Bridging the brain structure—brain function gap in prosodic speech processing in older adults

To provide a critical evaluation of studies examining the contribution of changes in language-specific cognitive abilities to the speech perception difficulties of older adults. A review of the literature on aging and speech perception. The research considered in the present review suggests that age-related changes in absolute sensitivity is the principal factor affecting older listeners' speech perception in quiet. However, under less favorable listening conditions, changes in a number of speech-specific cognitive abilities can also affect spoken language processing in older people. Clinically, these findings suggest that hearing aids, which have been the traditional treatment for improving speech perception in older adults, are likely to offer considerable benefit in quiet listening situations because the amplification they provide can serve to compensate for age-related hearing losses. However, such devices may be less beneficial in more natural environments, (e.g., noisy backgrounds, multiple talkers, reverberant rooms) because they are less effective for improving speech perception difficulties that result from age-related cognitive declines. It is suggested that an integrative approach to designing test batteries that can assess both sensory and cognitive abilities needed for processing spoken language offers the most promising approach for developing therapeutic interventions to improve speech perception in older adults.

Development of cortical thickness and surface area in autism spectrum disorder.

Previous studies have found that perception in older people benefits from multisensory over unisensory information. As normal speech recognition is affected by both the auditory input and the visual lip movements of the speaker, we investigated the efficiency of audio and visual integration in an older population by manipulating the relative reliability of the auditory and visual information in speech. We also investigated the role of the semantic context of the sentence to assess whether audio–visual integration is affected by top-down semantic processing. We presented participants with audio–visual sentences in which the visual component was either blurred or not blurred. We found that there was a greater cost in recall performance for semantically meaningless speech in the audio–visual ‘blur’ compared to audio–visual ‘no blur’ condition and this effect was specific to the older group. Our findings have implications for understanding how aging affects efficient multisensory integration for the perception of speech and suggests that multisensory inputs may benefit speech perception in older adults when the semantic content of the speech is unpredictable.

Older adults exhibit augmented renal vasoconstriction during orthostatic stress compared to young adults. Consumption of omega‐3 polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fish oil (FO), modulates autonomic nerve activity. However, the effect of omega‐3 polyunsaturated fatty acid consumption on the renal vasoconstrictor response to orthostatic stress in young and older adults is unknown. Therefore, 10 young (25 ± 1 years; mean ± SEM) and 10 older (66 ± 2 years) healthy adults ingested 4 g FO daily for 12 weeks, and underwent graded lower body negative pressure (LBNP; −15 and −30 mmHg) pre‐ and post‐FO supplementation. Renal blood flow velocity (RBFV; Doppler ultrasound), arterial blood pressure (BP; photoplethysmographic finger cuff), and heart rate (electrocardiogram) were recorded. Renal vascular resistance (RVR), an index of renal vasoconstriction, was calculated as mean BP/RBFV. All baseline cardiovascular values were similar between groups and visits, except diastolic BP was higher in the older group (P < 0.05). FO supplementation increased erythrocyte EPA and DHA content in both groups (P < 0.05). FO did not affect RVR or RBFV responses to LBNP in either group, but attenuated the mean BP response to LBNP in the older group (older −30 mmHg: pre‐FO −4 ± 1 vs. post‐FO 0 ± 1 mmHg, P < 0.05; young −30 mmHg: pre‐FO −5 ± 1 vs. post‐FO −5 ± 2 mmHg). In conclusion, FO supplementation attenuates the mean BP response but does not affect the renal vasoconstrictor response to orthostatic stress in older adults.

