A cross sectional study of prevalence of left, right and mixed handedness was made on 512 Malawian school children (240 boys and 272 girls) aged 6-17 years. Handedness was assessed using questionnaire incorporating questions on hand preferred for eight unimanual activities. Interviews with guardians, pupils and teachers were conducted to assess the pressure experienced by children to use right ...

This study addresses the demands of alternating bimanual syncopation, a coordination mode in which the two hands move in alternation while tapping in antiphase with a metronomic tone sequence. Musically trained participants were required to engage in alternating bimanual syncopation and five other coordination modes: unimanual syncopation where taps are made (with the left or right hand) after ...

In the present study we investigate age-related changes in hand preference for grasping and the influence of task demands on such preference. Children (2-11), young-adults (17-28) and older-adults (57-90) were examined in a grasp-to-eat and a grasp-to-construct task. The end-goal of these tasks was different (eat vs. construct) as was the nature of the task (unimanual vs. bimanual). In both tas...

Handedness development during infancy could be represented as a progressive expansion of a hand-use preference across a wider range of increasingly complex skills. The goal of the present study was to explore the development of role-differentiated bimanual manipulation (RDBM) during infancy as an expansion of the development of handedness for acquiring objects and unimanual manipulation. Infant...

Any task is carried out more successfully if we allocate undivided attention to it, but as demands on attentional capacity increase-for example, in concurrent or dual task conditions-performance on attended tasks becomes more impaired. Patients with schizophrenia show impaired performance on tasks requiring high levels of attentional capacity. This study examines performance of 11 patients with...

The authors explored application of analytical inverse optimization (ANIO) method to the normal finger forces in unimanual and bimanual prehensile tasks with discrete and continuously changing constraints. The subjects held an instrumented handle vertically with one or two hands. The external torque and grip force changed across trials or within a trial continuously. Principal component analysi...

Performing a complex unimanual motor task markedly increases activation not only in the hemisphere contralateral to the task-performing hand but also in the ipsilateral hemisphere. Transcranial magnetic stimulation studies showed increased motor evoked potential amplitude recorded in resting hand muscles contralateral to the task-performing hand during a unimanual motor task, and transcallosal ...

Motor overflow is extraneous movement in a limb not involved in a motor action. Typically, overflow is observed in people with neurological impairments and in healthy children and adults during strenuous and attention-demanding tasks. In the current study, we found that young infants produce vast amounts of motor overflow, corroborating claims of symmetry being the default state of the motor sy...