Age-related changes in excitatory and inhibitory intra-cortical circuits in auditory cortex of C57Bl/6 mice

Research trends and hotspot analysis of age-related hearing loss: A bibliometric analysis from 2019 to 2023

BACKGROUND

Age-related hearing loss (ARHL) - also termed presbycusis - is prevalent among older adults, leading to a range of issues. Although considerable progress in the understanding of ARHL over the decades, available reports lack data from recent years and do not comprehensively reflect the latest advancements and trends. Therefore, our study sought to assess research hotspots and trends in ARHL over the past 5 years to provide the basis for future research.

MATERIALS AND METHODS

The Web of Science Core Collection database was searched and screened from January 1, 2019 to October 21, 2023, according to the inclusion criteria. CiteSpace (5.8.R3), VOSviewer (1.6.19), and Microsoft Excel 2019 were employed for bibliometric analysis and visualization.

RESULTS

3084 articles from 92 countries led by the United States and China were included. There has been a steady upward trend in the number of publications from 2019 to 2023. The most productive institutions, authors, and journals are Johns Hopkins University (n = 113), Lin FR (n = 66), and Ear and Hearing (n = 135), respectively. Trend topic analyses revealed that "cochlear synaptopathy" and "dementia" were the predominant foci. Keywords, including "individuals" and "national health", began to appear.

CONCLUSION

Over the past 5 years, the annual number of publications has increased significantly and will continue to do so. Research on the mechanism of ARHL, represented by "oxidative stress", is a continuing focus. Emerging topics such as "individual differences" and "national health" may be potential future hotspots in this field.

Long-term training alters response dynamics in the aging auditory cortex

Age-related auditory dysfunction, presbycusis, is caused in part by functional changes in the auditory cortex (ACtx) such as altered response dynamics and increased population correlations. Given the ability of cortical function to be altered by training, we tested if performing auditory tasks might benefit auditory function in old age. We examined this by training adult mice on a low-effort tone-detection task for at least six months and then investigated functional responses in ACtx at an older age (∼18 months). Task performance remained stable well into old age. Comparing sound-evoked responses of thousands of ACtx neurons using in vivo 2-photon Ca2+ imaging, we found that many aspects of youthful neuronal activity, including low activity correlations, lower neural excitability, and a greater proportion of suppressed responses, were preserved in trained old animals as compared to passively-exposed old animals. Thus, consistent training on a low-effort task can benefit age-related functional changes in ACtx and may preserve many aspects of auditory function.