Age-related differences in binaural masking level differences: behavioral and electrophysiological evidence

The effects of aging and stimulus configuration on binaural masking level differences (BMLDs) were measured behaviorally and electrophysiologically, using the frequency-following response (FFR) to target brainstem/midbrain encoding. The tests were performed in 15 younger normal-hearing (<30 yr) and 15 older normal-hearing (>60 yr) participants. The stimuli consisted of a 500-Hz target tone embedded in a narrowband (50-Hz bandwidth) or wideband (1,500-Hz bandwidth) noise masker. The interaural phase conditions included NoSo (tone and noise presented interaurally in-phase), NoSπ (noise presented interaurally in-phase and tone presented out-of-phase), and NπSo (noise presented interaurally out-of-phase and tone presented in-phase) configurations. In the behavioral experiment, aging reduced the magnitude of the BMLD. The magnitude of the BMLD was smaller for the NoSo–NπSo threshold difference compared with the NoSo–NoSπ threshold difference, and it was also smaller in narrowband compared with wideband conditions, consistent with previous measurements. In the electrophysiology experiment, older participants had reduced FFR magnitudes and smaller differences between configurations. There were significant changes in FFR magnitude between the NoSo to NoSπ configurations but not between the NoSo to NπSo configurations. The age-related reduction in FFR magnitudes suggests a temporal processing deficit, but no correlation was found between FFR magnitudes and behavioral BMLDs. Therefore, independent mechanisms may be contributing to the behavioral and neural deficits. Specifically, older participants had higher behavioral thresholds than younger participants for the NoSπ and NπSo configurations but had equivalent thresholds for the NoSo configuration. However, FFR magnitudes were reduced in older participants across all configurations. NEW & NOTEWORTHY Behavioral and electrophysiological testing reveal an aging effect for stimuli presented in wideband and narrowband noise conditions, such that behavioral binaural masking level differences and subcortical spectral magnitudes are reduced in older compared with younger participants. These deficits in binaural processing may limit the older participant's ability to use spatial cues to understand speech in environments containing competing sound sources.

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Mutual information analysis of neural representations of speech in noise in the aging midbrain

Journal of Neurophysiology ◽

10.1152/jn.00270.2019 ◽

2019 ◽

Vol 122 (6) ◽

pp. 2372-2387 ◽

Cited By ~ 3

Author(s):

Peng Zan ◽

Alessandro Presacco ◽

Samira Anderson ◽

Jonathan Z. Simon

Keyword(s):

Older Adults ◽

Mutual Information ◽

Normal Hearing ◽

Information Analysis ◽

Frequency Following Response ◽

Speech In Noise ◽

Clinically Normal ◽

Age Related ◽

Competing Speech ◽

Mutual Information Analysis

Younger adults with normal hearing can typically understand speech in the presence of a competing speaker without much effort, but this ability to understand speech in challenging conditions deteriorates with age. Older adults, even with clinically normal hearing, often have problems understanding speech in noise. Earlier auditory studies using the frequency-following response (FFR), primarily believed to be generated by the midbrain, demonstrated age-related neural deficits when analyzed with traditional measures. Here we use a mutual information paradigm to analyze the FFR to speech (masked by a competing speech signal) by estimating the amount of stimulus information contained in the FFR. Our results show, first, a broadband informational loss associated with aging for both FFR amplitude and phase. Second, this age-related loss of information is more severe in higher-frequency FFR bands (several hundred hertz). Third, the mutual information between the FFR and the stimulus decreases as noise level increases for both age groups. Fourth, older adults benefit neurally, i.e., show a reduction in loss of information, when the speech masker is changed from meaningful (talker speaking a language that they can comprehend, such as English) to meaningless (talker speaking a language that they cannot comprehend, such as Dutch). This benefit is not seen in younger listeners, which suggests that age-related informational loss may be more severe when the speech masker is meaningful than when it is meaningless. In summary, as a method, mutual information analysis can unveil new results that traditional measures may not have enough statistical power to assess. NEW & NOTEWORTHY Older adults, even with clinically normal hearing, often have problems understanding speech in noise. Auditory studies using the frequency-following response (FFR) have demonstrated age-related neural deficits with traditional methods. Here we use a mutual information paradigm to analyze the FFR to speech masked by competing speech. Results confirm those from traditional analysis but additionally show that older adults benefit neurally when the masker changes from a language that they comprehend to a language they cannot.

