The Effects of Age and Hearing Loss on Dual-Task Balance and Listening

Association Between Hearing Loss, Asymmetric Hearing, and Postural Instability

OBJECTIVES

Recent studies have suggested that older adults with hearing loss (HL) are at a greater risk of postural instability than those with normal hearing. However, little is known regarding this association in middle-aged individuals. The relationships between HL laterality, asymmetric hearing, and posture control are similarly unclear. The purpose of this study was to investigate the effects of hearing status on postural control and to explore the dose-response relationship between the hearing threshold and postural instability risk in middle-aged adults.

DESIGN

This cross-sectional study included 1308 participants aged 40 to 69 years with complete audiometric and standing balance function data from the 2001-2004 National Health and Nutrition Examination Survey. Speech-frequency HL was defined as a pure-tone average at 0.5, 1, 2, and 4 kHz of >25 dB in the better-hearing ear; high-frequency HL was defined as a pure-tone average at 3, 4, and 6 kHz of >25 dB. Asymmetric hearing was defined as a difference in the pure-tone average >15 dB between ears. Postural instability was defined as participants ending the modified Romberg test in condition 4.

RESULTS

After adjustment for sociodemographic variables, lifestyle, and comorbidities, speech-frequency HL, except for unilateral HL, was associated with increased postural instability (mild HL: odds ratio [OR], 2.33; 95% confidence interval [CI], 1.25-4.35; moderate-to-severe HL: OR, 3.59; 95% CI, 1.61-8.03). Compared with individuals with normal bilateral hearing, participants with bilateral HL also showed a higher risk of postural instability (OR, 2.88; 95% CI, 1.61-5.14). The OR for postural instability among participants with asymmetric hearing compared with those with symmetric hearing was 2.75 (95% CI, 1.37-5.52). Furthermore, each 10 dB increase in the speech-frequency hearing threshold was associated with a 44% higher risk of postural instability.

CONCLUSIONS

Hearing loss is associated with poorer postural control. Individuals with asymmetric hearing have a higher postural instability risk compared with those with symmetric hearing. Further studies are needed to confirm these findings and the causality. Moreover, future studies are warranted to assess whether hearing aids are beneficial for the restoration of impaired balance functions.

Neuroanatomical correlates of distracted straight driving performance: a driving simulator MRI study across the lifespan

Background

Driving is the preferred mode of transportation for adults across the healthy age span. However, motor vehicle crashes are among the leading causes of injury and death, especially for older adults, and under distracted driving conditions. Understanding the neuroanatomical basis of driving may inform interventions that minimize crashes. This exploratory study examined the neuroanatomical correlates of undistracted and distracted simulated straight driving.

Methods

One-hundred-and-thirty-eight participants (40.6% female) aged 17-85 years old (mean and SD = 58.1 ± 19.9 years) performed a simulated driving task involving straight driving and turns at intersections in a city environment using a steering wheel and foot pedals. During some straight driving segments, participants responded to auditory questions to simulate distracted driving. Anatomical T1-weighted MRI was used to quantify grey matter volume and cortical thickness for five brain regions: the middle frontal gyrus (MFG), precentral gyrus (PG), superior temporal cortex (STC), posterior parietal cortex (PPC), and cerebellum. Partial correlations controlling for age and sex were used to explore relationships between neuroanatomical measures and straight driving behavior, including speed, acceleration, lane position, heading angle, and time speeding or off-center. Effects of interest were noted at an unadjusted p-value threshold of 0.05.

Results

Distracted driving was associated with changes in most measures of straight driving performance. Greater volume and cortical thickness in the PPC and cerebellum were associated with reduced variability in lane position and heading angle during distracted straight driving. Cortical thickness of the MFG, PG, PPC, and STC were associated with speed and acceleration, often in an age-dependent manner.

Conclusion

Posterior regions were correlated with lane maintenance whereas anterior and posterior regions were correlated with speed and acceleration, especially during distracted driving. The regions involved and their role in straight driving may change with age, particularly during distracted driving as observed in older adults. Further studies should investigate the relationship between distracted driving and the aging brain to inform driving interventions.

