluated for each hand. Hand width and shape index were found to be high for the right hand, but the palmar length/width ratio was found to be high for the left hand, for strong and weak right handers, respectively. No significant statistical values were obtained among ambidextrous subjects, although their parameters resembled these groups' values. Additionally, in the left-handed group, reverse direction asymmetric values were established, but significant statistical values were not obtained. An increase in right and left hand asymmetry was established going from the strong right hand preferent group to the strong left hand preferent group (on a decreasing scale of right hand preference). If the laterality score is evaluated without regard to groups, left hand shape index and right hand finger index may be accepted as phenotype indicators of hand preference. Left hand shape index and right hand finger index increased in correlation with the tendency for left hand and right hand preference, respectively. The findings reveal that, environmental factors such as hand activity, hormones, and brain asymmetry may play a role in the effect of hand preference on hand anthropometric measurements. In our study, we found no difference in asymmetry in regard to the sex of the subjects, generally.

The effects of hand preference and gender on finger tapping performance asymmetry by the use of an infra-red light measurement device

We used an infra-red device to study the effects of gender and handwriting preference on manual asymmetry in tapping rate and intertap variability. Our sample ( n=102) consisted of approximately equal number of subjects with respect to gender (52 women and 50 men) and handedness (52 right-handers and 50 left-handers). Data on overall performance indicated that men performed more quickly and regularly than women. The index used for measuring manual asymmetry was the difference between the hands as a proportion of the total. Therefore, the asymmetry index was adjusted to remove the influence of overall performance. The analyses based on asymmetry scores indicated a significant handedness effect: right-handers showed greater manual asymmetries than left-handers for both tapping rate and intertap variability. In addition, right handers exhibited a significant greater asymmetry for intertap variability than tapping rate. Taken together, these data may reflect greater hemispheric differences in right-handers, specially for intertap variability.

The Effect of Hand Preference on Hearing Sensitivity: Right Ear Advantage in Right-Handed and Left Ear Advantage in Left-Handed Subjects in Humans

In this study right and left ear hearing times were assessed in high school students divided into various groups according to sex and hand preference. Edirtburg handedness inventory was used to determine hand preference. A tuning fork with 128 Hz frequency and a digital chronometer was used to assess hearing time. Hearing time was found longer in right ear than in left ear in right-handed subjects, whereas it was found longer in left ear than in right ear in left-handed ones. it was found that right handers had right ear advantage according to left handers. However, there was no difference between right- and left-handed subject in left ear hearing time. There was also no difference between girls and boys neither in right ear nor in Jeft ear hearing time. These findings haye shown that hand preference affects hearing sensitivity, but sex has no effect on it .

Hand Preference and Difference Patterns Using the Available Motions Inventory (AMI)

Previous literature in the area of hand preference and performance difference using a variety of tasks were analyzed. There is a clear need for assessing hand preference with an objective and quantitative task performance system which is industrially relevant. The Available Motions Inventory (AMI) was administered to 80 subjects with a computerized data acquisition system. Hand preference was established using normalized AMI subtest scores. An analysis of variance was performed to detect the effects of hand preference and gender on the AMI subtest scores. Subsequently, t-test and correlation analyses were used to further analyze the differential effects of hand preference and gender on the AMI subtest scores and subtest categories.