Aging effects on contrast sensitivity in visual pathways: A pilot study on flicker adaptation

Contrast sensitivity is reduced in older adults and is often measured at an overall perceptual level. Recent human psychophysical studies have provided paradigms to measure contrast sensitivity independently in the magnocellular (MC) and parvocellular (PC) visual pathways and have reported desensitization in the MC pathway after flicker adaptation. The current study investigates the influence of aging on contrast sensitivity and on the desensitization effect in the two visual pathways. The steady- and pulsed-pedestal paradigms were used to measure contrast sensitivity under two adaptation conditions in 45 observers. In the non-flicker adaptation condition, observers adapted to a pedestal array of four 1°×1° squares presented with a steady luminance; in the flicker adaptation condition, observers adapted to a square-wave modulated luminance flicker of 7.5 Hz and 50% contrast. Results showed significant age-related contrast sensitivity reductions in the MC and PC pathways, with a significantly larger decrease of contrast sensitivity for individuals older than 50 years of age in the MC pathway but not in the PC pathway. These results are consistent with the hypothesis that sensitivity reduction observed at the overall perceptual level likely comes from both the MC and PC visual pathways, with a more dramatic reduction resulting from the MC pathway for adults >50 years of age. In addition, a similar desensitization effect from flicker adaptation was observed in the MC pathway for all ages, which suggests that aging may not affect the process of visual adaptation to rapid luminance flicker.

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Strategies and cognitive reserve to preserve lexical production in aging

GeroScience ◽

10.1007/s11357-021-00367-5 ◽

2021 ◽

Author(s):

Monica Baciu ◽

Sonja Banjac ◽

Elise Roger ◽

Célise Haldin ◽

Marcela Perrone-Bertolotti ◽

...

Keyword(s):

Older Adults ◽

Cognitive Aging ◽

Individual Variability ◽

Future Research ◽

Aging Effects ◽

Main Hypothesis ◽

Compensatory Strategies ◽

Age Related ◽

Complementary Domain

AbstractIn the absence of any neuropsychiatric condition, older adults may show declining performance in several cognitive processes and among them, in retrieving and producing words, reflected in slower responses and even reduced accuracy compared to younger adults. To overcome this difficulty, healthy older adults implement compensatory strategies, which are the focus of this paper. We provide a review of mainstream findings on deficient mechanisms and possible neurocognitive strategies used by older adults to overcome the deleterious effects of age on lexical production. Moreover, we present findings on genetic and lifestyle factors that might either be protective or risk factors of cognitive impairment in advanced age. We propose that “aging-modulating factors” (AMF) can be modified, offering prevention opportunities against aging effects. Based on our review and this proposition, we introduce an integrative neurocognitive model of mechanisms and compensatory strategies for lexical production in older adults (entitled Lexical Access and Retrieval in Aging, LARA). The main hypothesis defended in LARA is that cognitive aging evolves heterogeneously and involves complementary domain-general and domain-specific mechanisms, with substantial inter-individual variability, reflected at behavioral, cognitive, and brain levels. Furthermore, we argue that the ability to compensate for the effect of cognitive aging depends on the amount of reserve specific to each individual which is, in turn, modulated by the AMF. Our conclusion is that a variety of mechanisms and compensatory strategies coexist in the same individual to oppose the effect of age. The role of reserve is pivotal for a successful coping with age-related changes and future research should continue to explore the modulating role of AMF.

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Aging effects on neural processing of rhythm and meter

10.31234/osf.io/qku6e ◽

2022 ◽

Author(s):

Sarah Anne Sauvé ◽

Emily Bolt ◽

Sylvie Nozaradan ◽

Benjamin Zendel

Keyword(s):

Older Adults ◽

Hearing Loss ◽

Brain Activity ◽

Aging Effects ◽

Brain Response ◽

Younger Adults ◽

Musical Rhythm ◽

Low Level ◽

Age Related ◽

Rhythm And Meter

When listening to musical rhythm, humans can perceive and move to beat-like metrical pulses. Recently, it has been hypothesized that meter perception is related to brain activity responding to the acoustic fluctuation of the rhythmic input, with selective enhancement of the brain response elicited at meter-related frequencies. In the current study, the electroencephalography (EEG) was recorded while younger (<35) and older (>60) adults listened to rhythmic patterns presented at two different tempi while intermittently performing a tapping task. Despite significant hearing loss compared to younger adults, older adults showed preserved brain activity to the rhythms. However, age effects were observed in the distribution of amplitude across frequencies. Specifically, in contrast with younger adults, older adults showed relatively larger amplitude at the frequency corresponding to the rate of individual events making up the rhythms as compared to lower meter-related frequencies. This difference is compatible with larger N1-P2 potentials as generally observed in older adults in response to acoustic onsets, irrespective of meter perception. These larger low-level responses to sounds have been linked to processes by which age-related hearing loss would be compensated by cortical sensory mechanisms. Importantly, this low-level effect would be associated here with relatively reduced neural activity at lower frequencies corresponding to higher-level metrical grouping of the acoustic events, as compared to younger adults.

