Hand Preference and Creativity of Papua University Student

Human has a preference to use their hands for various manual activities. Left-handed preference is people who tend to use their left hand to perform various manual activities, while right-handed people tend to use right-handed. Any researches show that the left-handed preference for more creativity was influenced by the dominant use of the right brain and bigger corpus callosum. The research aims to determine the percentage of left-handed preference and their creativity in Universitas Papua, Manokwari Papua Barat. The method used in this research is the descriptive method. Data collection used a questionnaire to evaluate individual hand preference using Handedness Questionnaire and to determine individual creativity using Adjective Check List. The percentage of left-handed people in UNIPA were 9.3% or lower than right-handed and higher than ambidextrous. Our study supports the statement about selection in handedness in the traditional society which showed a higher percentage of left-hander as advantages related to using hand intensively. The percentage of left-handed males and females was almost equal and strongly left-handed was higher in females. The percentage of creative people was higher in left-handed, especially in males

The evolution and biological correlates of hand preferences in anthropoid primates

The evolution of human right-handedness has been intensively debated for decades. Manual lateralization patterns in non-human primates have the potential to elucidate evolutionary determinants of human handedness. However, restricted species samples and inconsistent methodologies are limiting comparative phylogenetic studies. By combining original data with published literature reports, we assembled data on hand preferences for standardized object manipulation in 1,806 individuals from 38 species of anthropoid primates, including monkeys, apes, and humans. Based on that, we employ quantitative phylogenetic methods to test prevalent hypotheses on the roles of ecology, brain size and tool use in primate handedness evolution. We confirm that human right-handedness represents an unparalleled extreme among anthropoids and found taxa displaying significant population-level handedness to be notably rare. Species-level direction of manual lateralization was largely uniform among non-human primates and neither correlated with phylogeny nor with any of the selected biological predictors. In contrast, we recovered highly variable patterns of hand preference strength, which show signatures of both ecology and phylogeny. In particular, terrestrial primates tend to display weaker hand preferences than arboreal species. These results challenge popular ideas on primate handedness evolution, especially the postural origins hypothesis. Furthermore, they point to a potential adaptive benefit of disparate lateralization strength in primates, a measure of hand preference that has often been overlooked in the past. Finally, our data show that human lateralization patterns do not align with trends found among other anthropoids, suggesting that unique selective pressures gave rise to the unusual hand preferences displayed by our species.

Age and Not the Preferred Limb Influences the Kinematic Structure of Pointing Movements

In goal-directed movements, effective open-loop control reduces the need for feedback-based corrective submovements. The purpose of this study was to determine the influence of hand preference and aging on submovements during single- and two-joint pointing movements. A total of 12 young and 12 older right-handed participants performed pointing movements that involved either elbow extension or a combination of elbow extension and horizontal shoulder flexion with their right and left arms to a target. Kinematics were used to separate the movements into their primary and secondary submovements. The older adults exhibited slower movements, used secondary submovements more often, and produced relatively shorter primary submovements. However, there were no interlimb differences for either age group or for the single- and two-joint movements. These findings indicate that open-loop control is similar between arms but compromised in older compared to younger adults.

Differential Ageing of the Brain Hemispheres: Evidence from a Longitudinal Study of Hand Preferences in Common Marmosets

This paper is concerned with decreasing asymmetry of motor control in ageing. It discusses age-related changes in humans and reports a longitudinal study of hand preferences in common marmosets. An annual assessment of hand preference for holding food was recorded throughout the lifespan of 19 marmosets that lived for at least 9 years, and half of those lived for at least 11 years. Those with a left-hand preference showed a gradual reduction in the strength of their hand preference throughout adult life. No significant change in the strength of hand preference was found in right-handed marmosets. Hence, ageing has a specific effect on motor control by the right hemisphere.

Handedness and midsagittal corpus callosum morphology: a meta-analytic evaluation

Following a series of seminal studies in the 1980s, left or mixed hand preference is widely thought to be associated with a larger corpus callosum than right handedness, influencing the interpretation of findings and various theories related to interhemispheric processing, brain lateralisation, and hand preference. Recent reviews, however, find inconsistencies in the literature and cast doubt on the existence of such an association. The present study was conducted to clarify the relationship between hand preference and callosal morphology in a series of meta-analyses. For this purpose, articles were identified via a search in PubMed and Web Of Science databases. Studies reporting findings relating to handedness (assessed as hand preference) and corpus-callosum morphology in healthy participants were considered eligible. On the basis of a total of k = 24 identified studies and databases, random-effects meta-analyses were conducted considering four different group comparisons: (a) dominantly right- (dRH) and left-hand preference (dLH), (b) consistent right (cRH) and non-cRH preference, (c) cRH with mixed-hand preference (MH), and (d) cRH with consistent left-hand hand preference (cLH). For none of these meta-analyses did we find a significant effect of hand preference, and narrow confidence intervals suggest that the existence of population effects larger than 1% explained variance could be excluded. For example, considering the comparison of dRH and dLH (k = 14 studies; 1910 dRH and 646 dLH participants) the mean effect size was Hedge’s g = 0.016 (95% confidence interval: − 0.12 to 0.15; explained variance: < 0.001%). Thus, the common practice of assuming an increase in callosal connectivity based on mixed or left hand preference is likely invalid.

