Constraints on hand-foot coordination associated with phase dependent modulation of corticospinal excitability during motor imagery.

Interlimb coordination involving cyclical movements of hand and foot in the sagittal plane is more difficult when the limbs move in opposite directions compared with the same direction (directional constraint). Here we first investigated whether the directional constraint on hand-foot coordination exists in motor imagery (imagined motion). Participants performed 10 cyclic coordinated movements of right wrist flexion-extension and right ankle dorsiflexion-plantarflexion as quickly and precisely as possible, in the following three conditions; (1) actual movements of the two limbs, (2) imaginary movements of the two limbs, and (3) actual movement of one limb combined with imaginary movement of the other limb. Each condition was performed under two directions; the same and the opposite direction. Task execution duration was measured as the time between the first and second press of a button by the participants. The opposite directional movement took a significantly longer time than did the same directional movement, irrespective of the condition type. This suggests that directional constraint of hand-foot coordination occurs even in motor imagery without actual motor commands or kinesthetic signals. We secondarily examined whether the corticospinal excitability of wrist muscles is modulated in synchronization with an imaginary foot movement to estimate the neural basis of directional constraint on imaginary hand-foot coordination. The corticospinal excitability of the forearm extensor in resting position increased during dorsiflexion and decreased during plantarflexion similarly in both actual and imaginary foot movements. This corticospinal modulation depending on imaginary movement phase likely produces the directional constraint on the imaginary hand-foot coordination.

Difference in Activity in the Supplementary Motor Area Depending on Limb Combination of Hand-Foot Coordinated Movements.

Periodic interlimb coordination shows lower performance when the ipsilateral hand and foot (e.g., right hand and right foot) are simultaneously moved than when the contralateral hand and foot (e.g., right hand and left foot) are simultaneously moved. The present study aimed to investigate how brain activity that is related to the dependence of hand-foot coordination on limb combination, using functional magnetic imaging. Twenty-one right-handed subjects performed periodic coordinated movements of the ipsilateral or contralateral hand and foot in the same or opposite direction in the sagittal plane. Kinematic data showed that performance was lower for the ipsilateral hand-foot coordination than for the contralateral one. A comparison of brain activity between the same and opposite directions showed that there was a greater activation of supplementary motor area for ipsilateral hand-foot coordination as compared to that seen during contralateral hand-foot coordination. We speculate that this might reflect a difference in the degree of inhibition of the neural circuit that disrupts opposite directional movements between ipsilateral and contralateral hand-foot coordinated movements.

[Vaccination coverage of foreign children and their parents' views on immunization services in Gunma Prefecture, Japan].

OBJECTIVES: The aim was to evaluate vaccination coverage among foreign children living in an urban area of Gunma Prefecture, Japan and to examine their parents' views concerning the local immunization services. METHODS: A total of 321 foreign children aged 6 to 18 years in five international schools participated in school health examinations and provided vaccination information. Among the parents, 304 completed a questionnaire on their views about the immunization services. Another questionnaire survey was conducted in nursery schools for parents of 4629 Japanese children aged 0 to 6 years. Of the total, 3811 (82.3%) responded, and 2911 questionnaires answered by the parents who had children aged 3 years and older were eligible for the analysis. RESULTS: The study found a vaccination coverage of 86.2% for diphtheria and tetanus toxoids and pertussis (DTP), 86.5% for poliovirus vaccine, and 87.7% for BCG among the foreign children. Of their parents, 84% were born in Brazil. One third of the foreign children vaccinated for DTP, poliovirus and/or BCG had received each vaccine in Japan, while the others children had been vaccinated in their home countries. Among 162 parents with children immunized in Japan, 77% received the necessary information about immunization services from the local municipal office, and 80% had no major problems. However, 15% felt the language barrier. Among the Japanese children, non-vaccination rates for DTP, poliovirus vaccine, and BCG were 18.5%, 9.9%, and 3.5%, respectively. Of the Japanese parents, 85% knew immunization schedules from the municipal office, and 51% asked for night-time and holiday vaccination sites. CONCLUSION: These results suggest that vaccination coverage for DTP, poliovirus vaccine or BCG is relatively high among foreign children living in Japan. To promote higher rates of vaccination for those residents, however, accessibility of the municipal consultation services in foreign languages should be im-proved.