Dual- and Single-Task Training in Older Adults With Age-Related Hearing Loss: A Randomized Controlled Study

We aimed to investigate the effects of dual- and single-task training in older adults with age-related hearing loss. Intervention groups included single-, dual-task training, and control groups. The dual- and single-task trainings were held 2 days a week for 40 min for a total of 10 sessions for 5 weeks. We evaluated physical, cognitive, and auditory functions, quality-of-life, balance, concerns about falling, independence in activities of daily living, and dual-task performance. A total of 42 patients fully participated in this study. Statistically significant differences were observed in chair stand, chair sit-and-reach, global cognitive function, and delayed recall between the intervention groups and control group (p < .05). There was no statistically significant difference in quality-of-life, balance, falling concerns, independence in activities of daily living, and dual-task performance between all groups (p > .05). In conclusion, single- and dual-task training had a positive effect on physical and cognitive functioning in older adults with age-related hearing loss.

Hearing Aid Amplification Improves Postural Control for Older Adults With Hearing Loss When Other Sensory Cues Are Impoverished

Recent studies suggest that sound amplification via hearing aids can improve postural control in adults with hearing impairments. Unfortunately, only a few studies used well-defined posturography measures to assess balance in adults with hearing loss with and without their hearing aids. Of these, only two examined postural control specifically in the elderly with hearing loss. The present study examined the impact of hearing aid use on postural control during various sensory perturbations in older adults with age-related hearing loss. Thirty individuals with age-related hearing impairments and using hearing aids bilaterally were tested. Participants were asked to perform a modified clinical sensory integration in balance test on a force platform with and without hearing aids. The experiment was conducted in the presence of a broadband noise ranging from 0.1 to 4 kHz presented through a loudspeaker. As expected, hearing aid use had a beneficial impact on postural control, but only when visual and somatosensory inputs were both reduced. Data also suggest that hearing aid use decreases the dependence on somatosensory input for maintaining postural control. This finding can be of particular importance in older adults considering the reduction of tactile and proprioceptive sensitivity and acuity often associated with aging. These results provide an additional argument for encouraging early hearing aid fitting for people with hearing loss.

The Impact of Age-Related Hearing Loss on Working Memory among Older Individuals: An Event-Related Potential Study

Introduction

Age-related hearing loss (ARHL) may affect working memory (WM), which impacts problem-solving, decision-making, language comprehension, and learning. Limited research exists on how ARHL affects WM using N-back tasks, but studying this is crucial for understanding neural markers and associated cognitive processes. Our study explores the impact of ARHL on WM using behavioral and electrophysiological measures and how it correlates with speech-in-noise scores in older individuals with ARHL.

Method

The study involved two groups, each with 20 participants aged 60-80. Group 1 had individuals with mild to moderate sensorineural hearing loss, while Group 2 had age- and education-matched controls with normal or near-normal hearing. Participants underwent audiological assessments and completed cognitive tests, including simple reaction time and N-back tests. During the performance of cognitive tasks, a simultaneous electroencephalography was recorded. Data analysis included behavioral and event-related potentials, source estimation, and functional connectivity analysis.

Results

The study revealed significantly poor accuracy, longer reaction time, and smaller P300 amplitude among individuals with ARHL, even after controlling for general slowing. Individuals with ARHL experience compromised neural activity, particularly in the temporal and parietal regions, which are vital for cognition and WM. Furthermore, individuals with ARHL exhibited poor communication between the superior temporal gyrus and insulae regions among the brain regions mediating WM during the 1-back task. Also, the study found a strong correlation between hearing measures and WM outcomes.

Conclusion

The study findings suggest that individuals with ARHL have impaired WM compared to those with normal hearing. This indicates a potential link between ARHL and cognitive decline, which could significantly affect daily life and quality of life. The widely used WM test with simultaneous EEG recording and source estimation analysis would further validate the usefulness of the study in assessing WM in this population.

At-home computerized executive-function training to improve cognition and mobility in normal-hearing adults and older hearing aid users: a multi-centre, single-blinded randomized controlled trial

BACKGROUND

Hearing loss predicts cognitive decline and falls risk. It has been argued that degraded hearing makes listening effortful, causing competition for higher-level cognitive resources needed for secondary cognitive or motor tasks. Therefore, executive function training has the potential to improve cognitive performance, in turn improving mobility, especially when older adults with hearing loss are engaged in effortful listening. Moreover, research using mobile neuroimaging and ecologically valid measures of cognition and mobility in this population is limited. The objective of this research is to examine the effect of at-home cognitive training on dual-task performance using laboratory and simulated real-world conditions in normal-hearing adults and older hearing aid users. We hypothesize that executive function training will lead to greater improvements in cognitive-motor dual-task performance compared to a wait-list control group. We also hypothesize that executive function training will lead to the largest dual-task improvements in older hearing aid users, followed by normal-hearing older adults, and then middle-aged adults.

