The auditory cortex morphometry predicts variations in hearing acuity: a preliminary study

Abstract Background The auditory cortex plays a vital role in hearing acuity processing . This study aimed to evaluate the relationship between hearing acuity and the morphometry of the auditory cortex to investigate whether declines in hearing acuity correlate with changes in auditory cortex morphology. Methods Twenty-six healthy individuals participated in this study, which used a Siemens 3T Trio MRI scanner with a standard eight-channel head coil. Surface-based morphometry (SBM) was employed to evaluate the neurite architecture in the auditory cortex, encompassing cortical thickness, gyrification, sulcal depth, fractal dimension, and cortical volume. Results The findings showed a significant difference in auditory cortical thickness in the left hemisphere between males (2.41 ± 0.28 mm) and females (2.64 ± 0.27 mm). A significant positive correlation was observed between the fractal dimension of the left auditory cortex and HADS scores ( r = 0.42). Significant negative correlations were also found between participants' ages and auditory cortical thickness in both the left ( r = − 0.58) and right ( r = − 0.71) hemispheres, as well as between the sulcal depth of the right auditory cortex and HADS ( r = − 0.46), and between the cortical thickness of the right auditory cortex and hearing loss threshold (HLT) ( r = − 0.42). Effect size analysis for hemispheric differences indicated a rightward lateralization of auditory cortex thickness (0.03 ± 0.08), gyrification (0.04 ± 0.13), fractal dimension (0.05 ± 0.08), and volume (0.16 ± 0.12), while non-directional asymmetry was observed in sulcal depth (0 ± 0.02). Conclusion A key finding of this research is that the cortical thickness of the auditory cortex was more significantly affected than other markers.