Older adults use fewer muscles to overcome perturbations during a seated locomotor task

Speechreading and Aging

ABSTRACTMeaningful intergenerational interactions between older and younger adults are rare outside of family relationships. Interventions to increase positive intergenerational interactions are growing, but finding appropriate measures of attitudes toward both younger and older age groups is difficult. Many measures assessing attitudes toward older adults can remind participants of negative stereotypes of aging and are rarely used to assess attitudes toward younger adults. We adapted Pittinsky, Rosenthal, and Montoya’s allophilia measure to assess attitudes toward younger (18–25 years old) and older (over age 65) adults. In the first study, 94 traditional college age and 52 older adults rated older and younger adults. The allophilia measure distinguished between younger and older adults’ attitudes toward each age group. In the second study, we compared the age-related allophilia measures with seven traditional measures of attitudes toward older adults. Forty-seven traditional college age students completed measures. As predicted, correlations between allophilia toward older adults and the traditional semantic differential measures were weak (i.e., r = |0.15|or less), whereas correlations with general attitudes toward older adults were more moderate (r = 0.59 or less). Correlations between allophilia toward younger adults and the traditional measures were primarily non-significant as predicted. The allophilia measure differentiated between the five domains of positive attitudes toward younger and older adults and was not highly correlated with measures of more negative attitudes toward older adults. Results suggest that the allophilia measure can fill a need for a measure of positive attitudes toward older and younger adults.

Functional Assessment in Younger and Older Adults with Sickle Cell Disease

The ability to learn new movements and dynamics is important for maintaining independence with advancing age. Age-related sensorimotor changes and increased muscle coactivation likely alter the trial-and-error-based process of adapting to new movement demands (motor adaptation). Here, we asked, to what extent is motor adaptation to novel dynamics maintained in older adults (≥65 yr)? We hypothesized that older adults would adapt to the novel dynamics less well than young adults. Because older adults often use muscle coactivation, we expected older adults to use greater muscle coactivation during motor adaptation than young adults. Nevertheless, we predicted that older adults would reduce muscle activity and metabolic cost with motor adaptation, similar to young adults. Seated older (n = 11, 73.8 ± 5.6 yr) and young (n = 15, 23.8 ± 4.7 yr) adults made targeted reaching movements while grasping a robotic arm. We measured their metabolic rate continuously via expired gas analysis. A force field was used to add novel dynamics. Older adults had greater movement deviations and compensated for just 65% of the novel dynamics compared with 84% in young adults. As expected, older adults used greater muscle coactivation than young adults. Last, older adults reduced muscle activity with motor adaptation and had consistent reductions in metabolic cost later during motor adaptation, similar to young adults. These results suggest that despite increased muscle coactivation, older adults can adapt to the novel dynamics, albeit less accurately. These results also suggest that reductions in metabolic cost may be a fundamental feature of motor adaptation.

High Diagnostic Uncertainty and Inaccuracy in Adult Emergency Department Patients With Dyspnea: A National Database Analysis.