METHODS

A multi-site (Concordia University and KITE-Toronto Rehabilitation Institute, University Health Network) single-blinded randomized controlled trial will be conducted whereby participants are randomized to either 12 weeks of at-home computerized executive function training or a wait-list control. Participants will consist of normal-hearing middle-aged adults (45-60 years old) and older adults (65-80 years old), as well as older hearing aid users (65-80 years old, ≥ 6 months hearing aid experience). Separate samples will undergo the same training protocol and the same pre- and post-evaluations of cognition, hearing, and mobility across sites. The primary dual-task outcome measures will involve either static balance (KITE site) or treadmill walking (Concordia site) with a secondary auditory-cognitive task. Dual-task performance will be assessed in an immersive virtual reality environment in KITE's StreetLab and brain activity will be measured using functional near infrared spectroscopy at Concordia's PERFORM Centre.

DISCUSSION

This research will establish the efficacy of an at-home cognitive training program on complex auditory and motor functioning under laboratory and simulated real-world conditions. This will contribute to rehabilitation strategies in order to mitigate or prevent physical and cognitive decline in older adults with hearing loss.

TRIAL REGISTRATION

Identifier: NCT05418998. https://clinicaltrials.gov/ct2/show/NCT05418998.

Head movement and its relation to hearing

Head position at any point in time plays a fundamental role in shaping the auditory information that reaches a listener, information that continuously changes as the head moves and reorients to different listening situations. The connection between hearing science and the kinesthetics of head movement has gained interest due to technological advances that have increased the feasibility of providing behavioral and biological feedback to assistive listening devices that can interpret movement patterns that reflect listening intent. Increasing evidence also shows that the negative impact of hearing deficits on mobility, gait, and balance may be mitigated by prosthetic hearing device intervention. Better understanding of the relationships between head movement, full body kinetics, and hearing health, should lead to improved signal processing strategies across a range of assistive and augmented hearing devices. The purpose of this review is to introduce the wider hearing community to the kinesiology of head movement and to place it in the context of hearing and communication with the goal of expanding the field of ecologically-specific listener behavior.

Steroid hormones: risk and resilience in women's Alzheimer disease

More women have Alzheimer disease (AD) than men, but the reasons for this phenomenon are still unknown. Including women in clinical research and studying their biology is key to understand not just their increased risk but also their resilience against the disease. In this sense, women are more affected by AD than men, but their reserve or resilience mechanisms might delay symptom onset. The aim of this review was to explore what is known about mechanisms underlying women's risk and resilience in AD and identify emerging themes in this area that merit further research. We conducted a review of studies analyzing molecular mechanisms that may induce neuroplasticity in women, as well as cognitive and brain reserve. We also analyzed how the loss of steroid hormones in aging may be linked to AD. We included empirical studies with human and animal models, literature reviews as well as meta-analyses. Our search identified the importance of 17-b-estradiol (E2) as a mechanism driving cognitive and brain reserve in women. More broadly, our analysis revealed the following emerging perspectives: (1) the importance of steroid hormones and their effects on both neurons and glia for the study of risk and resilience in AD, (2) E2's crucial role in women's brain reserve, (3) women's verbal memory advantage as a cognitive reserve factor, and (4) E2's potential role in linguistic experiences such as multilingualism and hearing loss. Future directions for research include analyzing the reserve mechanisms of steroid hormones on neuronal and glial plasticity, as well as identifying the links between steroid hormone loss in aging and risk for AD.

Cognitive control in age-related hearing loss: A narrative review

Recent evidence suggests links between hearing loss and cognitive impairment in older adults with peripheral age-related hearing loss (ARHL). Earliest cognitive changes have been observed in cognitive control; however, a cohesive account of cognitive control alterations in older adults with peripheral ARHL is lacking. Cognitive control refers to cognitive processes that manage and regulate one's behavior to achieve desired goals. This review summarizes behavioral evidence on alterations in three cognitive control processes, including cognitive flexibility, inhibitory control, and working memory updating, in individuals with ARHL. Of the three processes, cognitive flexibility and working memory updating have been most extensively studied, with relatively fewer studies examining inhibitory control. Most consistent evidence is observed for long-term changes in cognitive flexibility, particularly in individuals with greater severity of ARHL. Equivocal evidence is seen for alterations in inhibitory control and working memory updating, with various factors contributing to inconsistencies across studies. Our review summarizes the emerging body of research on cognitive control in individuals with ARHL to guide future work in this area and considerations related to the management of cognitive issues in this population.