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The Effects of Aging on Speech Perception in Noise: Comparison between Normal-Hearing and Cochlear-Implant Listeners

Journal of the American Academy of Audiology ◽

10.3766/jaaa.25.7.4 ◽

2014 ◽

Vol 25 (07) ◽

pp. 656-665 ◽

Cited By ~ 14

Author(s):

Su-Hyun Jin ◽

Chang Liu ◽

Douglas P. Sladen

Keyword(s):

Speech Recognition ◽

Aging Effect ◽

Speech Understanding ◽

Detection Thresholds ◽

Speech Perception In Noise ◽

Sentence Recognition ◽

Hearing Status ◽

Age Related ◽

Effects Of Aging ◽

Speech Recognition In Noise

Background: Speech understanding in noise is comparatively more problematic for older listeners with and without hearing loss, and age-related changes in temporal resolution might be associated with reduced speech recognition in complex noise. Purpose: The purpose of this study was to investigate the effects of aging on temporal processing and speech perception in noise for normal-hearing (NH) and cochlear-implant (CI) listeners. Research Design: All participants completed three experimental procedures: (1) amplitude modulation (AM) detection thresholds, (2) sentence recognition in quiet, and (3) speech recognition in steady or modulating noise. Study Sample: Four listener groups participated in the study: 11 younger (≤ 30 yr old, YNH) listeners and 12 older (> 60 yr old, ONH) listeners with NH and 7 younger (< 55 yr old, YCI) and 6 older (> 60 yr old, OCI) CI users. CI listeners have been wearing their device either monaurally or binaurally at least 1 yr. Data collection and Analysis: For speech recognition testing, there were eight listening conditions in noise (4 modulation frequencies × 2 signal-to-noise ratios) and one in quiet for each listener. For modulation detection testing, a broadband noise with a duration of 500 msec served as the stimuli at three temporal modulation frequencies of 2, 4, and 8 Hz, which were used to modulate the noise in the speech recognition experiment. We measured AM detection thresholds using a two-interval, two-alternative, forced-choice adaptive procedure. We conducted a series of analysis of variance tests to examine the effect of aging on each test result and measured the correlation coefficient between speech recognition in noise and modulation detection thresholds. Results: Although older NH and CI listeners performed similar to the younger listeners with the same hearing status for sentence recognition in quiet, there was a significant aging effect on speech recognition in noise. Regardless of modulation frequency and signal-to-noise ratio, speech recognition scores of the older listeners were poorer than those of the younger listeners when hearing status was matched. We also found a significant effect of aging on AM detection at each modulating frequency and a strong correlation between speech recognition in modulating noise and AM detection thresholds at 2 and 4 Hz. Conclusions: Regardless of differences in hearing status, the degree and pattern of aging effect on auditory processing of the NH listener groups were similar to those of the CI listener groups. This result suggests that age-related declines in speech understanding are likely multifactorial, including peripheral and central factors. Although the age cutoff of the current older age group was 10 yr less than in previous studies (Dubno et al, 2002; Lin et al, 2011), we still found the age-related differences on two auditory tasks. This study extends the knowledge of age-related auditory perception difficulties to CI listeners.

