Oderbolz, C. | Search bioRxiv

bioRxiv2024

Concurrent processing of the prosodic hierarchy is supported by cortical entrainment and phase-amplitude coupling

Models of phonology posit a hierarchy of prosodic units that are relatively independent from syntactic structure, requiring its own parsing. Surprisingly, it remains unexplored how this prosodic hierarchy is represented in the brain. We investigated this foundational question by means of an EEG study. Thirty young adults listened to German sentences containing manipulations at different levels of the prosodic hierarchy. Evaluating speech-to-brain cortical entrainment and phase-amplitude coupling revealed that prosodys hierarchical structure is maintained at the neural level. The faithfulness of this tracking varied as a function of the hierarchys degree of intactness as well as systematic inter-individual differences in audio-motor synchronization. The results underscore the role of complex oscillatory mechanisms in configuring the continuous and hierarchical nature of the speech signal and firmly situate prosody as a structure indispensable from theoretical perspectives on spoken language comprehension in the brain.

neuroscience↗

bioRxiv2018

A reevaluation of the electrophysiological correlates of absolute pitch and relative pitch: No evidence for an absolute pitch-specific negativity.

Musicians with absolute pitch effortlessly identify the pitch of a sound without an external reference. Previous neuroscientific studies on absolute pitch have typically had small samples sizes and low statistical power, making them susceptible for false positive findings. In a seminal study, Itoh et al. (2005) reported the elicitation of an absolute pitch-specific event-related potential component during tone listening -- the AP negativity. Additionally, they identified several components as correlates of relative pitch, the ability to identify relations between pitches. Here, we attempted to replicate the main findings of Itoh et al.s study in a large sample of musicians (n = 104) using both frequentist and Bayesian inference. We were not able to replicate the presence of an AP negativity during tone listening in individuals with high levels of absolute pitch, but we partially replicated the findings concerning the correlates of relative pitch. Our results are consistent with several previous studies reporting an absence of differences between musicians with and without absolute pitch in early auditory evoked potential components. We conclude that replication studies form a crucial part in assessing extraordinary findings, even more so in small fields where a single finding can have a large impact on further research.

neuroscience↗