The Association between Hearing Impairment and Postural Stability in Older Adults: A Systematic Review and Meta-analysis

There is growing evidence linking hearing impairment to higher falls risk through alterations in postural stability, with studies showing mixed results. The primary aim of this systematic review and meta-analysis was to determine the association between hearing impairment and postural instability in older adults, including differences based on severity of hearing impairment. This review was pre-registered in PROSPERO and performed in accordance with PRISMA guidelines across six databases. Primary research on adults aged 60 years and older with hearing loss and an objective measure of postural stability or gait were eligible for inclusion. Methodological quality was assessed using the modified Newcastle-Ottawa Scale (NOS) adapted for cross-sectional studies. Data were analysed using meta-analyses and a narrative synthesis. Inclusion in the meta-analyses required clearly defined audiometrically-assessed hearing impairment, and two subgroups of participants: mild (25-40 dB HL) and moderate to-severe (>40 dB HL) hearing impairment. Twenty-five eligible studies (n = 27,847) were included in the narrative synthesis, with quality ratings ranging from unsatisfactory to very good on the modified NOS. Eight studies were included in the meta-analysis which showed individuals with moderate to-severe hearing impairment were significantly slower on the 5 x sit-to-stand test (mean difference[95%CI] = 0.50 s [0.04, 0.97], p = .03), had a slower gait speed (mean difference[95%CI] = -0.11 s [-0.16, -0.05], p < .001) and had lower total Short Physical Performance Battery scores (mean difference[95%CI] = -0.79[-1.17, -0.41], p < .001) than those with normal hearing. This review provides evidence there is an inverse association between increasing severity of hearing impairment and poorer postural stability across both the meta-analysis and narrative synthesis.

The significance of right ear auditory processing to balance

Although the association between balance and hearing thresholds at different frequencies in the right/left ear is crucial, it has received scant empirical attention. Balance is widely ignored when evaluating hearing in adults. This study examined the relative contribution of left versus right ear hearing at different frequencies to balance, and the mediating role of suprathreshold speech perception on age-balance associations. Pure tone hearing thresholds (500-4000 Hz), suprathreshold speech perception, balance, and risk of falling were evaluated in 295 adults. The results indicate that the right ear contributes more to balance than the left ear. This might imply dominance of the left hemisphere in processing hearing cues for balance. Frequencies within the speech range (500/1000/2000 Hz) were correlated with balance and mediated the interaction between age and balance. These results should be considered when tailoring hearing and balance rehabilitation programs.

Sex-Related Differences in the Associations Between Montreal Cognitive Assessment Scores and Pure-Tone Measures of Hearing

PURPOSE

Hearing loss (HL) is associated with cognitive performance in older adults, including performance on the Montreal Cognitive Assessment (MoCA), a brief cognitive screening test. Yet, despite well-established sex-related differences in both hearing and cognition, very few studies have tested whether there are sex-related differences in auditory-cognitive associations.

METHOD

In the current cross-sectional retrospective analysis, we examined sex-related differences in hearing and cognition in 193 healthy older adults (M = 69 years, 60% women). Hearing was measured using audiometry (pure-tone average [PTA] of thresholds at 500, 1000, 2000, and 4000 Hz in the worse ear). Cognition was assessed using the MoCA. Additionally, we calculated MoCA scores with hearing-dependent subtests excluded from scoring (MoCA-Modified).

RESULTS

Men and women did not differ in age, education, or history of depression. Women had better hearing than men. Women with normal hearing were more likely to pass the MoCA compared with their counterparts with HL. In contrast, the likelihood of passing the MoCA did not depend on hearing status in men. Linear regression analysis showed an interaction between sex and PTA in the worse ear. PTAs were significantly correlated with both MoCA and MoCA-Modified scores in women, whereas this was not observed in the men.

