Leske Sabine, Endestad Tor, Volehaugen Vegard, Foldal Maja D, Blenkmann Alejandro O, Solbakk Anne-Kristin, Danielsen Anne
RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Forskningsveien 3A, Oslo, 0373, Norway.
Department of Musicology, University of Oslo, Oslo, Norway.
Sci Rep. 2025 Jan 28;15(1):3510. doi: 10.1038/s41598-025-86895-y.
Periodic sensory inputs entrain oscillatory brain activity, reflecting a neural mechanism that might be fundamental to temporal prediction and perception. Most environmental rhythms and patterns in human behavior, such as walking, dancing, and speech do not, however, display strict isochrony but are instead quasi-periodic. Research has shown that neural tracking of speech is driven by modulations of the amplitude envelope, especially via sharp acoustic edges, which serve as prominent temporal landmarks. In the same vein, research on rhythm processing in music supports the notion that perceptual timing precision varies systematically with the sharpness of acoustic onset edges, conceptualized in the beat bin hypothesis. Increased envelope sharpness induces increased precision in localizing a sound in time. Despite this tight relationship between envelope shape and temporal processing, it is currently unknown how the brain uses predictive information about envelope features to optimize temporal perception. With the current EEG study, we show that the predicted sharpness of the amplitude envelope is encoded by pre-target neural activity in the beta band (15-25 Hz), and has an impact on the temporal perception of target sounds. We used probabilistic sound cues in a timing judgment task to inform participants about the sharpness of the amplitude envelope of an upcoming target sound embedded in a beat sequence. The predictive information about the envelope shape modulated task performance and pre-target beta power. Interestingly, these conditional beta-power modulations correlated positively with behavioral performance in the timing judgment task and with perceptual temporal precision in a click-alignment task. This study provides new insight into the neural processes underlying prediction of the sharpness of the amplitude envelope during beat perception, which modulate the temporal perception of sounds. This finding could reflect a process that is involved in temporal prediction, exerting top-down control on neural entrainment via the prediction of acoustic edges in the auditory stream.
周期性的感觉输入会引发振荡性脑活动，这反映了一种可能是时间预测和感知基础的神经机制。然而，人类行为中的大多数环境节律和模式，如行走、跳舞和言语，并非严格等时的，而是准周期性的。研究表明，语音的神经追踪是由振幅包络的调制驱动的，尤其是通过尖锐的声学边缘，这些边缘作为突出的时间地标。同样，音乐节奏处理的研究支持这样一种观点，即感知定时精度会随着声学起始边缘的锐度而系统地变化，这在节拍仓假设中有所概念化。包络锐度的增加会导致在时间上定位声音的精度提高。尽管包络形状与时间处理之间存在这种紧密关系，但目前尚不清楚大脑如何利用关于包络特征的预测信息来优化时间感知。通过当前的脑电图研究，我们表明，振幅包络的预测锐度由β波段（15 - 25赫兹）的目标前神经活动编码，并对目标声音的时间感知产生影响。我们在定时判断任务中使用概率性声音线索，让参与者了解嵌入节拍序列中的即将到来的目标声音的振幅包络的锐度。关于包络形状的预测信息调制了任务表现和目标前β功率。有趣的是，这些条件性β功率调制与定时判断任务中的行为表现以及点击对齐任务中的感知时间精度呈正相关。这项研究为节拍感知期间振幅包络锐度预测背后的神经过程提供了新的见解，这些过程调节声音的时间感知。这一发现可能反映了一个参与时间预测的过程，通过预测听觉流中的声学边缘对神经同步进行自上而下的控制。
