The Use of Vision in Manual Aiming by Young and Older Adults

1996 ◽  
Vol 4 (2) ◽  
pp. 165-178 ◽  
Author(s):  
James Lyons ◽  
Digby Elliott ◽  
Laurie R. Swanson ◽  
Romeo Chua

This study was designed to examine the influence of age and the availability of vision on the performance and kinematic characteristics of discrete aiming movements. Twelve young adults (19–25 years old) and 12 healthy older adults (62–82 years old) performed 130-mm aiming movements to targets with diameters of 5, 10, and 20 mm. On half the trial blocks, visual feedback about the aiming movement was eliminated upon movement initiation. Surprisingly, older adults were both as fast and as accurate as young adults regardless of the vision or target condition. While the velocity profiles of young and older adults were also similar, older adults exhibited a greater number of deviations in acceleration in both the vision and no-vision situations. Since these deviations are thought to reflect adjustments to the movement trajectory, older adults may rely more on visual and kinesthetic feedback for the control of goal-directed movement.

2019 ◽  
Vol 5 (s2) ◽  
Author(s):  
Daniel Müller-Feldmeth ◽  
Katharina Ahnefeld ◽  
Adriana Hanulíková

AbstractWe used self-paced reading to examine whether stereotypical associations of verbs with women or men as prototypical agents (e.g. the craftsman knits a sweater) are activated during sentence processing in dementia patients and healthy older adults. Effects of stereotypical knowledge on language processing have frequently been observed in young adults, but little is known about age-related changes in the activation and integration of stereotypical information. While syntactic processing may remain intact, semantic capacities are often affected in dementia. Since inferences based on gender stereotypes draw on social and world knowledge, access to stereotype information may also be affected in dementia patients. Results from dementia patients (n = 9, average age 86.6) and healthy older adults (n = 14, average age 79.5) showed slower reading times and less accuracy in comprehension scores for dementia patients compared to the control group. While activation of stereotypical associations of verbs was visible in both groups, they differed with respect to the time-course of processing. The effect of stereotypes on comprehension accuracy was visible for healthy adults only. The evidence from reading times suggests that older adults with and without dementia engage stereotypical inferences during reading, which is in line with research on young adults.


2019 ◽  
Vol 121 (2) ◽  
pp. 690-700 ◽  
Author(s):  
Chesney E. Craig ◽  
Michail Doumas

We investigated whether postural aftereffects witnessed during transitions from a moving to a stable support are accompanied by a delayed perception of platform stabilization in older adults, in two experiments. In experiment 1, postural sway and muscle cocontraction were assessed in 11 healthy young, 11 healthy older, and 11 fall-prone older adults during blindfolded stance on a fixed platform, followed by a sway-referenced platform and then by a fixed platform again. The sway-referenced platform was more compliant for young adults, to induce similar levels of postural sway in both age groups. Participants were asked to press a button whenever they perceived that the platform had stopped moving. Both older groups showed significantly larger and longer postural sway aftereffects during platform stabilization compared with young adults, which were pronounced in fall-prone older adults. In both older groups elevated muscle cocontraction aftereffect was also witnessed. Importantly, these aftereffects were accompanied by an illusory perception of prolonged platform movement. After this, experiment 2 examined whether this illusory perception was a robust age effect or an experimental confound due to greater surface compliance in young adults, which could create a larger perceptual discrepancy between moving and stable conditions. Despite exposure to the same surface compliance levels during sway-reference, the perceptual illusion was maintained in experiment 2 in a new group of 14 healthy older adults compared with 11 young adults. In both studies, older adults took five times longer than young adults to perceive platform stabilization. This supports that sensory reweighting is inefficient in older adults. NEW & NOTEWORTHY This is the first paper to show that postural sway aftereffects witnessed in older adults after platform stabilization may be due to a perceptual illusion of platform movement. Surprisingly, in both experiments presented it took older adults five times longer than young adults to perceive platform stabilization. This supports a hypothesis of less efficient sensory reintegration in this age group, which may delay the formation of an accurate postural percept.