CONCLUSIONS

This study is one of the first to demonstrate significant sex-related differences in auditory-cognitive associations even when hearing-related cognitive test items are omitted. Potential mechanisms underlying these female-specific effects are discussed.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19233297.

The impact of divided attention on automatic postural responses: A systematic review and meta-analysis

Quick responses to a loss of balance or "automatic postural responses" (APRs) are critical for fall prevention. The addition of a distracting task- dual-tasking (DT), typically worsens performance on mobility tasks. However, the effect of DT on APRs is unclear. We conducted a systematic review and meta-analyses to examine the effects of DT on spatial, temporal, and neuromuscular components of APRs and the effect of DT on cognitive performance. A Meta-analysis of 19 cohorts (n = 329) showed significant worsening in spatial kinematic features of APRs under DT conditions (P = 0.01), and a meta-analysis of 9 cohorts (n = 123) demonstrated later muscle onset during DT (P = 0.003). No significant DT effect was observed for temporal kinematic outcomes in 18 cohorts (n = 328; P = 0.47). Finally, significant declines in cognitive performance were evident in 20 cohorts (n = 400; P = 0.002). These results indicate that, despite the somewhat reactive nature of APRs, the addition of a secondary task negatively impacts some aspects of the response. These findings underscore the importance of cortical structures in APR generation. Given the importance of APRs for falls, identifying aspects of APRs that are altered under DT may inform fall-prevention treatment approaches.

Dual-Task Performance in Hearing-Impaired Older Adults-Study Protocol for a Cross-Sectional Mobile Brain/Body Imaging Study

Background: Hearing impairments are associated with reduced walking performance under Dual-task (DT) conditions. Little is known about the neural representation of DT performance while walking in this target group compared to healthy controls or younger adults. Therefore, utilizing the Mobile Brain/Body Imaging approach (MoBI), we aim at gaining deeper insights into the brain dynamics underlying the interaction of cognitive and motor processes during different DT conditions (visual and auditory) controlling for age and the potential performance decrements of older adults with hearing impairments.

Methods: The cross-sectional study integrates a multifactorial mixed-measure design. Between-subject factors grouping the sample will be age (younger vs. older adults) and hearing impairment (mild vs. not hearing impaired). The within-subject factors will be the task complexity (single- vs. DT) and cognitive task modality (visual vs. auditory). Stimuli of the cognitive task will vary according to the stimulus modality (visual vs. auditory), presentation side (left vs. right), and presentation-response compatibility (ipsilateral vs. contralateral). Analyses of DT costs and underlying neuronal correlates focus either on gait or cognitive performance. Based on an a priori sample size calculation 96 (48 healthy and 48 mildly hearing impaired) community-dwelling older adults (50–70 years) and 48 younger adults (20–30 years) will be recruited. Gait parameters of speed and rhythm will be captured. EEG activity will be recorded using 64 active electrodes.

Discussion: The study evaluates cognitive-motor interference (CMI) in groups of young and older adults as well as older adults with hearing impairment. The underlying processes of the interaction between motor and cognitive tasks will be identified at a behavioral and neurophysiological level comparing an auditory or a visual secondary task. We assume that performance differences are linked to different cognitive-motor processes, i.e., stimulus input, resource allocation, and movement execution. Moreover, for the different DT conditions (auditory vs. visual) we assume performance decrements within the auditory condition, especially for older, hearing-impaired adults. Findings will provide evidence of general mechanisms of CMI (ST vs. DT walking) as well as task-specific effects in dual-task performance while over ground walking.

Assessing a Sensory-Motor-Cognition Triad in Amnestic Mild Cognitive Impairment With Dichotic Listening While Walking: A Dual-Task Paradigm