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Mutual Information Analysis of Neural Representations of Speech in Noise in the Aging Midbrain

10.1101/619528 ◽

2019 ◽

Author(s):

Peng Zan ◽

Alessandro Presacco ◽

Samira Anderson ◽

Jonathan Z. Simon

Keyword(s):

Older Adults ◽

Mutual Information ◽

Normal Hearing ◽

Information Analysis ◽

Frequency Following Response ◽

Speech In Noise ◽

Clinically Normal ◽

Age Related ◽

Competing Speech ◽

Mutual Information Analysis

AbstractYounger adults with normal hearing can typically understand speech in the presence of a competing speaker without much effort, but this ability to understand speech in challenging conditions deteriorates with age. Older adults, even with clinically normal hearing, often have problems understanding speech in noise. Earlier auditory studies using the frequency-following response (FFR), primarily believed generated by the midbrain, have demonstrated age-related neural deficits when analyzed using traditional measures. Here we use a mutual information paradigm to analyze the FFR to speech (masked by a competing speech signal) by estimating the amount of stimulus information contained in the FFR. Our results show, first, a broad-band informational loss associated with aging for both FFR amplitude and phase. Second, this age-related loss of information is more severe in higher frequency FFR bands (several hundred Hz). Third, the mutual information between the FFR and the stimulus decreases as noise level increases for both age groups. Fourth, older adults benefit neurally, i.e., show a reduction in loss of information, when the speech masker is changed from meaningful (talker speaking a language that they can comprehend, such as English) to meaningless (talker speaking a language that they cannot comprehend, such as Dutch). This benefit is not seen in younger listeners, which suggests age-related informational loss may be more severe when the speech masker is meaningful than when it is meaningless. In summary, as a method, mutual information analysis can unveil new results that traditional measures may not have enough statistical power to assess.New & NoteworthyOlder adults, even with clinically normal hearing, often have problems understanding speech in noise. Auditory studies using the frequency-following response (FFR) have demonstrated age-related neural deficits using traditional methods. Here we use a mutual information paradigm to analyze the FFR to speech masked by competing speech. Results confirm those using traditional analysis, but additionally show that older adults benefit neurally when the masker changes from a language that they comprehend to a language they cannot.

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The Age-Sensitive Efficacy of Calorie Restriction on Mitochondrial Biogenesis and mtDNA Damage in Rat Liver

International Journal of Molecular Sciences ◽

10.3390/ijms22041665 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1665

Author(s):

Guglielmina Chimienti ◽

Anna Picca ◽

Flavio Fracasso ◽

Francesco Russo ◽

Antonella Orlando ◽

...

Keyword(s):

Calorie Restriction ◽

Citrate Synthase ◽

Aging Effect ◽

Mtdna Damage ◽

Mitochondrial Markers ◽

Age Related ◽

Efficacious Treatment ◽

Mtdna Deletion ◽

Cyt C ◽

Ad Libitum

Calorie restriction (CR) is the most efficacious treatment to delay the onset of age-related changes such as mitochondrial dysfunction. However, the sensitivity of mitochondrial markers to CR and the age-related boundaries of CR efficacy are not fully elucidated. We used liver samples from ad libitum-fed (AL) rats divided in: 18-month-old (AL-18), 28-month-old (AL-28), and 32-month-old (AL-32) groups, and from CR-treated (CR) 28-month-old (CR-28) and 32-month-old (CR-32) counterparts to assay the effect of CR on several mitochondrial markers. The age-related decreases in citrate synthase activity, in TFAM, MFN2, and DRP1 protein amounts and in the mtDNA content in the AL-28 group were prevented in CR-28 counterparts. Accordingly, CR reduced oxidative mtDNA damage assessed through the incidence of oxidized purines at specific mtDNA regions in CR-28 animals. These findings support the anti-aging effect of CR up to 28 months. Conversely, the protein amounts of LonP1, Cyt c, OGG1, and APE1 and the 4.8 Kb mtDNA deletion content were not affected in CR-28 rats. The absence of significant differences between the AL-32 values and the CR-32 counterparts suggests an age-related boundary of CR efficacy at this age. However, this only partially curtails the CR benefits in counteracting the generalized aging decline and the related mitochondrial involvement.