Effective processing of multisensory stimuli relies on both the peripheral sensory organs and central processing in subcortical and cortical structures. As we age, there are significant changes in all sensory systems and a variety of cognitive functions. Visual acuity tends to decrease and hearing thresholds generally increase (Kalina 1997; Liu and Yan 2007), whereas performance levels on tasks of motor speed, executive function, and memory typically decline (Rapp and Heindel 1994; Birren and Fisher 1995; Rhodes 2004). There are also widespread changes in the aging brain, including reductions in gray and white matter volume (Good et al. 2001; Salat et al. 2009), alterations in neurotransmitter systems (Muir 1997; Backman et al. 2006), regional hypoperfusion (Martin et al. 1991; Bertsch et al. 2009), and altered patterns of functional activity during cognitive tasks (Cabeza et al. 2004; Grady 2008). Given the extent of age-related alterations in sensation, perception, and cognition, as well as in the anatomy and physiology of the brain, it is not surprising that multisensory integration also changes with age.Several early studies provided mixed results on the differences between multisensory processing in older and younger adults (Stine et al. 1990; Helfer 1998; Strupp et al. 1999; Cienkowski and Carney 2002; Sommers et al. 2005). For example, Stine and colleagues (1990) reported that although younger adults’ memory for news events was better after audiovisual presentation than after auditory information alone, older adults did not show improvement during the multisensory conditions. In contrast, Cienkowski and Carney (2002) demonstrated that audiovisual integration on the McGurk illusion was similar for older and younger adults, and that in some conditions, older adults were even more likely to report the fusion of visual and auditory information than their young counterparts. Similarly, in a study examining the contribution of somatosensory input to participants’ perception of visuospatial orientation, Strupp et al. (1999) reported an age-related increase in the integration of somatosensory information into the multisensory representation of body orientation.Despite providing a good indication that multisensory processing is somehow altered in aging, the results of these studies are somewhat difficult to interpret due to their use of complex cognitive tasks and illusions, and to the variability in analysis methods. Several newer studies that have attempted to address these factors more clearly demonstrate that multisensory integration is enhanced in older adults (Laurienti et al. 2006; Peiffer et al. 2007; Diederich et al. 2008).On a two-choice audiovisual discrimination task, Laurienti and colleagues (2006) showed that response time (RT) benefits for multisensory versus unisensory targets were larger for older adults than for younger adults (Figure 20.1). That is, older adults’ responses during audiovisual conditions were speeded more than younger adults’, when compared with their respective responses during unisensory conditions. Multisensory gains in older adults remained significantly larger than those observed in younger adults, even after controlling for the presence of two targets in the multisensory condition (redundant target effect; Miller 1982, 1986; Laurienti et al. 2006).Using similar analysis methods, Peiffer et al. (2007) also reported increased multisensory gains in older adults. On a simple RT task, where average unisensory RTs were equivalent in younger and older adults, older adults actually responded faster than younger adults on multisensory trials because of their enhanced multisensory integration (Peiffer et al. 2007). Diederich and colleagues (2008) have also shown that older adults exhibit greater speeding of responses to multisensory targets than younger adults on a saccadic RT task. The analysis methods used in this experiment indicate a slowing of peripheral sensory processing, as well as a wider time window over which integration of auditory and visual stimuli can occur (Diederich et al. 2008).These experiments highlight several possible explanations that could help answer a critical question about multisensory processing in aging: Why do older adults exhibit greater integration of multisensory stimuli than younger adults? Potential sources of enhanced integration in older adults include age-related cognitive slowing not specific to multisensory processing, inverse effectiveness associated with sensory deficits, alterations in the temporal parameters of integration, and inefficient top–down modulation of sensory processing. In the following sections we will investigate each of these possible explanations in greater detail and offer some alternative hypotheses for the basis of enhanced multisensory integration in older adults.