2021 ◽  
pp. 1-13
Author(s):  
Matthew N. Petrucci ◽  
Sommer Amundsen Huffmaster ◽  
Jae Woo Chung ◽  
Elizabeth T. Hsiao-Wecksler ◽  
Colum D. MacKinnon

Background: An external cue can markedly improve gait initiation in people with Parkinson’s disease (PD) and is often used to overcome freezing of gait (FOG). It is unknown if the effects of external cueing are comparable if the imperative stimulus is triggered by the person receiving the cue (self-triggered) or an external source. Objective: Two experiments were conducted to compare the effects of self- versus externally triggered cueing on anticipatory postural adjustments (APAs) during gait initiation in people with PD. Methods: In experiment 1, 10 individuals with PD and FOG initiated gait without a cue or in response to a stimulus triggered by the experimenter or by the participant. Experiment 2 compared self- versus externally triggered cueing across three groups: healthy young adults (n = 16), healthy older adults (n = 11), and a group with PD (n = 10). Results: Experiment 1: Externally triggered cues significantly increased APA magnitudes compared to uncued stepping, but not when the same cue was self-triggered. Experiment 2: APAs were not significantly improved with a self-triggered cue compared to un-cued stepping in both the PD and healthy older adult groups, but the young adults showed a significant facilitation of APA magnitude. Conclusion: The effectiveness of an external cue on gait initiation in people with PD and older adults is critically dependent upon whether the source of the trigger is endogenous (self-produced) or exogenous (externally generated). These results may explain why cueing interventions that rely upon self-triggering of the stimulus are often ineffective in people with PD.


Author(s):  
Ernest K. Ofori ◽  
Savitha Subramaniam ◽  
Shuaijie Wang ◽  
Tanvi Bhatt

Background: Recent studies demonstrate improvements in both postural stability and mobility among aging populations and those with stroke who are exposed to dance-based exergaming (DBExG). However, age-related deficits and aging with cortical pathology may lead to distinct movement adaptation patterns during DBExG, which could impact therapeutic outcomes.Aim: The aim of this study was to examine the movement kinematics (postural stability and mobility) of healthy older adults, older adults with stroke, and young adults for different paces of dance during DBExG. Method: The study included 33 particpants (11 participant from each group of healthy older adults, older adults with chronic stroke, and healthy young adults) who performed the DBExG using slow- (SP), medium- (MP), and fast-paced (FP) songs with movements in the anteroposterior (AP) and mediolateral (ML) directions. Center of mass (CoM) sway area, excursion (Ex), and peaks as well as hip, knee, and ankle joint excursions were computed. Results: Results of the study revealed that CoM sway areas and Exs were greater for healthy young adults than for older adults with stroke for the SP dance (p < 0.05) and that there were significantly more AP CoM peaks for young adults than for healthy older adults and those with stroke for the FP dance (p < 0.05). Young adults also exhibited greater hip and ankle Exs than older adults with stroke (p < 0.05) for all song paces. Similarly, knee and ankle Exs were greater for healthy older adults than for older adults with stroke for all song paces (p < 0.05). Conclusion: The quantitative evaluation and comparison of the movement patterns presented for the three groups could provide a foundation for both assessing and designing therapeutic DBExG protocols for these populations.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 704-704
Author(s):  
Alan Kersten ◽  
Julie Earles ◽  
Jennifer Brymer

Abstract This research tested whether performing an action themselves leads young and older adults to have difficulty remembering which of a number of other people had performed that same action. It also tested whether observing another person perform an action leads to false memory for self-performance of that action. Young adults and healthy older adults 62 to 88 years of age viewed videos of actors performing actions. After viewing some of the actions, participants were instructed to perform those same actions themselves. Participants were tested one week later on their memory for their own actions and for the actions of the actors in the videos. Older adults were more strongly influenced by self-performance than were young adults when asked whether the actor in a test item had performed the same action previously. Young adults performed better than older adults at discriminating the correct and incorrect actors in the videos, although both groups showed reduced discrimination for actions that they had also performed themselves. The two groups were equally likely to falsely remember having performed an action that had only appeared in the videos, but young adults were better able than older adults to correctly identify the actions that they had in fact performed. Older adults thus have greater difficulty than young adults at distinguishing self-performed actions from actions performed by other people. This suggests the existence of common representations for the actions of oneself and others that must be bound to identity information to specify the correct source of the actions.