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Age-related decline in the taurine content of the skin in rodents

Amino Acids ◽

10.1007/s00726-021-02956-2 ◽

2021 ◽

Author(s):

Tomohisa Yoshimura ◽

Yuki Inokuchi ◽

Chikako Mutou ◽

Takanobu Sakurai ◽

Tohru Nagahama ◽

...

Keyword(s):

High Performance ◽

Age Groups ◽

Immunohistochemical Analysis ◽

Sprague Dawley ◽

Taurine Supplementation ◽

Hairless Mice ◽

Age Related ◽

Sprague Dawley Rats ◽

High Concentrations ◽

Effects Of Aging

AbstractTaurine, a sulfur-containing amino acid, occurs at high concentrations in the skin, and plays a role in maintaining the homeostasis of the skin. We investigated the effects of aging on the content and localization of taurine in the skin of mice and rats. Taurine was extracted from the skin samples of hairless mice and Sprague Dawley rats, and the taurine content of the skin was determined by high-performance liquid chromatography (HPLC). The results of the investigation revealed that the taurine content in both the dermis and epidermis of hairless mice declined significantly with age. Similar age-related decline in the skin taurine content was also observed in rats. In contrast, the taurine content in the sole remained unchanged with age. An immunohistochemical analysis also revealed a decreased skin taurine content in aged animals compared with younger animals, although no significant differences in the localization of taurine were observed between the two age groups. Supplementation of the drinking water of aged mice with 3% (w/v) taurine for 4 weeks increased the taurine content of the epidermis, but not the dermis. The present study showed for the first time that the taurine content of the skin decreased with age in mice and rats, which may be related to the impairment of the skin homeostasis observed with aging. The decreased taurine content of the epidermis in aged animals was able to be rescued by taurine supplementation.

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Effects of aging on emotion recognition from dynamic multimodal expressions and vocalizations

Scientific Reports ◽

10.1038/s41598-021-82135-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Diana S. Cortes ◽

Christina Tornberg ◽

Tanja Bänziger ◽

Hillary Anger Elfenbein ◽

Håkan Fischer ◽

...

Keyword(s):

Older Adults ◽

Emotion Recognition ◽

Positive Emotions ◽

Negative Emotions ◽

Group Differences ◽

Significant Group ◽

Positivity Effect ◽

Video Recordings ◽

Age Related ◽

Effects Of Aging

AbstractAge-related differences in emotion recognition have predominantly been investigated using static pictures of facial expressions, and positive emotions beyond happiness have rarely been included. The current study instead used dynamic facial and vocal stimuli, and included a wider than usual range of positive emotions. In Task 1, younger and older adults were tested for their abilities to recognize 12 emotions from brief video recordings presented in visual, auditory, and multimodal blocks. Task 2 assessed recognition of 18 emotions conveyed by non-linguistic vocalizations (e.g., laughter, sobs, and sighs). Results from both tasks showed that younger adults had significantly higher overall recognition rates than older adults. In Task 1, significant group differences (younger > older) were only observed for the auditory block (across all emotions), and for expressions of anger, irritation, and relief (across all presentation blocks). In Task 2, significant group differences were observed for 6 out of 9 positive, and 8 out of 9 negative emotions. Overall, results indicate that recognition of both positive and negative emotions show age-related differences. This suggests that the age-related positivity effect in emotion recognition may become less evident when dynamic emotional stimuli are used and happiness is not the only positive emotion under study.

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Peroxisome Senescence in Human Fibroblasts

Molecular Biology of the Cell ◽

10.1091/mbc.e02-06-0322 ◽

2002 ◽

Vol 13 (12) ◽

pp. 4243-4255 ◽

Cited By ~ 109

Author(s):

Julie E. Legakis ◽

Jay I. Koepke ◽

Chris Jedeszko ◽

Ferdous Barlaskar ◽

Laura J. Terlecky ◽

...

