Biology subjects

Mercaldo, N.

Publications and source records attributed to Mercaldo, N..

3 recordsLinked to original sources

bioRxiv2026

MEG Signatures of Differences in Auditory Cortex Responses to Trigger versus Non-Trigger Sounds in Misophonia

Misophonia is characterized by intense emotional and physiological reactions to specific trigger sounds that may vary across individuals. Despite greater recognition and increased research, the neural mechanisms underlying misophonia are still poorly understood. Using magnetoencephalography (MEG) with millisecond temporal resolution, we examined auditory cortex responses to trigger versus non-trigger sounds in 23 individuals (ages 14 - 32 years) that met criteria for misophonia on a screening assessment. We found that in the right hemisphere, trigger sounds elicited significantly smaller evoked responses, lower power of evoked alpha-band oscillations, and stronger alpha-gamma cross-frequency phase-amplitude coupling, compared to non-trigger sounds. We also found that evoked responses and power correlated with behaviorally assessed extent of misophonia symptoms. These findings support the idea that misophonia is characterized at least in part by altered neurophysiological processing of auditory trigger stimuli early in auditory cortex hierarchy. Our results provide novel insight into the neural basis of misophonia, and underscore the importance of examining brain activity even at the earliest levels of the cortical hierarchy, especially with high spatio-temporal resolution.

neuroscience↗

bioRxiv2026

Cortical Excitation-Inhibition Balance in Autism Varies by Brain Region and Age

Autism spectrum disorder (ASD) is characterized by differences in social communication, interaction, and restricted and repetitive behaviors. The hypothesis that ASD involves altered cortical excitation-inhibition (EI) balance has been extensively investigated, yet evidence remains mixed, partly because EI balance changes substantially during typical maturation. We used resting-state magnetoencephalography (MEG) to examine developmental trajectories of cortical EI alterations with regional specificity in a large cross-sectional cohort (N = 172; 92 typically developing, 80 ASD; ages 6-32). Functional EI (fEI), derived from critical brain dynamics, was estimated across 500 cortical parcellations. Group-averaged fEI maps revealed broadly similar large-scale topographic patterns across groups. Age-stratified analyses revealed increased global fEI in childhood and decreased fEI in adolescence in ASD, with no evidence of a group difference in adulthood. Parcel-wise regressions identified a significant main effect of diagnosis in right dorsolateral prefrontal cortex, where typically developing individuals showed higher fEI across all ages. A significant group-by-age interaction in left inferior parietal cortex indicated diverging developmental trajectories. Finally, fEI in paracentral and precuneus regions was associated with the magnitude of ASD symptoms. These findings indicate that EI imbalance in ASD is neither globally distributed nor static, but expressed through regionally and developmentally specific differences, with relevance for ASD heterogeneity.

neuroscience↗

bioRxiv2025

Tentorium cerebelli notch severity in the human brain: protocol, distribution and histopathology validation

The dura forms an impression, the tentorial notch (TN), on the surface of the entorhinal cortex (EC). To characterize the potential injury to the EC, we evaluated the entorhinal surface in 55 postmortem samples. We developed a semi-quantitative protocol to rate the TN severity and evaluated the impact of the TN on the surrounding tissue. We rated the penumbral injury as: none, moderate or severe. We demonstrate that 96% of the samples showed a TN; specifically mild (33%), moderate (47%) and severe (16%). TN severity correlated positively with penumbra scores (Kendalls coefficient = 0.65, 95% CI [0.535, 0.735]). We found no association between TN severity levels and Braak and Braak stages (Fischers exact P value = .862). We established a robust protocol for assessing the tentorial notch, addressing a gap in understanding anatomical factors that may contribute to EC vulnerability in Alzheimers disease.

neuroscience↗