Alterations of Excitation–Inhibition Balance and Brain Network Dynamics Support Sensory Deprivation Theory in Presbycusis

Human Brain Mapping, Journal Year: 2024, Volume and Issue: 45(16)

Published: Nov. 1, 2024

ABSTRACT Sensory deprivation theory is an important hypothesis involving potential pathways between hearing loss and cognitive impairment in patients with presbycusis. The suggests that prolonged auditory presbycusis, including neural deafferentation, cortical reallocation, atrophy, causes long‐lasting changes reorganization brain structure function. However, neurophysiological underlying the cognition‐ear link have not been explored. In this study, we recruited 98 presbycusis 60 healthy controls examined differences two groups gamma‐aminobutyric acid (GABA) glutamate (Glu) levels bilateral cortex, excitation–inhibition (E/I) balance (Glu/GABA ratio), dynamic functional network connectivity (dFNC), ability performance. Then, correlations each other were investigated variables statistical significance further analyzed using PROCESS Macro SPSS. GABA right cortex Glu lower but E/I higher compared to controls. Hearing assessments performance worse patients. Three recurring states identified after dFNC analysis: State 1 (least frequent, middle‐high strength negative connectivity), 2 (high strength), 3 (most low strength). occurrence dwell time of higher, on hand, decreased cognition correlated levels, increased balance, aberrant dFNC, 3. mediation model, fractional windows, as well 3, mediated relationship episodic memory (Auditory Verbal Learning Test, AVLT) Moreover, found contribute impact which caused AVLT scores. Overall, results suggest a shift plays role provide evidence for sensory theory, enhancing our understanding connection patients, may serve neuroimaging marker exploring predicting impairment.

Language: Английский

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Environmental enrichment is associated with favorable memory-related functional brain activity patterns in older adults

Frontiers in Aging Neuroscience, Journal Year: 2024, Volume and Issue: 16

Published: Dec. 24, 2024

Background In humans, environmental enrichment (EE), as measured by the engagement in a variety of leisure activities, has been associated with larger hippocampal structure and better memory function. The present cross-sectional study assessed whether EE during early life (13–30 years) midlife (30–65 is preserved memory-related brain activity patterns older age. Methods total, 372 cognitively unimpaired adults (aged ≥60 years old) DZNE-Longitudinal Study on Cognitive Impairment Dementia (DELCODE; DRKS00007966) were investigated. was operationalized using items Lifetime Experiences Questionnaire (LEQ), which measures self-reported participation activities midlife. preservation functional single-value scores, relate adults’ temporo-parieto-occipital network to those young visual encoding (FADE SAME scores). Results significantly higher scores novelty processing ( n = 372, β 0.13, p 0.011). Thus, participants showed greater similarity adults. This positive association observed most strongly subjective cognitive decline (SCD, 199, 0.20, 0.006). Conclusion More frequent more successful aging adults, including at increased risk for dementia. Longitudinal studies are needed clarify could help preserve function later life.

Language: Английский

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Single-value fMRI scores reflect both stage and risk across the Alzheimer’s disease continuum

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Oct. 12, 2023

Abstract Single-value scores reflecting the deviation from (FADE score) or similarity with (SAME prototypical novelty-related and memory-related functional magnetic resonance imaging (fMRI) activation patterns in young adults have been proposed as biomarkers of healthy neurocognitive aging. Here, we tested utility these potential diagnostic prognostic markers Alzheimer’s disease (AD) risk states like mild cognitive impairment (MCI) subjective decline (SCD). To this end, analyzed subsequent memory fMRI data individuals SCD, MCI, AD dementia well controls (HC) first-degree relatives patients (AD-rel) who participated multi-center DELCODE study (N = 468). Based on individual participants’ whole-brain novelty responses, calculated FADE SAME assessed their association stage, neuropsychological test scores, CSF amyloid positivity, ApoE genotype. Memory-based showed a considerably larger reference sample MCI groups compared to HC, SCD AD-rel. In addition, novelty-based significantly differed between groups. Across entire sample, single-value correlated performance. The score further Aβ-positive Aβ-negative AD-rel, ε4 carriers non-carriers Hence, are associated both performance factors for AD. Their warrants exploration, particularly patients.

Language: Английский

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Inhibitory temporo-parietal effective connectivity is associated with explicit memory performance in older adults

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Dec. 23, 2022

Abstract Successful explicit memory encoding is associated with inferior temporal activations and medial parietal deactivations, which are attenuated in aging. Here we used Dynamic Causal Modeling (DCM) of functional magnetic resonance imaging data to elucidate effective connectivity patterns between hippocampus, parahippocampal place area (PPA) precuneus during novel visual scenes. In 117 young adults, DCM revealed pronounced activating input from the PPA hippocampus inhibitory novelty processing, both being enhanced successful encoding. This pattern could be replicated two cohorts (N = 141 148) older adults. cohorts, adults selectively exhibited PPA-precuneus connectivity, correlated negatively performance. Our results provide insight into network dynamics underlying suggest that age-related differences memory-related activity are, at least partly, attributable altered temporo-parietal neocortical connectivity.

Language: Английский

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