A study on how concurrent visual feedback affects motor learning of adjustability of grasping force in younger and older adults.

In this study, we investigated the differences of the effectiveness from concurrent visual feedback among younger and older adults in learning tasks that require adjustability of grasping force (AGF), as well as the functions related to AGF in each generation. The younger and older adult groups were evaluated for simple visual reaction time as visual-motor speed (VMS) and a 100 g AGF task that reflected the difference between desired performance and actual performance. The main learning task was then practiced using concurrent visual feedback and tested without feedback. The VMS of older adults was slower than that of the younger, and the error in the 100 g AGF task was larger in older adults than in the younger adults. Performance improved from pre-test to retention test in both groups, but the older adult group failed to reach the level of the younger adult group. The results of this study show that concurrent visual feedback is effective for learning the tasks that require AGF in both groups. Indicatively, improvement in performance during practice is insufficient in older people for whom there is a large difference between desired performance and actual performance, or whose VMS is slow.

Usefulness of an unstable board balance test to accurately identify community-dwelling elderly individuals with a history of falls.

OBJECTIVE: To determine the usefulness of an un-stable board balance test in identifying a fall history among high-functioning community-dwelling elderly individuals. DESIGN: Case-control study. SUBJECTS: Sixty-one community-dwelling elderly aged ≥ 65 years and having the capacity to walk independently without an assistive device. METHODS: Subjects completed 3 balance performance tests: the Unstable Board Balance Test, Functional Reach Test, and Timed Up and Go. For analysis, subjects were classified as fallers or non-fallers based on the history of falls over the previous year, and performance outcomes were compared between the 2 groups. Subjects classified as fallers were then matched 1:1 with non-fallers (for sex, age, body weight and height), and the optimal cut-off score and area under the receiver operating characteristic curve (AUC) for each test were calculated. RESULTS: Functional reach test and Timed Up and Go did not reliably discriminate between fallers and non-fallers. In contrast, the score on the unstable board balance test was significantly different between the 2 groups (p = 0.040). Among all 3 tests, AUC was largest for the unstable board balance test (0.78), with superior sensitivity (0.67) and specificity (0.87). CONCLUSION: For high-functioning elderly subjects, the unstable board balance test was useful in discriminating between fallers and non-fallers.

Dynamic balance assessment using an unstable board in community-dwelling elderly people.

[Purpose] A new method for measuring dynamic balance was developed. The aim of this study was to describe the use of a novel "unstable board" to evaluate the balance ability of community-dwelling elderly individuals. [Participants and Methods] The following balance outcomes were evaluated in 59 community-dwelling elderly people: anteroposterior and mediolateral stability indexes on the unstable board, Mini-Balance Evaluation Systems Test score, the Functional Reach Test score, Timed Up-and-Go time, and the Figure-8 Walk Test time. [Results] With respect to the relationship between the stability indexes and functional balance scales, the anteroposterior stability index significantly correlated with the anticipatory postural adjustment component (r=-0.422), stability in the gait component (r=-0.274), and total score of the Mini-Balance Evaluation Systems Test (r=-0.316); timed up-and-go time (r=0.320); and figure-8 walk test time (r=0.340). No correlation was found between the mediolateral stability index and the functional balance scale scores. [Conclusion] The anteroposterior stability index correlated with the declines in postural adjustments and performance in the dynamic balance assessments. Therefore, the anteroposterior stability index, evaluated on an unstable board, could provide an efficient tool for predicting changes in dynamic balance capacity, which could not be identified using the most commonly used balance assessment tools.

Assessing the adjustability of grasping force using the iWakka in elderly individuals.

[Purpose] To ensure that elderly individuals continue performing their activities of daily living, rehabilitation specialists have focused on several intervention programs, including programs that help maintain the functionality of digits. Grasping motion, including the ability to adjust grip, both spatially and temporally, is important for the elderly to continue independent living. The iWakka is a device used to measure the adjustability of grasping force and developed in Japan in 2012. This study aimed to evaluate the range of error of the iWakka, and verify its usefulness for evaluating adjustability of grasping force in elderly subjects. [Subjects and Methods] In 36 community-dwelling elderly subjects, over 65 years old, two readings of adjustability of grasping force, in the dominant and non-dominant hands were obtained using the iWakka, and a Bland-Altman analysis of the data was performed. [Results] The results demonstrated significant fixed bias in the dominant and non-dominant hands, but no significant proportional bias was observed. The limits of agreement were -2.8 to 4.4 g for dominant hand and -2.6 to 3.9 g for non-dominant hand. [Conclusion] Therefore, it is possible to measure the efficacy of interventions and detect declines in adjustability of grasping force using iWakka. Interventional programs can be designed for daily life based on the grasping force results shown by iWakka.