2010 ◽  
Vol 16 (3) ◽  
pp. 556-565 ◽  
Author(s):  
LANA J. OZEN ◽  
ERIN I. SKINNER ◽  
MYRA A. FERNANDES

AbstractThe most common cognitive complaint reported by healthy older adults and young adults with traumatic brain injury (TBI) is memory difficulties. We investigated the effects of normal aging and the long-term effects of TBI in young adults on the susceptibility to incorrectly endorse distracter information on a memory test. Prior to a study phase, participants viewed a “pre-exposure” list containing distracter words, presented once or three times, and half of the target study words. Subsequently, during the study phase, all target words were presented such that, across lists, study words were viewed either once or three times. On the recognition test, TBI and older adult participants were more likely to falsely endorse “pre-exposed” distracter words viewed three times as being from the target study list, compared to non-head-injured young controls. Normal aging and head injury in young may similarly compromise one’s ability to reject highly familiar, but distracting, information during recognition. Older adult and TBI participants were also slower to complete the Trail Making task and had poorer output on a Digit Span task, suggesting these two populations share a deficit in executive function and working memory. Similar changes in frontal lobe function may underlie these shared cognitive deficits. (JINS, 2010,16, 556–565.)


1995 ◽  
Vol 12 (3) ◽  
pp. 239-249 ◽  
Author(s):  
David A. Le Clair ◽  
Digby Elliott

This study examined the extent to which individuals with Down syndrome benefit from visual and verbal advance information about a manual aiming movement. Adults with Down syndrome as well as control subjects with and without mental handicaps performed 10.5-cm manual aiming movements with their preferred hand. On each trial subjects were cued about the specific movement either visually or verbally. On different trial blocks, the cue provided either 50% or 80% certainty. Nonhandicapped control subjects initiated and completed their manual aiming movements more quickly than subjects with mental handicaps. As well, individuals with Down syndrome were found to be slower and more variable in reaction time than participants in the other mentally handicapped group when valid information was provided verbally but not when the cue was provided visually. These results are consistent with the proposal that atypical hemispheric lateralization for speech perception associated with Down syndrome disrupts communication between functional systems responsible for processing of verbal language and organizing movement (Elliott & Weeks, 1993b).


1998 ◽  
Vol 41 (1) ◽  
pp. 41-50 ◽  
Author(s):  
Amy B. Wohlert ◽  
Anne Smith

Although the intelligibility of healthy older adults normally seems unimpaired, age-related changes occur in sensorimotor components of the speech system and in such global parameters as speech rate. In order to clarify the effect of these changes on the variability of speech movements, we examined oral peripheral abilities, speech rate, and speech kinematics in a group of 10 adults age 76–83, compared to a group of 10 young adults. Participants repeated a short phrase 15 times at habitual, fast, and slow rates. The resulting lip displacement signals were time- and amplitude-normalized, and successive standard deviations along the movement waveforms were summed to produce a spatiotemporal index (STI) representing individual variability in movement pattern. Participants tended to show greatest variability at slow rate, less variability at fast rate, and least variability at habitual rate. For the older adults, STI at habitual rate was significantly higher (more variable) and speech durations were longer than those of young adults. Perioral strength and tactile acuity were poorer in these older adults than in young adults. We conclude that as sensorimotor abilities change in old age, speakers are less consistent in the spatiotemporal organization of speech movements, reflecting decreased stability of speech motor control.


2009 ◽  
Vol 57 (7) ◽  
pp. 1245-1251 ◽  
Author(s):  
Jeanne F. Duffy ◽  
Hannah J. Willson ◽  
Wei Wang ◽  
Charles A. Czeisler

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