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Age-related decline in motion contrast sensitivity due to lower absorption rate of cones and calculation efficiency

Scientific Reports ◽

10.1038/s41598-020-73322-7 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Asma Braham chaouche ◽

Daphné Silvestre ◽

Arthur Trognon ◽

Angelo Arleo ◽

Rémy Allard

Keyword(s):

Older Adults ◽

Contrast Sensitivity ◽

Modulation Transfer Function ◽

Absorption Rate ◽

Healthy Aging ◽

Internal Noise ◽

Modulation Transfer ◽

Temporal Modulation ◽

Age Related ◽

Motion Contrast

Abstract Motion perception is affected by healthy aging, which impairs the ability of older adults to perform some daily activities such as driving. The current study investigated the underlying causes of age-related motion contrast sensitivity losses by using an equivalent noise paradigm to decompose motion contrast sensitivity into calculation efficiency, the temporal modulation transfer function (i.e., temporal blur) and 3 sources of internal noise: stochastic absorption of photons by photoreceptors (i.e., photon noise), neural noise occurring at the retinal level (i.e., early noise) and at the cortical level (i.e., late noise). These sources of internal noise can be disentangled because there impacts on motion contrast sensitivity vary differently as a function of luminance intensity. The impact of healthy aging on these factors was evaluated by measuring motion contrast sensitivity of young and older healthy adults at different luminance intensities, temporal frequencies and with/without external noise. The older adults were found to have higher photon noise, which suggests a lower photon absorption rate of cones. When roughly equating the amount of photons being absorbed by the photoreceptors, older adults had lower calculation efficiencies, but no significant aging effect was found on temporal modulation transfer function, early noise and late noise.

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Computer Accessibility Issues for Older Adults with Disabilities: A Pilot Study

OTJR Occupation Participation and Health ◽

10.1177/153944920502500203 ◽

2005 ◽

Vol 25 (2) ◽

pp. 55-65 ◽

Cited By ~ 2

Author(s):

Tanya D. Marchant ◽

Tina Marie Tiernan ◽

William C. Mann

Keyword(s):

Older Adults ◽

Pilot Study ◽

Computer Use ◽

Adults With Disabilities ◽

Age Related ◽

Workstation Design ◽

Accessibility Issues ◽

Performance Satisfaction ◽

Perception Of Performance ◽

Increased Susceptibility

The number of adults older than 65 years is expected to increase dramatically during the next 30 years. Older adults have been described as one of the fastest growing groups of computer users, and have been shown to uniquely benefit from computer use. Given their increased susceptibility toward disabling conditions and age-related decline, older adults often face challenges regarding computer use and accessibility. The purpose of this pilot study was to explore computer use and accessibility issues of older adults with disabilities, focusing on relationships between workstation, performance, satisfaction, and self-reported pain. A sample of 32 older adults with disabilities who owned and used a personal computer were interviewed in their homes and observed during performance of a familiar computer task. Their computer workstations were also assessed for adherence to ergonomic principles. Satisfaction with their computer ability was found to be positively correlated with workstation design, their perception of the importance of a computer, duration of use per week, and participants' perception of performance. No significant differences were found between older adults who did and did not report pain associated with computer use. Results suggest that older adults with disabilities are using computers for many tasks, consider their computers important, perceive their performance as relatively good, and are generally satisfied with their ability to use their computer. There is a need for further research examining the correlates of older adults' satisfaction with their ability to use their computer.

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Effect of informational content of noise on speech representation in the aging midbrain and cortex

Journal of Neurophysiology ◽

10.1152/jn.00373.2016 ◽

2016 ◽

Vol 116 (5) ◽

pp. 2356-2367 ◽

Cited By ~ 47

Author(s):

Alessandro Presacco ◽

Jonathan Z. Simon ◽

Samira Anderson

Keyword(s):