The hyperemic response to passive leg movement (PLM) is largely (~80%) nitric oxide (NO) mediated in young adults, whereas both the overall response and NO contribution (~20%) are diminished in older adults. A transient hyperemic response remains in both groups after NO blockade, however, the mechanisms contributing to this remaining response are unknown. Vasodilatory substances including prostaglandins (PG) and endothelial derived hyperpolarizing factors (EDHF) are primary candidates contributing to PLM response. Moreover, these underlying mechanisms of the PLM response are likely influenced by exercise training in both young and older adults but this remains to be determined. Thus, we sought to determine if 1) PG and EDHF contribute to the hyperemic response in older adults, and 2) exercise training alters the mechanisms contributing to changes in PLM (i.e., NO, PG, or EDHF). The leg blood flow (LBF) response to PLM was measured by Doppler ultrasound in 9 young (25±4 yr) and 9 older (69±5 yr) adult males. PLM was performed with intra-arterial infusions of saline (control), NG-monomethyl-L-arginine (L-NMMA) to inhibit NOS and NO production, and a combination of L-NMMA, ketorolac tromethamine (KET) to inhibit cyclooxygenase and PG production, and fluconazole (FLUC) to inhibit cytochrome P-450 and EDHF (L-NMMA+KET+FLUC). This PLM and drug infusion protocol were repeated following 8 weeks of single leg knee-extension (KE) exercise training to determine if the vasodilatory mechanisms regulating PLM-induced hyperemia are altered by exercise training. The hyperemic response to PLM (total LBF area under the curve) was significantly attenuated from control with infusion of L-NMMA in young adults (-287±280 mL, p<0.05) but remained unchanged in the older (-55±86 mL, P=0.70). Combined infusion of L-NMMA+KET+FLUC yielded similar results such that PLM decreased to the same degree as L-NMMA in young (-276±108 mL, p<0.05) with no significant change in older adults (-116±81 mL, P=0.36). Following 8 weeks of single leg KE training, maximal power (KEmax) improved in both young (+33±13 W, p<0.05) and older adults (+16±8 W, p<0.05). Despite improvements in KEmax, the hyperemic response to PLM only increased in young adults by ~30% (454±194 v. 604±351 mL, p<0.05), while no improvement was observed in older adults (225±142 v. 236±89 mL, P=0.86). The contribution of NO to PLM did not change following exercise training in either young (-238±217 mL, P=0.14) or older (-62±82 mL, P=0.72) adults. Likewise, the contribution of PG and EDHF also did not change in both young (-306±222 mL, P=0.68) and older (-108±116 mL, P=0.77) adults. These findings indicate that PG and EDHF do not have an additive effect to NO on the hyperemic response to PLM in both young and older adults. Therefore, the remaining hyperemic response following combined NO, PG, and EDHF inhibition is likely driven by non-endothelial dependent mechanisms. Moreover, these data indicate that 8 weeks of KE specific exercise training significantly improves the hyperemic response to PLM in young but not older adults. Interestingly, the observed improvements to PLM were not directly mediated through the NO, PG, or EDHF pathways but by some other, currently unidentified, mechanism. National Institutes of Health R01HL142603 (to J.D. Trinity) This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Speech perception is critical to everyday life. Oftentimes noise can degrade a speech signal; however, because of the cues available to the listener, such as visual and semantic cues, noise rarely prevents conversations from continuing. The interaction of visual and semantic cues in aiding speech perception has been studied in young adults, but the extent to which these two cues interact for older adults has not been studied. To investigate the effect of visual and semantic cues on speech perception in older and younger adults, we recruited forty-five young adults (ages 18–35) and thirty-three older adults (ages 60–90) to participate in a speech perception task. Participants were presented with semantically meaningful and anomalous sentences in audio-only and audio-visual conditions. We hypothesized that young adults would outperform older adults across SNRs, modalities, and semantic contexts. In addition, we hypothesized that both young and older adults would receive a greater benefit from a semantically meaningful context in the audio-visual relative to audio-only modality. We predicted that young adults would receive greater visual benefit in semantically meaningful contexts relative to anomalous contexts. However, we predicted that older adults could receive a greater visual benefit in either semantically meaningful or anomalous contexts. Results suggested that in the most supportive context, that is, semantically meaningful sentences presented in the audiovisual modality, older adults performed similarly to young adults. In addition, both groups received the same amount of visual and meaningful benefit. Lastly, across groups, a semantically meaningful context provided more benefit in the audio-visual modality relative to the audio-only modality, and the presence of visual cues provided more benefit in semantically meaningful contexts relative to anomalous contexts. These results suggest that older adults can perceive speech as well as younger adults when both semantic and visual cues are available to the listener.

BackgroundCardiovascular diseases (CVDs) are a major cause of morbidity and mortality worldwide, with data showing an increasing trend. Previously uncommon, CVDs of lifestyle are now increasing in many Sub-Sahara African (SSA) countries including Tanzania. The study aimed at determining the spectrum and distribution of CVDs among young (< 45 years) and older (≥ 45 years) adults referred for echocardiography at Jakaya Kikwete Cardiac Institute (JKCI).MethodsHospital-based cross sectional study was conducted among adult patients referred for echocardiography at JKCI between July and December 2021. Patient’s socio-demographic and clinical characteristics were recorded. CVD diagnoses were made using established diagnostic criterias. Comparisons were done using chi-square test and student’s t-test. Multivariable logistic regression analysis was used to determine factors associated with abnormal echocardiography. A significance level was set at p-value < 0.05.ResultsIn total 1,050 patients (750 old and 300 young adults) were enrolled. The mean ± SD age was 62.2 ± 10.4 years and 33.5 ± 7.4 years for older and young adults respectively. Hypertension was the commonest indication for echocardiography both in the young (31%) and older (80%) adults. Majority of older adults were found to have abnormal echocardiography (90.7%), while only 44.7% of the young adults had abnormal echocardiography (p < 0.001). For the older adults, the commonest diagnoses were HHD (70.3%), IHD (9.7%), and non-ischemic cardiomyopathy (6.1%) while for young adults, HHD (16.7%), non-ischemic cardiomyopathy (8%), RHD (8%) and MVP (4.3%) were the commonest. The differences in the echocardiographic diagnoses between young and older adults were statistically significant, p < 0.001. Being an older adult, hypertensive, overweight/obese were independently associated with abnormal echocardiography (p < 0.01).ConclusionHypertensive heart disease is the most common diagnosis among adult patients referred for echocardiography at JKCI, both in young and older adults. Primary prevention, early detection and treatment of systemic hypertension should be reinforced in order to delay or prevent its complications.