Speech motor resources may be recruited to assist challenging speech perception in younger normally hearing listeners, but the extent to which this occurs for older adult listeners is unclear. We investigated if speech motor resources are also recruited in older adults during speech perception. Specifically, we investigated if suppression of speech motor resources via sub-vocal rehearsal affects speech perception compared to non-speech motor suppression (jaw movement) and passive listening. Participants identified words in speech-shaped noise at signal-to-noise ratios (SNRs) from -16 to +16 dB in three listening conditions during which participants: (1) opened and closed their jaw (non-speech movement); (2) sub-vocally mimed ‘the’ (articulatory suppression); (3) produced no concurrent movement (passive listening). Data from 46 younger adults (M age = 20.17 years, SD = 1.61, 36 female) and 41 older adults (M age = 69 years, SD = 5.82, 21 female) were analysed. Linear mixed effects modelling investigated the impact of age, listening condition, and self-reported hearing ability on speech perception (d’ prime). Results indicated that speech perception ability was significantly worse in older adults relative to younger adults across all listening conditions. A significant interaction between age group and listening condition indicated that younger adults showed poorer performance during articulatory suppression compared to passive listening, but older adults performed equivalently across conditions. This finding suggests that speech motor resources are less available to support speech perception in older adults, providing important insights for auditory-motor integration for speech understanding and communication in ageing.

The effects of heart failure (HF) on cortical brain structure remain unclear. Therefore, the present study aimed to investigate the causal effects of heart failure on cortical structures in the brain using Mendelian randomization (MR) analysis. We conducted a two-sample MR analysis utilizing genetically-predicted HF trait, left ventricular ejection fraction (LVEF), and N-terminal prohormone brain natriuretic peptide (NT-proBNP) levels to examine their effects on the cortical surface area (SA) and thickness (TH) across 34 cortical brain regions. Genome-wide association study summary data were extracted from studies by Rasooly (1,266,315 participants) for HF trait, Schmidt (36,548 participants) for LVEF, the SCALLOP consortium (21,758 participants) for NT-proBNP, and the ENIGMA Consortium (51,665 participants) for cortical SA and TH. A series of MR analyses were employed to exclude heterogeneity and pleiotropy, ensuring the stability of the results. Given the exploratory nature of the study, p-values between 1.22E-04 and 0.05 were considered suggestive of association, and p-values below 1.22E-04 were defined as statistically significant. In this study, we found no significant association between HF and cortical TH or SA (all p > 1.22E-04). We found that the HF trait and elevated NT-proBNP levels were not associated with cortical SA, but were suggested to decrease cortical TH in the pars orbitalis, lateral orbitofrontal cortex, temporal pole, lingual gyrus, precuneus, and supramarginal gyrus. Reduced LVEF was primarily suggested to decrease cortical SA in the isthmus cingulate gyrus, frontal pole, postcentral gyrus, cuneus, and rostral middle frontal gyrus, as well as TH in the postcentral gyrus. However, it was suggested to causally increase in the SA of the posterior cingulate gyrus and medial orbitofrontal cortex and the TH of the entorhinal cortex and superior temporal gyrus. We found 15 brain regions potentially affected by HF, which may lead to impairments in cognition, emotion, perception, memory, language, sensory processing, vision, and executive control in HF patients.

Ambiguity is ubiquitous in language; lexical ambiguity refers to instances where a single word has multiple meanings. The current investigation examined homonyms, words that have the same orthography and pronunciation in English but multiple meanings (e.g., BANK, meaning "financial institution" or "river's edge"). The processing of homonyms requires the engagement of executive control processes, for example, to select the appropriate meaning of the homonym while reducing interference from other meanings. Executive function processes are known to change over the lifespan and may be impacted by experiential factors such as bilingualism. The present study uses event-related brain potentials as an index of lexical access to examine whether bilingualism influences homonym processing in older adults. The results indicate that patterns of lexical access differ as a function of bilingual status in older adults and compared to young adults, suggesting that language experience may moderate language processing in both young and older adults, at least in situations where language processing is demanding on executive function, such as in the processing of homonyms. Importantly, we show that older bilinguals show a somewhat similar pattern of ambiguity processing as their younger counterparts, while age differences were observed in monolinguals when comparing across studies. This suggests that bilingual language experience may have a mitigating impact on age-related changes in ambiguity processing. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