Keyword(s):

Molecular Mechanisms ◽

Protein Import ◽

Human Fibroblasts ◽

Toxic Metabolite ◽

Age Related ◽

Peroxisomal Targeting ◽

Targeting Signal ◽

Effects Of Aging ◽

Antioxidant Enzyme Catalase ◽

Import Receptor

The molecular mechanisms of peroxisome biogenesis have begun to emerge; in contrast, relatively little is known about how the organelle functions as cells age. In this report, we characterize age-related changes in peroxisomes of human cells. We show that aging compromises peroxisomal targeting signal 1 (PTS1) protein import, affecting in particular the critical antioxidant enzyme catalase. The number and appearance of peroxisomes are altered in these cells, and the organelles accumulate the PTS1-import receptor, Pex5p, on their membranes. Concomitantly, cells produce increasing amounts of the toxic metabolite hydrogen peroxide, and we present evidence that this increased load of reactive oxygen species may further reduce peroxisomal protein import and exacerbate the effects of aging.

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Perception of Auditory Distance in Normal-Hearing and Moderate-to-Profound Hearing-Impaired Listeners

Trends in Hearing ◽

10.1177/2331216519887615 ◽

2019 ◽

Vol 23 ◽

pp. 233121651988761 ◽

Cited By ~ 3

Author(s):

Gilles Courtois ◽

Vincent Grimaldi ◽

Hervé Lissek ◽

Philippe Estoppey ◽

Eleftheria Georganti

Keyword(s):

Hearing Loss ◽

Hearing Aids ◽

Normal Hearing ◽

Hearing Impaired ◽

Spatial Cues ◽

Linear Amplification ◽

Profound Hearing Loss ◽

Wireless Microphone ◽

Auditory Distance ◽

Non Linear

The auditory system allows the estimation of the distance to sound-emitting objects using multiple spatial cues. In virtual acoustics over headphones, a prerequisite to render auditory distance impression is sound externalization, which denotes the perception of synthesized stimuli outside of the head. Prior studies have found that listeners with mild-to-moderate hearing loss are able to perceive auditory distance and are sensitive to externalization. However, this ability may be degraded by certain factors, such as non-linear amplification in hearing aids or the use of a remote wireless microphone. In this study, 10 normal-hearing and 20 moderate-to-profound hearing-impaired listeners were instructed to estimate the distance of stimuli processed with different methods yielding various perceived auditory distances in the vicinity of the listeners. Two different configurations of non-linear amplification were implemented, and a novel feature aiming to restore a sense of distance in wireless microphone systems was tested. The results showed that the hearing-impaired listeners, even those with a profound hearing loss, were able to discriminate nearby and far sounds that were equalized in level. Their perception of auditory distance was however more contracted than in normal-hearing listeners. Non-linear amplification was found to distort the original spatial cues, but no adverse effect on the ratings of auditory distance was evident. Finally, it was shown that the novel feature was successful in allowing the hearing-impaired participants to perceive externalized sounds with wireless microphone systems.

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Effect of aging on the chaperone-like function of human α-crystallin assessed by three methods

Biochemical Journal ◽

10.1042/bj3280763 ◽

1997 ◽

Vol 328 (3) ◽

pp. 763-768 ◽

Cited By ~ 28

Author(s):

K. Barry DERHAM ◽

J. John HARDING

Keyword(s):

Protective Effect ◽

Molecular Chaperone ◽

Enzyme Inactivation ◽

Equivalent Age ◽

Age Related ◽

Human Lenses ◽

Effects Of Aging ◽

Soluble Fractions

α-Crystallin can function as a molecular chaperone by preventing unwanted interactions. This paper presents the effects of aging and cataract on the chaperone-like properties of α-crystallin from soluble fractions from the cortex and nucleus of human lenses by using three assays: enzyme inactivation and two turbidity experiments. The three methods complemented each other. There was no decrease with age of chaperone-like function of cortical α-low and α-high crystallin. Nuclear α-low crystallin showed a decrease, whereas α-high crystallin showed no age-related change but its protective effect was diminished. Results from the nucleus of 40-year-old cataractous lenses seemed similar to those for clear lenses of equivalent age, whereas 80-year-old cataractous lenses showed decreased chaperone-like behaviour.

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