A contemporary topic in aging research relates to the significance of cognitive changes proper to mild cognitive impairment (MCI) to higher risk of falls and gait deteriorations. The present study addresses this question in the amnestic type of MCI (aMCI) by examining a triad of interrelated comorbidities occurring in the MCI condition: attentional impairments, hearing loss and gait disturbances. To this end, we applied a dichotic listening (DL) test during over-ground walking. DL assesses spontaneous and lateralized auditory attention in three conditions (i.e., free report or Non-forced (NF), Forced-Right (FR) ear and Forced-Left (FL) ear). Earlier reports suggest that this dual-task paradigm evoke asymmetric gait effects on healthy controls, which are moderated by degree of hearing loss. Therefore, the aim of the present study was to evaluate the effects of DL on bilateral (data from both limbs) and lateralized (each limb separately) gait outcomes in a group of forty-three aMCI participants (mean = 71.19) and fifty-two healthy older controls (mean = 70.90) by using hearing loss as a covariate in all analyses. Results showed the aMCI group presented overall compromised gait parameters, especially higher gait variability in all DL conditions during lateralized attentional control. These findings were observed bilaterally, and no lateralized effects on gait were observed. Only after controlling for hearing acuity, gait asymmetries on step length variability emerged almost exclusively in healthy controls. It was concluded that hearing loss in the aMCI group together with higher attentional impairments preclude aMCI individuals to properly execute DL and therefore, they do not display gait asymmetries. The present data demonstrate that varied demands on attentional control dependent on hearing acuity affects gait negatively in healthy older adults and aMCI individuals in very different ways. The appearance of asymmetric effects seems to be a perturbation related to normal aging, while the lack of asymmetries but exaggerated gait variability characterizes aMCI. The present findings show the intricate interplay of sensory, cognitive, and motor deteriorations in different group of older adults, which stresses the need of addressing co-occurring comorbidities behind gait perturbations in individuals prone to develop a dementia state.

Postural Control While Listening in Younger and Middle-Aged Adults

OBJECTIVES

The motivation for this research is to determine whether a listening-while-balancing task would be sensitive to quantifying listening effort in middle age. The premise behind this exploratory work is that a decrease in postural control would be demonstrated in challenging acoustic conditions, more so in middle-aged than in younger adults.

DESIGN

A dual-task paradigm was employed with speech understanding as one task and postural control as the other. For the speech perception task, participants listened to and repeated back sentences in the presence of other sentences or steady-state noise. Targets and maskers were presented in both spatially-coincident and spatially-separated conditions. The postural control task required participants to stand on a force platform either in normal stance (with feet approximately shoulder-width apart) or in tandem stance (with one foot behind the other). Participants also rated their subjective listening effort at the end of each block of trials.

RESULTS

Postural control was poorer for both groups of participants when the listening task was completed at a more adverse (vs. less adverse) signal-to-noise ratio. When participants were standing normally, postural control in dual-task conditions was negatively associated with degree of high-frequency hearing loss, with individuals who had higher pure-tone thresholds exhibiting poorer balance. Correlation analyses also indicated that reduced speech recognition ability was associated with poorer postural control in both single- and dual-task conditions. Middle-aged participants exhibited larger dual-task costs when the masker was speech, as compared to when it was noise. Individuals who reported expending greater effort on the listening task exhibited larger dual-task costs when in normal stance.

CONCLUSIONS

Listening under challenging acoustic conditions can have a negative impact on postural control, more so in middle-aged than in younger adults. One explanation for this finding is that the increased effort required to successfully listen in adverse environments leaves fewer resources for maintaining balance, particularly as people age. These results provide preliminary support for using this type of ecologically-valid dual-task paradigm to quantify the costs associated with understanding speech in adverse acoustic environments.

Fall-related Injuries Mediate the Relationship between Self-Reported Hearing Loss and Mortality in Middle-Aged and Older Adults

BACKGROUND

Hearing loss is associated with a greater risk of death in older adults. This relationship has been attributed to an increased risk of injury, particularly due to falling, in individuals with hearing loss. However, the link between hearing loss and mortality across the lifespan is less clear.

METHODS

We used structural equation modeling and mediation analysis to investigate the relationship between hearing loss, falling, injury, and mortality across the adult lifespan in public-use data from the National Health Interview Survey and the National Death Index. We examined 1) the association between self-reported hearing problems and later mortality, 2) the associations between self-reported hearing problems and the risk of injury and degree and type of injury, 3) the mediating role of falling and injury in the association between self-reported hearing problems and mortality, and 4) whether these relationships differ in young (18-39), middle-aged (40-59) and older (60+) age groups.

RESULTS

In all three age ranges, those reporting hearing problems were more likely to fall, were more likely to sustain an injury, and were more likely to sustain a serious injury, than those not reporting hearing problems. While there was no significant association between hearing loss and mortality in the youngest category, there was for middle-aged and older participants and for both fall-related injury was a significant mediator in this relationship.

CONCLUSIONS

Fall-related injury mediates the relationship between hearing loss and mortality for middle-aged as well as older adults, suggesting a need for further research into mechanisms and remediation.

