Age and Not the Preferred Limb Influences the Kinematic Structure of Pointing Movements

Bimanual motor impairments in older adults: an updated systematic review and meta-analysis

This updated systematic review and meta-analysis further examined potential effects of aging on bimanual movements. Forty-seven qualified studies that compared bimanual motor performances between elderly and younger adults were included in this meta-analysis. Moderator variable analyses additionally determined whether altered bimanual motor performances in older adults were different based on the task types (i.e., symmetry vs. asymmetry vs. complex) or outcome measures (i.e., accuracy vs. variability vs. movement time). The random effects model meta-analysis on 80 comparisons from 47 included studies revealed significant negative overall effects indicating more bimanual movement impairments in the elderly adults than younger adults. Moderator variable analyses found that older adults showed more deficits in asymmetrical bimanual movement tasks than symmetrical and complex tasks, and the bimanual movement impairments in the elderly adults included less accurate, more variable, and greater movement execution time than younger adults. These findings suggest that rehabilitation programs for improving motor actions in older adults are necessary to focus on functional recovery of interlimb motor control including advanced motor performances as well coordination.

Compensation in Time and Space: Prominence Marking in Aging and Disease

This study aims to explore the effects of healthy aging and Parkinson’s disease on speech motor performance. One area of speech production which requires fine speech motor control is prominence marking. Therefore, strategies of prominence marking of three speaker groups with four speakers each were investigated: younger speakers, older speakers, and speakers with Parkinson’s disease (PD). Acoustic and articulatory data were collected. Speech data were analyzed focusing on prominence-related adjustments of vowel production and tongue body movements in the temporal and spatial domain. Longer durations, varying initiation of the tongue movements and smaller vowel sizes in older speakers and in speakers with PD were found compared to younger speakers. The data indicate further that all speaker groups mark prominence by changing relevant parameters in the vowel articulation; however, strategies seem to differ between the groups: (i) in the temporal domain, articulatory movement durations increase with age and are further prolonged in speakers with PD; (ii) in the spatial domain, the articulation space is resized by the older speakers in a non-symmetrical way, while no systematic vocalic modulations were found for speakers with PD. To conclude, the speech system seems to be affected by age and disease, but speakers develop compensatory strategies to counteract influences in the spatial domain.