Older Adults ◽

Speech Signal ◽

Informational Content ◽

Cognitive Resources ◽

Noisy Environments ◽

Aging Effects ◽

Contextual Cues ◽

Age Related ◽

Behavioral Studies ◽

Cortical Responses

The ability to understand speech is significantly degraded by aging, particularly in noisy environments. One way that older adults cope with this hearing difficulty is through the use of contextual cues. Several behavioral studies have shown that older adults are better at following a conversation when the target speech signal has high contextual content or when the background distractor is not meaningful. Specifically, older adults gain significant benefit in focusing on and understanding speech if the background is spoken by a talker in a language that is not comprehensible to them (i.e., a foreign language). To understand better the neural mechanisms underlying this benefit in older adults, we investigated aging effects on midbrain and cortical encoding of speech when in the presence of a single competing talker speaking in a language that is meaningful or meaningless to the listener (i.e., English vs. Dutch). Our results suggest that neural processing is strongly affected by the informational content of noise. Specifically, older listeners' cortical responses to the attended speech signal are less deteriorated when the competing speech signal is an incomprehensible language rather than when it is their native language. Conversely, temporal processing in the midbrain is affected by different backgrounds only during rapid changes in speech and only in younger listeners. Additionally, we found that cognitive decline is associated with an increase in cortical envelope tracking, suggesting an age-related over (or inefficient) use of cognitive resources that may explain their difficulty in processing speech targets while trying to ignore interfering noise.

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Age-Related Differences in Sequential Modulations of Poorer-Strategy Effects

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000244 ◽

2014 ◽

Vol 61 (4) ◽

pp. 253-262 ◽

Cited By ~ 21

Author(s):

Patrick Lemaire ◽

Thomas Hinault

Keyword(s):

Older Adults ◽

Executive Control ◽

Error Rates ◽

Control Mechanisms ◽

Strategy Execution ◽

Aging Effects ◽

Estimation Task ◽

Younger Adults ◽

Computational Estimation ◽

Age Related

To determine how younger and older adults modulate execution of strategies across successive trials, we asked participants to accomplish a computational estimation task (i.e., provide approximate products to two-digit multiplication problems like 38 × 74). For each problem, they were cued to execute a better versus a poorer strategy. Their performance revealed sequential modulations of poorer-strategy effects (i.e., longer solution times and larger error rates when asked to execute a poorer than a better strategy). That is, poorer-strategy effects were smaller on current problems after using a poorer strategy on preceding problems than after using a better strategy. Moreover, sequential modulations of these poorer-strategy effects were smaller in older than in younger adults, especially older adults with low-cognitive control skills (as measured by conflict adaptation effects in the Simon task). Our findings suggest that these sequential modulations may result from executive control mechanisms, the efficiency of which is known to decrease in older adults. These findings have important implications regarding mechanisms underlying strategy execution and aging effects on strategic variations.

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Aging Effects on the Neuroplastic Attributes of Multisensory Cortical Networks as Triggered by a Computerized Music Reading Training Intervention

Cerebral Cortex ◽

10.1093/cercor/bhaa213 ◽

2020 ◽

Vol 31 (1) ◽

pp. 123-137

Author(s):

Evangelos Paraskevopoulos ◽

Nikolas Chalas ◽

Alexandros Karagiorgis ◽

Maria Karagianni ◽

Charis Styliadis ◽

...

Keyword(s):

Older Adults ◽

Multisensory Integration ◽

Inferior Frontal Gyrus ◽

Music Reading ◽

Aging Effects ◽

Younger Adults ◽

Brain Functioning ◽

Age Related ◽

Multisensory Learning ◽

Computer Based

Abstract The constant increase in the graying population is the result of a great expansion of life expectancy. A smaller expansion of healthy cognitive and brain functioning diminishes the gains achieved by longevity. Music training, as a special case of multisensory learning, may induce restorative neuroplasticity in older ages. The current study aimed to explore aging effects on the cortical network supporting multisensory cognition and to define aging effects on the network’s neuroplastic attributes. A computer-based music reading protocol was developed and evaluated via electroencephalography measurements pre- and post-training on young and older adults. Results revealed that multisensory integration is performed via diverse strategies in the two groups: Older adults employ higher-order supramodal areas to a greater extent than lower level perceptual regions, in contrast to younger adults, indicating an age-related shift in the weight of each processing strategy. Restorative neuroplasticity was revealed in the left inferior frontal gyrus and right medial temporal gyrus, as a result of the training, while task-related reorganization of cortical connectivity was obstructed in the group of older adults, probably due to systemic maturation mechanisms. On the contrary, younger adults significantly increased functional connectivity among the regions supporting multisensory integration.