The Role of Oxytocin in Older Adults’ Facial Emotion Recognition Difficulties

Introduction: The use of shared automated vehicles (SAVs) should lead to several societal and individual benefits, including reduced greenhouse gas emissions, reduced traffic, and improved mobility for persons who cannot safely drive themselves. We define SAVs as on-demand, fully automated vehicles in which passengers are paired with other riders traveling along a similar route. Previous research has shown that younger adults are more likely to report using conventional ridesharing services and are more accepting of new technologies including automated vehicles (AVs). However, older adults, particularly those who may be close to retiring from driving, stand to greatly benefit from SAV services. In order for SAVs to deliver on their aforementioned benefits, they must be viewed favorably and utilized. We sought to investigate how short educational and/or experiential videos might impact younger, middle-aged, and older adult respondents’ anticipated acceptance and attitudes toward SAVs. Knowing what types of introductory experiences improve different age groups’ perceptions of SAVs will be beneficial for tailoring campaigns aiming to promote SAV usage. Methods: We deployed an online survey using the platform Prolific for middle-aged and older respondents, and our departmental participant pool for younger adults, collecting 585 total responses that resulted in 448 valid responses. Respondents answered questions regarding their demographic attributes, their ridesharing history, preconceptions of technology, as well as their anticipated acceptance attitudes towards SAVs as measured by the dimensions of the Automated Vehicle User Perception Survey (AVUPS). After this, respondents were randomly assigned to an intervention condition where they either watched 1) an educational video about how SAVs work and their potential benefits, 2) an experiential video showing a AV navigating traffic, 3) both the experiential and educational videos, or 4) a control video explaining how ridesharing works. Anticipated acceptance attitudes towards SAVs were measured again after this intervention and difference scores calculated to investigate the effect of the intervention conditions. Prolific respondents were paid at a rate of $9.50/hour and younger adults received course credit. Results: Controlling for preconceptions of technology and ridesharing experience, a MANOVA was run on the difference scores of the dimensions of the AVUPS (intention to use, trust/reliability, perceived usefulness (PU), perceived ease of use (PEOU), safety, control/driving-efficacy, cost, authority, media, and social influence). Both older and middle-aged adults expressed significantly greater increases in PEOU and PU of SAVs than younger adults. We also observed an interaction between age and condition for both PU and PEOU. For PU, older adults’ difference scores were found to be significantly greater than younger adults’ for the control video condition. With PEOU, older adults’ difference scores were significantly greater than both younger adults’ for the control video condition, and middle-aged adults had greater difference scores for the educational-only video condition than younger or older adults. Discussion: The increases in PU observed for older adults in the control condition suggests that educating them on how to use currently available ridesharing services might transfer to and/or highlight the benefits that automated ridesharing might provide. The PEOU interactions also suggest that middle-aged adults might respond more positively than younger or older adults to an educational introduction to SAVs. Conclusion: The positive findings pertaining to PU and PEOU show that exposure to information related to SAVs has a positive impact on these attitudes. PU’s and PEOU’s positive relationship to behavioral intentions (BI) in the Technology Acceptance Model, coupled with the findings from this study, bode well for higher fidelity interventions seeking to inform and/or give individuals experience with SAVs. Providing information on how currently available ridesharing services work helped our older adult respondents recognize the potential usefulness of SAVs. Knowing that different age groups may respond better to educational versus experiential interventions, for example middle-aged adults in this study responding more positively to the educational video condition than younger or older adults, may be useful for targeted promotional campaigns.

Healthy ageing is characterised by deterioration of motor performance. In normal circumstances motor adaptation corrects for movements’ inaccuracies and as such, it is critical in maintaining optimal motor control. However, motor adaptation performance is also known to decline with age. Anodal transcranial direct current stimulation (TDCS) of the cerebellum and the primary motor cortex (M1) have been found to improve visuomotor adaptation in healthy young and older adults. However, no study has directly compared the effect of TDCS on motor adaptation between the two age populations. The aim of our study was to investigate whether the application of anodal TDCS over the lateral cerebellum and M1 affected motor adaptation in young and older adults similarly. Young and older participants performed a visuomotor rotation task and concurrently received TDCS over the left M1, the right cerebellum or received sham stimulation. Our results replicated the finding that older adults are impaired compared to the young adults in visuomotor adaptation. At the end of the adaptation session, older adults displayed a larger error (−17 deg) than the young adults (−10 deg). The stimulation of the lateral cerebellum did not change the adaptation in both age groups. In contrast, anodal TDCS over M1 improved initial adaptation in both age groups by around 30% compared to sham and this improvement lasted up to 40 min after the end of the stimulation. These results demonstrate that TDCS of M1 can enhance visuomotor adaptation, via mechanisms that remain available in the ageing population.

