In the summer of 2019, I was lucky to be invited to be part of a Lorentz workshop, in which an inspiring group of researchers came together to discuss rhythm from every possible angle. This workshop was instigated by a fabulous organising team:Henkjan Honing, Sonja Kotz, Andrea Ravignani, and Michael Greenfield. The results of all the fruitful discussions will be published soon in a Special Issue in Philosophical Transactions B, including a paper co-authored by me on how to test rhythmic abilities in human and non-human animals.

In the paper, co-authored by Carel ten Cate, Vivek Nityananda, and Andrew Rouse, we discuss how different paradigms are used in different species. For example, birds are often tested on their rhythm perception, while monkeys are often tested on rhythm production, making it very hard to compare their abilities. The paper is now available as a preprint on PsyArxiv!

Bouwer, F.L., Honing, H., & Slagter, H.A. (2020). Beat-based and Memory-based Temporal Expectations in Rhythm: Similar Perceptual Effects, Different Underlying Mechanisms

All data, experimental files, and analysis scripts are available here. An open access pre-print of the paper, which is identical in content, is available here. The publishers version can be found here.

Predicting the timing of incoming information allows the brain to optimize information processing in dynamic environments. Behaviorally, temporal expectations have been shown to facilitate processing of events at expected time points, such as sounds that coincide with the beat in musical rhythm. Yet, temporal expectations can develop based on different forms of structure in the environment, not just the regularity afforded by a musical beat. Little is still known about how different types of temporal expectations are neurally implemented and affect performance. Here, we orthogonally manipulated the periodicity and predictability of rhythmic sequences to examine the mechanisms underlying beat-based and memory-based temporal expectations, respectively. Behaviorally and using EEG, we looked at the effects of beat-based and memory-based expectations on auditory processing when rhythms were task-relevant or task-irrelevant. At expected time points, both beat-based and memory-based expectations facilitated target detection and led to attenuation of P1 and N1 responses, even when expectations were task-irrelevant (unattended). For beat-based expectations, we additionally found reduced target detection and enhanced N1 responses for events at unexpected time points (e.g., off-beat), regardless of the presence of memory-based expectations or task relevance. This latter finding supports the notion that periodicity selectively induces rhythmic fluctuations in neural excitability and furthermore indicates that, although beat-based and memory-based expectations may similarly affect auditory processing of expected events, their underlying neural mechanisms may be different.

F.L. Bouwer, H. Honing, & H.A. Slagter (2019). Beat-based and memory-based temporal expectations in rhythm: similar perceptual effects, different underlying mechanisms

Predicting the timing of incoming information allows the brain to optimize information processing in dynamic environments. Behaviorally, temporal expectations have been shown to facilitate processing of events at expected time points, such as sounds that coincide with the beat in musical rhythm. Yet, temporal expectations can develop based on different forms of structure in the environment, not just the regularity afforded by a musical beat. Little is still known about how different types of temporal expectations are neurally implemented and affect performance. Here, we orthogonally manipulated the periodicity and predictability of rhythmic sequences to examine the mechanisms underlying beat-based and memory-based temporal expectations, respectively.

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