The evolution of handedness in human populations has intrigued scientists for decades. However, whether handedness really affects Darwinian fitness is unclear and not yet studied in a non-industrial society where selection pressures on health and handedness are likely to be similar to the situation in which handedness has evolved. We measured both hand preference and asymmetry of hand skill (sp...

OBJECTIVE This study aimed to investigate the differences in brain morphology according to handedness. MATERIALS AND METHODS Forty-two healthy subjects were enrolled (21 right-handers and 21 nonright-handers). The two groups were classified according to the Edinburgh Handedness Inventory. Measures of cortical morphology, such as thickness, surface area, volume, and curvature, and the volumes ...

The evolutionary origins of human right-handedness remain poorly understood. Some have hypothesized that tool use served as an important preadaptation for the eventual evolution of populationlevel right-handedness. In contrast, others have suggested that complex gestural and vocal communication served as prerequisite for the evolution of human right-handedness. In this study, we tested these co...

Motor system organization varies with handedness. However, previous work has focused almost exclusively on direction of handedness (right or left) as opposed to degree of handedness (strength). In the present study, we determined whether measures of interhemispheric interactions and degree of handedness are related to contra- and ipsilateral motor cortical representations. Participants complete...

Objectives: The present study aimed to investigate the possible effects of laterality and handedness on higher-order sensory functions and manual dexterity of the elderly. Methods: In this non-experimental cross-sectional study, 58 elderly people aged 60-75 years (35 right-handed) were recruited through a convenience sampling method. Laterality of the selected subjects was examined using the E...

45 Human hands are architecturally symmetrical, yet distinctly different in their functional abilities. This seemingly unique human tendency to use the right hand rather than the left for fine motor function is observed in ~90% of the human population. The remaining ~10% are atypical (i.e. left-handers). In addition to clearly visible hand dominance in humans, there are other behavioural latera...

the aim of this study was to evaluate the effect of handedness and two practice types (explicit vs. implicit) on motor sequence learning. 60 girls (age range of 14 – 17 years old) were randomly assigned to four groups according to their handedness: right–handed-explicit, right–handed–implicit, left–handed-explicit, and left–handed-implicit. participants’ task was accuracy and time of sequential...

OBJECTIVES The fall in the prevalence of left handedness with age has been attributed to either premature mortality or a cohort effect of forced dextrality. Evidence for forced dextrality was sought to differentiate between these competing theories. DESIGN 6097 Edinburgh handedness inventories were used to calculate laterality quotients (LQ) with and without the questions relating to writing ...

It is widely know that the pattern of human handedness is such that approximately 90% of the population is right handed with the remainder being left handed, at least in the adult population. What is less well understood is how handedness develops and at what age adult-like handedness patterns emerge. Quantified in terms of both preference and performance, a plethora of different behavioral ass...