Effect of focus of attention and age on motor acquisition, retention, and transfer: a randomized trial.

BACKGROUND AND PURPOSE: Adult participants benefit more from external focus than internal focus when learning a new motor skill. Because learners from different age groups use different learning strategies, the purpose of this study was to investigate whether the effect of attention focus varies among children and adults. SUBJECTS AND METHODS: Thirty-four children and 32 adults were randomly assigned to internal or external focus-of-attention practice groups. Throwing darts toward a static target, participants performed 50 acquisition trials, 20 retention trials, and 20 transfer trials. RESULTS: The results indicate that focus of attention varies between children and adults in accuracy and variability in the acquisition phase and in accuracy in the transfer phase. No interactions were found in the retention phase. DISCUSSION AND CONCLUSION: The findings suggest that external focus is more effective than internal focus in adults; therefore, physical therapists should instruct adult clients to focus their attention externally to facilitate motor learning. Physical therapists working with children should perhaps direct the client's attention internally; however, further study is needed.

Rose scent: genomics approach to discovering novel floral fragrance-related genes.

For centuries, rose has been the most important crop in the floriculture industry; its economic importance also lies in the use of its petals as a source of natural fragrances. Here, we used genomics approaches to identify novel scent-related genes, using rose flowers from tetraploid scented and nonscented cultivars. An annotated petal EST database of approximately 2100 unique genes from both cultivars was created, and DNA chips were prepared and used for expression analyses of selected clones. Detailed chemical analysis of volatile composition in the two cultivars, together with the identification of secondary metabolism-related genes whose expression coincides with scent production, led to the discovery of several novel flower scent-related candidate genes. The function of some of these genes, including a germacrene D synthase, was biochemically determined using an Escherichia coli expression system. This work demonstrates the advantages of using the high-throughput approaches of genomics to detail traits of interest expressed in a cultivar-specific manner in nonmodel plants. EST sequences were submitted to the GenBank database (accession numbers BQ 103855 to BQ 106728).