Objective:Epilepsy is the third most common neurological disorder among older adults, and as adults are living longer, the incidence of epilepsy is increasing (Kun Lee, 2019). The purpose of this study is to examine 1. differences in quality of life (QOL) between older and younger adults with medically intractable epilepsy and 2. the impact of seizure frequency, seizure duration, depression, sex, and marital status on QOL. Given differences in the prevalence rates of depression between men and women and importance of depression in QOL, we predicted that sex and marital status would moderate the effect of depression on total QOL (TQOL).Hypothesis I: Compared to younger adults, older adults with epilepsy will report lower TQOL scores and lower scores on subscales measuring energy/fatigue, cognition, and medication effects. Hypothesis II: Seizure variables and depression will significantly account for TQOL scores in both groups (younger and older) above demographic variables (sex, marital status, and education). Hypothesis III: Sex will moderate the effect of depression in both groups and marital status will moderate the effect of depression only in the older adults.Participants and Methods:Participants were 607 adults (&gt; 18 years old) who were prospective candidates for epilepsy surgery and underwent a comprehensive neuropsychological evaluation including QOL assessment using the Quality of Life in Epilepsy Scale-31 (QOLIE-31). Individuals were grouped by older (&gt; 50 years old; N = 122) and younger adults (&lt; 50 years old; N = 485). Hierarchical regression was used to examine the proposed associations.Results:Hypothesis I: In contrast to our hypothesis, a one-way ANOVA did not reveal significant differences between the older and younger groups on the QOL subscales, TQOL, or depression.Hypothesis II: For older adults, longer seizure duration was associated with better TQOL; bivariate correlations showed no evidence of statistical suppression. Higher depression scores were associated with worse TQOL. Overall, the model accounted for 39.6% of variance among older adults. For younger adults, only depression was a significant predictor of TQOL wherein higher depression scores were associated with worse TQOL. Overall, the model accounted for 36.1% of the variance among younger adults. Hypothesis III: There was no moderation between depression and marital status in older or younger adults (b = -.009, p &gt; .05). There was multicollinearity evidenced by VIF (variance inflation factor) greater than 10, so the associations between depression and sex could not be examined.Conclusions:Overall, there were no significant differences between QOL in younger versus older adults. Greater depression symptoms were associated with lower TQOL in both groups. Longer seizure duration was a significant predictor of better TQOL in older adults only, perhaps indicating better adjustment to having a seizure disorder with longer duration of epilepsy. Lastly, marital status did not moderate the effects of depression on TQOL and the moderating effects of sex on TQOL could not be assessed due to multicollinearity. Study limitations include dichotomizing the sample into these particular age groups and the heterogeneity of seizure types.

The sympathetic nervous system is an important regulator of coronary blood flow. The cold pressor test (CPT) is a powerful sympathoexcitatory stressor. We tested the hypotheses that: (1) CPT-induced sympathetic activation elicits coronary vasodilatation in young adults that is impaired with advancing age and (2) combined α- and β-adrenergic blockade diminishes/abolishes these age-related differences. Vascular responses of the left anterior descending artery to the CPT were determined by transthoracic Doppler echocardiography before (pre-blockade) and during (post-blockade) systemic co-administration of α- and β-adrenergic antagonists in young (n = 9; 26 ± 1 years old, mean ± SEM) and older healthy men (n = 9; 66 ± 2 years old). Coronary vascular resistance (CVR; mean arterial pressure/coronary blood velocity) was used as an index of vascular tone. CPT decreased CVR (i.e. coronary vasodilatation occurred) in young ( -33 ± 6%), but not older men ( -3 ± 4%; P < 0.05 vs. young) pre-blockade. Adrenergic blockade abolished CPT-induced coronary vasodilatation in young men ( -33 ± 6% vs. 0 ± 6%, pre-blockade vs. post-blockade, respectively; P < 0.05) such that responses post-blockade mirrored those of older men ( -3 ± 4% vs. 8 ± 9%; both P > 0.05 compared to young pre-blockade). Impaired CPT-induced coronary vasodilatation could not be explained by a reduced stimulus for vasodilatation as group and condition effects persisted when CVR responses were expressed relative to myocardial oxygen demand (rate-pressure product). These data indicate that the normal coronary vascular response to sympathetic activation in young men is pronounced vasodilatation and this effect is lost with age as the result of an adrenergic mechanism. These findings may help explain how acute sympathoexcitation may precipitate angina and coronary ischaemic events, particularly in older adults.

Comparative analysis of the safety and tolerability of eslicarbazepine acetate in older (≥60 years) and younger (18–59 years) adults