Musical training can counteract age-related decline in speech perception in noisy environments. However, it remains unclear whether older non-musicians and musicians rely on functional compensation or functional preservation to counteract the adverse effects of aging. This study utilized resting-state functional connectivity (FC) to investigate functional lateralization, a fundamental organization feature, in older musicians (OM), older non-musicians (ONM), and young non-musicians (YNM). Results showed that OM outperformed ONM and achieved comparable performance to YNM in speech-in-noise and speech-in-speech tasks. ONM exhibited reduced lateralization than YNM in lateralization index (LI) of intrahemispheric FC (LI_intra) in the cingulo-opercular network (CON) and LI of interhemispheric heterotopic FC (LI_he) in the language network (LAN). Conversely, OM showed higher neural alignment to YNM (i.e., a more similar lateralization pattern) compared to ONM in CON, LAN, frontoparietal network (FPN), dorsal attention network (DAN), and default mode network (DMN), indicating preservation of youth-like lateralization patterns due to musical experience. Furthermore, in ONM, stronger left-lateralized and lower alignment-to-young of LI_intra in the somatomotor network (SMN) and DAN and LI_he in DMN correlated with better speech performance, indicating a functional compensation mechanism. In contrast, stronger right-lateralized LI_intra in FPN and DAN and higher alignment-to-young of LI_he in LAN correlated with better performance in OM, suggesting a functional preservation mechanism. These findings highlight the differential roles of functional preservation and compensation of lateralization in speech perception in noise among elderly individuals with and without musical expertise, offering insights into successful aging theories from the lens of functional lateralization and speech perception.
Humans ; Speech Perception/physiology* ; Music ; Male ; Functional Laterality/physiology* ; Female ; Aged ; Adult ; Young Adult ; Aging/physiology* ; Middle Aged ; Magnetic Resonance Imaging ; Brain/physiology*

BACKGROUNDIt is desirable to minimize the risk of adverse radiation effects associated with percutaneous coronary intervention. The aim of this study was to determine the impact of prolonging the interval between coronary angiography and percutaneous coronary intervention on X-ray-induced DNA double-strand breaks in blood lymphocytes using γ-H2AX immunofluorescence microscopy.

METHODSBlood samples of eight patients were taken before the first exposure to ionizing radiation, 10 minutes, 20 minutes, 30 minutes, 1 hour, and 24 hours after the last exposure to determine the γ-H2AX foci repair kinetics. Fifty-eight patients undergoing percutaneous coronary intervention were randomized to an intermittent radiation exposure group and a continuous radiation exposure group. Blood samples were taken before coronary angiography and 15 minutes after the last exposure. By enumerating γ-H2AX foci, the impact of prolonging the interval on DNA double-strand breaks was investigated. Student t-test was used to compare the difference in DNA double-strand breaks between the two groups.

RESULTSAn increase in foci was found in all patients received percutaneous coronary intervention. The maximum number of γ-H2AX foci was found 10-20 minutes after the end of the last exposure. There was no statistically significant difference between the two groups in γ-H2AX foci at baseline. On average there were (0.79 ± 0.15) γ-H2AX foci induced by interventional X-rays per lymphocyte in the continuous radiation exposure group and (0.66 ± 0.21) in the intermittent radiation exposure group after exposure (P < 0.05).

CONCLUSIONSA significant number of γ-H2AX foci develop following the percutaneous coronary intervention procedures. The number of X-ray-induced DNA double-strand breaks may be decreased by prolonging the interval time between coronary angiography and percutaneous coronary intervention to 30 minutes.

Adult ; Coronary Angiography ; adverse effects ; DNA Breaks, Double-Stranded ; radiation effects ; Dose-Response Relationship, Radiation ; Female ; Humans ; Lymphocytes ; metabolism ; radiation effects ; Male ; Middle Aged ; Percutaneous Coronary Intervention ; adverse effects