Functional Gait Can Be Affected by Noise: Effects of Age and Cognitive Function: A Pilot Study

Background: The ageing process may degrade an individual's balance control, hearing capacity, and cognitive function. Older adults perform worse on simultaneously executed balance and secondary tasks (i.e., dual-task performance) than younger adults and may be more vulnerable to auditory distraction.

Aim: The purpose of this study was to determine the effect of passive listening on functional gait in healthy older vs. younger adults, and to investigate the effect of age, functional gait, hearing ability and cognitive functioning on dual-task performance.

Methods: Twenty young and 20 older healthy adults were recruited. Functional gait (Functional Gait Assessment in silent and noisy condition), hearing function (audiogram; Speech in Babble test), and cognitive ability (Cambridge Neuropsychological Test Automated Battery) were measured.

Results: Overall, a significant difference between functional gait performance in silent vs. noisy conditions was found (p = 0.022), with no significant difference in dual-task cost between the two groups (p = 0.11). Correlations were found between increasing age, worse functional gait performance, poorer hearing capacity and lower performance on cognitive function tasks. Interestingly, worse performance on attention tasks appeared to be associated with a worse functional gait performance in the noisy condition.

Conclusion: Passive listening to multi-talker babble noise can affect functional gait in both young and older adults. This effect could result from the cognitive load of the babble noise, due to the engagement of attention networks by the unattended speech.

Dual-task performance and vestibular functions in individuals with noise induced hearing loss

PURPOSE

The aim of this study was to evaluate the vestibular functions and dual-task performances of individuals with noise induced hearing loss.

MATERIALS AND METHODS

Fifty individuals with noise induced hearing loss and 25 healthy individuals were included in the study. Individuals with noise induced hearing loss were divided into 2 groups according to the pure tone average. Twenty-five patients with bilateral pure tone average between 20 dB HL and 40 dB HL were included in group I and 25 patients with bilateral pure tone average higher than 40 dB HL were included in group II. One-leg standing test, functional reach test, timed-up and go test, head impulse test, head shaking test, spontaneous nystagmus test and caloric test were carried out to evaluate the vestibular systems of all individuals. Visual analog scale was used to evaluate the imbalance intensity of individuals. In order to evaluate the dual-task performances of the individuals, individuals were given cognitive and motor tasks simultaneously with timed up and go test.

RESULTS

Individuals in group II had more abnormal caloric responses than the control group and individuals in group I. Also, individuals with higher hearing loss exhibited worse performance than other groups in eyes-closed one-leg standing test and dual-task situations.

CONCLUSION

Individuals with higher hearing loss (>40 dB) had more abnormal vestibular test results and worse dual-task performance than other groups. Vestibular evaluation and dual-task performance evaluation of factory workers with noise induced hearing loss can provide useful information to determine the risk of falling and fall prevention strategies in these individuals.

Early aging and postural control while listening and responding

It is not unusual for communication to take place while people are involved in another activity. This paper describes a study that measures the impact of listening while also completing an active postural control task. The focus was on whether the combination of listening and balancing was more detrimental to middle-aged adults than it was to younger adults as age-related changes in both hearing and postural control can occur within this age range. Speech understanding in the presence of noise and speech maskers was measured when participants (n = 15/group) were simply standing still, as well as when they were asked to complete a balancing-with-feedback postural control task, requiring different levels of effort. Performance on the postural control task also was measured in isolation. Results indicated that dual-task costs for postural control were larger when the masker was speech (vs noise) for the middle-aged group but not for the younger group. Dual-task costs in postural control increased with degree of high-frequency hearing loss even when age was controlled. Overall, results suggest that postural control in middle-aged adults can be compromised when individuals are communicating in challenging environments, perhaps reflecting an increased need for cognitive resources to successfully understand messages.

Age-related hearing loss associated with altered response efficiency and variability on a visual sustained attention task

This study investigated the association between age-related hearing loss (ARHL) and differences in response efficiency and variability on a sustained attention task. The study population comprised 32 participants in a hearing loss group (HLG) and 34 controls without hearing loss (CG). Mean reaction time (RT) and accuracy were recorded to assess response efficiency. RT variability was decomposed to examine temporal aspects of variability associated with neural arousal and top-down executive control of vigilant attention. The HLG had a significantly longer mean RT, possibly reflecting a strategic approach to maintain accuracy. The HLG also demonstrated altered variability (indicative of greater decline in neural arousal) but maintained executive control that was significantly predictive of poorer response efficiency. Adults with ARHL may rely on higher-order attention networks to compensate for decline in both peripheral sensory function and in subcortical arousal systems which mediate lower-order automatic neurocognitive processes.