IntroductionReal time modulation of brainstem frequency-following responses (FFRs) by online changes in cortical arousal state via the corticofugal (top-down) pathway has been demonstrated previously in young adults and is more prominent in the presence of background noise. FFRs during high cortical arousal states also have a stronger relationship with speech perception. Aging is associated with increased auditory brain responses, which might reflect degraded inhibitory processing within the peripheral and ascending pathways, or changes in attentional control regulation via descending auditory pathways. Here, we tested the hypothesis that online corticofugal interplay is impacted by age-related hearing loss.MethodsWe measured EEG in older adults with normal-hearing (NH) and mild to moderate hearing-loss (HL) while they performed speech identification tasks in different noise backgrounds. We measured α power to index online cortical arousal states during task engagement. Subsequently, we split brainstem speech-FFRs, on a trial-by-trial basis, according to fluctuations in concomitant cortical α power into low or high α FFRs to index cortical-brainstem modulation.ResultsWe found cortical α power was smaller in the HL than the NH group. In NH listeners, α-FFRs modulation for clear speech (i.e., without noise) also resembled that previously observed in younger adults for speech in noise. Cortical-brainstem modulation was further diminished in HL older adults in the clear condition and by noise in NH older adults. Machine learning classification showed low α FFR frequency spectra yielded higher accuracy for classifying listeners’ perceptual performance in both NH and HL participants. Moreover, low α FFRs decreased with increased hearing thresholds at 0.5–2 kHz for clear speech but noise generally reduced low α FFRs in the HL group.DiscussionCollectively, our study reveals cortical arousal state actively shapes brainstem speech representations and provides a potential new mechanism for older listeners’ difficulties perceiving speech in cocktail party-like listening situations in the form of a miss-coordination between cortical and subcortical levels of auditory processing.

To determine whether significant differences in cochlear implant (CI) performance exist between older and younger CI recipients. Retrospective comparison of audiometric data. University hospital center. Sixty participants who received CIs at age 70 and older and 48 younger adults implanted between age 18 and 69. Speech outcome scores (Consonant-Nucleus-Consonant words and phonemes and City University of New York Sentence test in quiet and noise). Older participants show significant improvement in speech perception scores after implantation. Although on average they do not perform as well as younger adults, this difference correlates with duration of deafness rather than age. In contrast to younger adults, significant differences in CI performance are seen in older recipients depending on the side of implantation, with those implanted on the right performing better than those implanted on the left. Postlingually deafened older adults obtained significant speech perception benefits from CIs, although differences in speech outcomes were seen between younger recipients and those implanted after age 70. In older adults considering CIs, hearing benefits appear greater if they are implanted in the right ear.

Speech-in-noise (SIN) perception is one of the most complex tasks faced by listeners on a daily basis. Although listening in noise presents challenges for all listeners, background noise inordinately affects speech perception in older adults and in children with learning disabilities. Hearing thresholds are an important factor in SIN perception, but they are not the only factor. For successful comprehension, the listener must perceive and attend to relevant speech features, such as the pitch, timing, and timbre of the target speaker's voice. Here, we review recent studies linking SIN and brainstem processing of speech sounds. To review recent work that has examined the ability of the auditory brainstem response to complex sounds (cABR), which reflects the nervous system's transcription of pitch, timing, and timbre, to be used as an objective neural index for hearing-in-noise abilities. We examined speech-evoked brainstem responses in a variety of populations, including children who are typically developing, children with language-based learning impairment, young adults, older adults, and auditory experts (i.e., musicians). In a number of studies, we recorded brainstem responses in quiet and babble noise conditions to the speech syllable /da/ in all age groups, as well as in a variable condition in children in which /da/ was presented in the context of seven other speech sounds. We also measured speech-in-noise perception using the Hearing-in-Noise Test (HINT) and the Quick Speech-in-Noise Test (QuickSIN). Children and adults with poor SIN perception have deficits in the subcortical spectrotemporal representation of speech, including low-frequency spectral magnitudes and the timing of transient response peaks. Furthermore, auditory expertise, as engendered by musical training, provides both behavioral and neural advantages for processing speech in noise. These results have implications for future assessment and management strategies for young and old populations whose primary complaint is difficulty hearing in background noise. The cABR provides a clinically applicable metric for objective assessment of individuals with SIN deficits, for determination of the biologic nature of disorders affecting SIN perception, for evaluation of appropriate hearing aid algorithms, and for monitoring the efficacy of auditory remediation and training.

