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Levine, G.

Publications and source records attributed to Levine, G..

3 recordsLinked to original sources

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↗

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↗

Decreased auditory cortical activations and altered long-range alpha-band connectivity characterize passive auditory spatial attention in ASD

Autism Spectrum Disorder (ASD) is a developmental condition characterized by difficulties in social interaction, communication and sensory processing. The ability to orient towards sounds is a key component of social interactions, yet auditory spatial attention remains relatively understudied in ASD, despite prior research indicating differences in this domain. Here, we investigate the neural signatures associated with passive auditory spatial attention in children with ASD (n = 21, ages 6-17) relative to age- and IQ-matched typically developing (TD) children (n = 31), using source-localized magnetoencephalography (MEG). Participants listened passively, while watching a silenced movie, to non-social auditory stimuli designed to either remain lateralized to one hemifield (stay trials), or to change in location from one side to the contralateral hemifield (jump trials). Linear mixed effects modeling showed lower cortical activation in the auditory cortex in the ASD group in response to jump trials, relative to the TD group. Additionally, functional connectivity analyses showed higher alpha-band functional connectivity in the ASD group between left auditory cortex seeds and right prefrontal and left parietal regions known to be recruited during auditory spatial attention. Right prefrontal alpha-band connectivity estimates were associated with behaviorally assessed auditory processing scores, whereas left parietal connectivity estimates were associated with ASD symptomatology. Our results align with the hypothesis that auditory spatial attention generally, and specifically orientation to sounds even when experienced passively, differs in ASD individuals.

neuroscience↗