Motor imagery is a mental rehearsal of simple or complex motor acts without overt body movement. It has been proposed that the association between performance and the mental rehearsal period that precedes the voluntary movement is an important point of difference between highly trained athletes and beginners. We compared the activation maps of elite archers and nonarchers during mental rehearsal of archery to test whether the neural correlates of elite archers were more focused and efficiently organised than those of nonarchers. Brain activation was measured using functional MRI in 18 right-handed elite archers and 18 right-handed nonarchers. During the active functional MRI imagery task, the participants were instructed to mentally rehearse their archery shooting from a first-person perspective. The active imagery condition was tested against the nonmotor imagery task as a control condition. The results showed that the premotor and supplementary motor areas, and the inferior frontal region, basal ganglia and cerebellum, were active in nonarchers, whereas elite archers showed activation primarily in the supplementary motor areas. In particular, our result of higher cerebellar activity in nonarchers indicates the increased participation of the cerebellum in nonarchers when learning an unfamiliar archery task. Therefore, the difference in cerebellar activation between archers and nonarchers provides evidence of the expertise effect in the mental rehearsal of archery. In conclusion, the relative economy in the cortical processes of elite archers could contribute to greater consistency in performing the specific challenge in which they are highly practised.

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The more localized neural activity of elite and expert archers than novices permits greater efficiency in the complex processes subserved by these regions. The elite group's high activity in the cerebellar dentate indicates that the cerebellum is involved in automating simultaneous movements by integrating the sensorimotor memory enabled by greater expertise in self-paced aiming tasks. A companion article comments on and generalizes our findings.

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Wearable fabric-based energy harvesters have continued to gain importance for use in portable consumer electronics as an ecofriendly energy source that is independently self-powered by various activities. Herein, we address the output features of highly flexible Ni-Cu fabric-based triboelectric nanogenerators (F-TENG) employing surface-embossed polydimethylsiloxane (SE-PDMS) layers, as a crucial approach for enhancing power generation. Such SE-PDMS configurations were achieved via control of the ZnO nanowire (NW) and nanoflake (NF) frames initially prepared on bare Ni-Cu fabrics by a hydrothermal approach. The wearable SE-PDMS and Al-evaporated fabrics, respectively, served as triboelectric bottom and top materials in F-TENGs. Along with the structural analyses of the F-TENGs, the enhanced power generation of the F-TENGs was illustrated via the application of periodic mechanical stress using an adjustable bending machine. The present approach may provide a useful and simple route for developing self-powered, wearable, and smart electronics based on fabric substrates.