Variations in brain morphometry among healthy preschoolers born preterm

Relationships between cortical brain structure and neurocognitive functioning have been reported in schizophrenia, but findings are inconclusive, and only a few studies in bipolar disorder have addressed this issue. This is the first study to directly compare relationships between cortical thickness and surface area with neurocognitive functioning in patients with schizophrenia (n = 117) and bipolar disorder (n = 121) and healthy controls (n = 192). MRI scans were obtained, and regional cortical thickness and surface area measurements were analyzed for relationships with test scores from 6 neurocognitive domains. In the combined sample, cortical thickness in the right rostral anterior cingulate was inversely related to working memory, and cortical surface area in four frontal and temporal regions were positively related to neurocognitive functioning. A positive relationship between left transverse temporal thickness and processing speed was specific to schizophrenia. A negative relationship between right temporal pole thickness and working memory was specific to bipolar disorder. In conclusion, significant cortical structure/function relationships were found in a large sample of healthy controls and patients with schizophrenia or bipolar disorder. The differences that were found between schizophrenia and bipolar may indicate differential relationship patterns in the two disorders, which may be of relevance for understanding the underlying pathophysiology.

Previous neuroimaging studies on resilience have generally compared resilience and psychopathology after stress exposure, which does not allow for conclusions regarding correlates specific to resilience. The aim of the present study was to investigate resilience‐specific correlates in cortical thickness and/or cortical surface area and their correlations with psychometric measurements, using a three‐group design that included a non–trauma‐exposed control group in order to disentangle effects related to resilience from those related to psychopathology. Structural magnetic resonance imaging scans were acquired from 82 Dutch police officers. Participants were categorized into resilient (n = 31; trauma exposure, no psychopathology), vulnerable (n = 32; trauma exposure, psychopathology), and control groups (n = 19; no trauma exposure, no psychopathology). Specific regions of interest (ROIs) were identified based on previous studies that found the rostral and caudal anterior cingulate cortex (ACC) to be implicated in trauma‐related psychopathology. Cortical thickness and surface area of the ROIs—the rostral and caudal ACC—and of the whole brain were examined. No significant differences in cortical thickness or surface area were found between the resilient group and other groups in the ROI and whole‐brain analyses. Thus, the results of the present study provide no evidence of an association between resilience to traumatic stress and measures of thickness and surface area in cortical regions of the brain in a sample of Dutch police officers.

Cortical neurite microstructural correlates of time perception in healthy older adults

要旨: ことばの聞き取りに重要な時間情報の処理には, 時間分解能が関係している。本研究では, 純音聴力レベルが 20dBHL 以下の高齢者15名 (平均年齢: 71.4歳) を対象に, ギャップ前後の刺激音の周波数を変化させた (条件①: 800-1600Hz, 条件②: 800-3200Hz), 周波数間ギャップ検出閾値検査を実施した。ギャップサイズは 150ms から適応法にて 1up-2down で上下するよう設定し, ギャップ検出閾値を求め, 若年者と比較した。高齢者は若年者に比し,有意に閾値上昇を認めた。また高齢者に複数の聴取検査を実施し, ギャップ検出閾値と語音聴取との関係を検討した。条件①②共に聴覚的注意検査と, 条件②と複数音声下聴取検査で相関を認めた。周波数間ギャップ検出閾値は, 注意のシフトのような何らかの注意機能が関与すると言われている。高齢者は聴力だけでなく, 認知機能も聞き取りに影響を及ぼすとされる。加齢の影響がどのように認知機能や聴取に影響を及ぼすか, 聞き取りを多面的に捉えることが重要である。