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The speech-to-song transformation is an illusion in which certain spoken phrases are perceived as more song-like after being repeated several times. The present study addresses whether this perceptual transformation leads to a corresponding change in how accurately participants imitate pitch/time patterns in speech. We used illusion-inducing (illusion stimuli) and non-inducing (control stimuli) spoken phrases as stimuli. In each trial, one stimulus was presented eight times in succession. Participants were asked to reproduce the phrase and rate how music-like the phrase sounded after the first and final (eighth) repetitions. The ratings of illusion stimuli reflected more song-like perception after the final repetition than the first repetition, but the ratings of control stimuli did not change over repetitions. The results from imitative production mirrored the perceptual effects: pitch matching of illusion stimuli improved from the first to the final repetition, but pitch matching of control stimuli did not improve. These findings suggest a consistent pattern of speech-to-song transformation in both perception and production, suggesting that distinctions between music and language may be more malleable than originally thought both in perception and production., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This case series presents 2 Caucasian females that underwent orbital decompression surgery for symptomatic exophthalmos and postoperatively developed a change in their perception of pitch during vocal performance. One patient went as far as to undergo voice lessons in attempt to regain her pre-operative pitch perception; however, the attempt was unsuccessful. We propose the etiology of this complication is anatomic changes within the ethmoid sinus. Temporary changes in nasalance have previously been reported with functional endoscopic sinus surgery literature, but this specific complication of change in pitch perception has not., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Mismatch negativity (MMN) to pitch (pMMN) and to duration (dMMN) deviant stimuli is significantly more attenuated in long-term psychotic illness compared to first-episode psychosis (FEP). It was recently shown that source-modeling of magnetically recorded MMN increases the detection of left auditory cortex MMN deficits in FEP, and that computational circuit modeling of electrically recorded MMN also reveals left-hemisphere auditory cortex abnormalities. Computational modeling using dynamic causal modeling (DCM) can also be used to infer synaptic activity from EEG-based scalp recordings. We measured pMMN and dMMN with EEG from 26 FEP and 26 matched healthy controls (HCs) and used a DCM conductance-based neural mass model including α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid, N-methyl-D-Aspartate (NMDA), and Gamma-aminobutyric acid receptors to identify any changes in effective connectivity and receptor rate constants in FEP. We modeled MMN sources in bilateral A1, superior temporal gyrus, and inferior frontal gyrus (IFG). No model parameters distinguished groups for pMMN. For dMMN, reduced NMDA receptor activity in right IFG in FEP was detected. This finding is in line with literature of prefrontal NMDA receptor hypofunction in chronic schizophrenia and suggests impaired NMDA-induced synaptic plasticity may be present at psychosis onset where scalp dMMN is only moderately reduced. To the best of our knowledge, this is the first report of impaired NMDA receptor activity in FEP found through computational modeling of dMMN and shows the potential of DCM to non-invasively reveal synaptic-level abnormalities that underly subtle functional auditory processing deficits in early psychosis., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.