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Cultural Differences in Susceptibility to Stereotype Threat: France versus India

The Journals of Gerontology Series B ◽

10.1093/geronb/gbaa087 ◽

2020 ◽

Author(s):

Poshita Nicolas ◽

Isabelle Régner ◽

Patrick Lemaire

Keyword(s):

Older Adults ◽

Stereotype Threat ◽

Cultural Differences ◽

Human Cognition ◽

Strategy Selection ◽

Arithmetic Problem ◽

Aging Effects ◽

Cognitive Domains ◽

Cultural Contexts ◽

Age Related

Abstract Objectives Negative aging stereotypes make older adults perform below their true potential in a number of cognitive domains. This phenomenon, known as Age-Based Stereotype Threat, is currently viewed as a powerful factor contributing to an overestimation of cognitive decline in normal aging. However, age-based stereotype threat has been investigated almost exclusively in Western countries. Whether this phenomenon is universal or culture-specific is unknown. Method Here, we first ran a pilot study (N = 106) in which we assessed French and Indian participants’ attitudes towards aging. Then, we assessed stereotype threat effects on arithmetic problem-solving performance and strategies in French and Indian older adults (N = 104). Results We found that French older adults have more negative implicit attitudes towards aging than Indian older adults. We also found that culture modulates age-based stereotype threat effects. Whereas French older adults experienced stereotype threat on both selection and execution of strategies on all arithmetic problems, Indian older adults experienced this threat only in their strategy selection on harder problems. Most interestingly, cultural differences emerged on arithmetic problems under stereotype threat condition, where otherwise no cultural differences were found in the control condition. Discussion Our findings have important implications for understanding how cultural contexts change aging effects on human cognition and age-related difference in cognitive performance.

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Relating resting EEG power spectra to age-related differences in cognitive performance: An observational pilot study

10.1101/2021.02.12.21251655 ◽

2021 ◽

Author(s):

A. Pathania ◽

M. Clark ◽

R. Cowan ◽

M. Euler ◽

K. Duff ◽

...

Keyword(s):

Older Adults ◽

Pilot Study ◽

Power Spectrum ◽

Spatial Working Memory ◽

Memory Task ◽

Mediating Effect ◽

Younger Adults ◽

Eeg Power Spectrum ◽

Age Related ◽

Eeg Power

AbstractBackgroundPrevious research has shown that the slope of the electroencephalography (EEG) power spectrum mediates the difference between older and younger adults on a visuo-spatial working memory task. The present study sought to replicate and extend that work using a larger sample and a validated set of neuropsychological tests: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).MethodsForty-four participants (21 younger adults, 23 older adults) completed a battery of cognitive and motor tasks that included the RBANS. EEG data were collected both during rest and on-task. Excluding the alpha-band, RBANS scores were regressed onto the slope of the resting EEG power spectrum, controlling for age and using robust mediation analysis.ResultsOlder adults performed reliably lower on the RBANS composite and the Coding, List Recall, List Recognition, and Figure Recall subtests. However, boot-strapped mediation models only showed a mediating effect of the spectral slope on RBANS composite and the Coding subtest.ConclusionsThe resting slope of the EEG power spectrum mediated age-related differences in cognition in the current study, which replicates prior work and is consistent with the neural noise hypothesis of aging. In extending this work, it was shown that these effects are strongest in tasks requiring speeded processing and/or executive functions, whereas this effect was weaker (to absent) for delayed memory, even though age-related differences were present. This pilot study warrants further exploration of the EEG power spectrum in age-related cognitive decline.

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Gravity effects are better optimized by older than young adults when reaching with the non-dominant arm

10.1101/2021.10.26.465988 ◽

2021 ◽

Author(s):

Gabriel Poirier ◽

Charalambos Papaxanthis ◽

Adrien Juranville ◽

Mélanie Lebigre ◽

France Mourey ◽

...

Keyword(s):

Older Adults ◽

Young Adults ◽

Motor Control ◽

Control Process ◽

Open Loop ◽

Emg Activity ◽

Aging Effects ◽

Arm Kinematics ◽

Age Related ◽

Gravity Effects

Motor lateralization refers to differences in the neural organization of cerebral hemispheres, resulting in different control specializations between the dominant and the non-dominant motor systems. Multiple studies proposed that the dominant hemisphere is specialized for open-loop optimization-like processes. Recently, comparing arm kinematics between upward and downward movements, we found that the dominant arm outperformed the non-dominant one regarding gravity-related motor optimization in healthy young subjects. The literature about aging effects on motor control presents several neurophysiological and behavioral evidences for an age-related reduction of motor lateralization. Here, we compare the lateralization of a well-known gravity-related optimal motor control process between young and older adults. Thirty healthy young (mean age = 24.1 ± 3 years) and nineteen healthy older adults (mean age = 73.0 ± 8) performed single degree-of-freedom vertical arm movements between two targets (upward and downward). Participants alternatively reached with their dominant and non-dominant arms. We recorded arm kinematics and electromyographic activities of the prime movers (Anterior and Posterior Deltoids) and we analyzed parameters thought to represent the hallmark of the gravity-related optimization process (i.e directional asymmetries and negative epochs on the phasic EMG activity). We found no arm difference in older participants, such that parameters with both arms were similar to those of young participants with their dominant arm. With the non-dominant arm, these results suggest that older adults better optimize gravity effects than young adults.

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