Content area
Full Text
Accepted: 7 April 2021 / Published online: 7 June 2021
© The Author(s) 2021
Abstract
Decoding the rich temporal dynamics of complex sounds such as speech is constrained by the underlying neuronal-processing mechanisms. Oscillatory theories suggest the existence of one optimal perceptual performance regime at auditory stimulation rates in the delta to theta range (< 10 Hz), but reduced performance in the alpha range (10-14 Hz) is controversial. Additionally, the widely discussed motor system contribution to timing remains unclear. We measured rate discrimination thresholds between 4 and 15 Hz, and auditory-motor coupling strength was estimated through a behavioral auditory-motor synchronization task. In a Bayesian model comparison, high auditory-motor synchronizers showed a larger range of constant optimal temporal judgments than low synchronizers, with performance decreasing in the alpha range. This evidence for optimal processing in the theta range is consistent with preferred oscillatory regimes in auditory cortex that compartmentalize stimulus encoding and processing. The findings suggest, remarkably, that increased auditory-motor synchronization might extend such an optimal range towards faster rates.
Keywords Auditory . Perceptual constraints . Temporal sensitivity . Auditory-motor synchronization
(ProQuest: ... denotes formulae omitted.)
Introduction
Natural sounds such as speech or music contain temporal structure at multiple time scales. Particularly slow acoustic modulations in the delta-theta range (2-9 Hz) are considered crucial for speech and music processing (Ding et al., 2017; Pellegrino et al., 2011; Singh & Theunissen, 2003). Such natural statistics are arguably not accidental and co-occur with potential neuronal coding principles in auditory cortex (Ravignani et al., 2019; Singh & Theunissen, 2003). Support for this proposal comes from electrophysiological studies that identified endogenous oscillations in auditory cortex in the delta-theta band (Giraud et al., 2007; Keitel & Gross, 2016; Lakatos et al., 2005; Lubinus et al., 2019). By entraining to acoustic signals at these time scales, neuronal oscillations in auditory cortex might contribute to the processing of temporal information in sound (Ghitza, 2012; Giraud & Poeppel, 2012; Gross et al., 2013; McAuley & Jones, 2003; Miller & McAuley, 2005; Rimmele, Gross, et al., 2018). The optimal processing range of neuronal populations should, therefore, constrain auditory perception by facilitating auditory temporal processing within this range (Haegens & Zion Golumbic, 2018; Rimmele, Morillon, etal., 2018).
Perceptual constraints, such as decreased neuronal tracking of...