Left-Handedness in Obstetrics and Gynecology: A Nationwide Survey of U.S. Trainees and Educators

Objective This study aimed to evaluate the views and influence of left-handedness among obstetrics and gynecology (OBGYN) trainees and educators and to identify perceived obstacles in training by left-handed (LH) trainees. Study Design An online survey was sent to the U.S. Obstetrics and Gynecology training programs. All participants were asked questions on hand preference for various medical and nonmedical activities, as well as on demographics. Participant responses to handedness and their role as a learner or educator directed them toward further questions. Trainees were surveyed on their experience and outlook as a LH physician in OBGYN. Educators were surveyed on their experience and attitudes in working with LH trainees. LH educators were also surveyed on their experience as a LH physician, similar to the LH trainees. Chi-square or Fisher's exact analysis was used as appropriate, with p-value <0.05 considered statistically significant. Results Responses were received from 21 training programs, totaling 304 individuals. Participants included 205 learners (156 right handed and 49 left handed), and 99 faculty (82 right handed and 17 left handed). A lack of LH surgical instrument availability (93.6%) and difficulty using right-handed (RH) instruments (83%) were notable obstacles reported by LH learners. The majority of LH learners (57.4%) did not consider their handedness to be disadvantageous but did note added difficulty when training under RH mentors when compared with training under LH mentors (66%). In contrast to LH educators, RH educators endorsed added difficulty in instructing operative procedures to LH learners (32.1 vs. 13.3%, p = 0.012). Conclusion LH trainees face unique challenges during their OBGYN training. Educators would benefit from guidance on how best to manage these trainees. Educators should work to adapt surgical and procedural techniques to accommodate LH trainees. Key Points

Handedness and its genetic influences are associated with structural asymmetries of the cerebral cortex in 31,864 individuals

Roughly 10% of the human population is left-handed, and this rate is increased in some brain-related disorders. The neuroanatomical correlates of hand preference have remained equivocal. We resampled structural brain image data from 28,802 right-handers and 3,062 left-handers (UK Biobank population dataset) to a symmetrical surface template, and mapped asymmetries for each of 8,681 vertices across the cerebral cortex in each individual. Left-handers compared to right-handers showed average differences of surface area asymmetry within the fusiform cortex, the anterior insula, the anterior middle cingulate cortex, and the precentral cortex. Meta-analyzed functional imaging data implicated these regions in executive functions and language. Polygenic disposition to left-handedness was associated with two of these regional asymmetries, and 18 loci previously linked with left-handedness by genome-wide screening showed associations with one or more of these asymmetries. Implicated genes included six encoding microtubule-related proteins: TUBB, TUBA1B, TUBB3, TUBB4A, MAP2, and NME7—mutations in the latter can cause left to right reversal of the visceral organs. There were also two cortical regions where average thickness asymmetry was altered in left-handedness: on the postcentral gyrus and the inferior occipital cortex, functionally annotated with hand sensorimotor and visual roles. These cortical thickness asymmetries were not heritable. Heritable surface area asymmetries of language-related regions may link the etiologies of hand preference and language, whereas nonheritable asymmetries of sensorimotor cortex may manifest as consequences of hand preference.

Hand Preference in Adults’ Referential Gestures during Storytelling: Testing for Effects of Bilingualism, Language Ability, Sex and Age

Previous studies have shown that gestures are mediated by the left hemisphere. The primary purpose of this study was to test whether most gestures are also asymmetrical, i.e., produced with the right hand. We also tested four predictors of the degree of right-hand gesture use: bilingualism, language ability, sex, and age. These factors have been related to differences in the degree of language lateralization. English monolinguals, French–English bilinguals, and French monolinguals watched a cartoon and told the story back. For the gestures they produced while speaking, we calculated the percentage produced with the right hand. As predicted, the majority of gestures were right-handed (60%). Bilingualism, language ability, and age were not significantly related to hand choice in either English or French. In English, males tended to produce more right-handed gestures than females. These results raise doubts as to whether hand preference in gestures reflects speech lateralization. We discuss possible alternative explanations for a right-hand preference.