The effect of simultaneously and sequentially delivered cognitive and aerobic training on mobility among older adults with hearing loss

BACKGROUND

Older adults exhibit declines in auditory and motor functioning, which are compensated for through the recruitment of cognitive resources. Cognitive or physical training alone has been shown to improve cognitive functioning and transfer to motor tasks, but results are mixed when these are combined in studies of healthy older adults, and few studies have included those with age-related hearing loss (ARHL), who are at a higher risk of falls.

RESEARCH QUESTION

To examine format effects in mixed training, we used a repeated measures intervention design to compare the efficacy of Simultaneous and Sequential multimodal training formats.

METHODS

42 older adults (M_age = 68.05, SD_age = 4.65, females = 26) with (ARHL) and without hearing loss (OAH) completed an intervention study consisting of 12 sessions of multimodal training (computerized cognitive dual-task and recumbent aerobic cycling). Participants were randomly assigned to either the Simultaneous (concurrent cognitive and aerobic) or Sequential training group (cognitive followed by aerobic) and completed assessments of single- and dual-task mobility concurrent with an auditory working memory task. Training gains were assessed with repeated measures ANOVAs using magnitude of improvement from pre- to post-training on primary outcome measures as the dependent variable.

RESULTS

Gains in auditory working memory were greater in the Sequential group than Simultaneous particularly among OAH. ARHL participants were unaffected by format. While all participants improved on a measure of chair rises, there was no benefit to standing balance. The results demonstrate an advantage to Sequential training, suggesting a benefit to focusing on each task in isolation.

SIGNIFICANCE

The gains noted in the ARHL indicate the potential benefit of incorporating cognitive remediation into traditional audiological rehabilitation. Moreover, it is important to consider the cost of dividing attention when combining training.

Cognitive Involvement in Balance, Gait and Dual-Tasking in Aging: A Focused Review From a Neuroscience of Aging Perspective

A substantial corpus of evidence suggests that the cognitive involvement in postural control and gait increases with aging. A large portion of such studies were based on dual-task experimental designs, which typically use the simultaneous performance of a motor task (e.g., static or dynamic balancing, walking) and a continuous cognitive task (e.g., mental arithmetic, tone detection). This focused review takes a cognitive neuroscience of aging perspective in interpreting cognitive motor dual-task findings. Specifically, we consider the importance of identifying the neural circuits that are engaged by the cognitive task in relation to those that are engaged during motor task performance. Following the principle of neural overlap, dual-task interference should be greatest when the cognitive and motor tasks engage the same neural circuits. Moreover, the literature on brain aging in general, and models of dedifferentiation and compensation, in particular, suggest that in cognitive motor dual-task performance, the cognitive task engages different neural substrates in young as compared to older adults. Also considered is the concept of multisensory aging, and the degree to which the age-related decline of other systems (e.g., vision, hearing) contribute to cognitive load. Finally, we discuss recent work on focused cognitive training, exercise and multimodal training of older adults and their effects on postural and gait outcomes. In keeping with the principle of neural overlap, the available cognitive training research suggests that targeting processes such as dividing attention and inhibition lead to improved balance and gait in older adults. However, more studies are needed that include functional neuroimaging during actual, upright performance of gait and balance tasks, in order to directly test the principle of neural overlap, and to better optimize the design of intervention studies to improve gait and posture.

Effects of Age on Dual-Task Walking While Listening

This study examined the effects of age on single- and dual-task listening and walking during virtual street crossing. Seventeen younger and 12 older adults participated. In each listening trial, three sentences were presented simultaneously from separate locations. Participants were instructed to report the target sentence. Predictability of the target sentence location was varied. Treadmill walking was measured using motion analysis. Measures included word recognition accuracy, head and trunk angles, and spatiotemporal gait parameters. Older adults exhibited a more upright head alignment and less variability in stride time during dual-tasking, particularly under less certain target sentence location conditions. Younger adults' walking was unaffected by dual-task demands. Together, the results indicate greater postural prioritization in older adults than young.