Biology subjects

Spierings, M.

Publications and source records attributed to Spierings, M..

6 recordsLinked to original sources

bioRxiv2025

Arousal-related mediation of perceptual belief updating across auditory domains

Belief updating refers to the integration of prior beliefs with incoming evidence and guides decision-making under uncertainty. In response to surprising events, this process is thought to be modulated by the locus-coeruleus-noradrenaline (LC-NA) arousal system, observable via pupil dilations (PDs). Pertinent literature has mostly focused on conscious, high-level decision-making and estimation processes, while assuming that the same principles apply to low-level sensory perceptual decision-making and generalize across tasks, domains and modalities. To address some of these assumptions, we devised a novel perceptual discrimination paradigm, investigating behavior and PDs across auditory domains. Participants were presented with auditory sequences of randomized length at a rapid pace, changing intermittently between two latent states: acceleration vs. deceleration (temporal group, N = 25) and clockwise vs. counterclockwise movement (spatial group, N = 22). Under high uncertainty, participants continuously inferred latent states to report the final state per sequence. To extract per-stimulus estimates of PDs during sequences, we fitted a deconvolution-based general linear model to the continuous pupil traces with a free amplitude parameter reflecting ongoing PDs. A Bayesian observer model was fitted to participants responses and used to estimate information gain and surprisal for every stimulus. Participants performance and PDs showed strong sensitivity to the occurrence of change-points. Both computational variables significantly predicted PDs in both domains, with information gain outperforming surprisal in a model comparison. Further model comparison revealed significant preference for models excluding possible domain-specific effects over models including them, pointing towards a constant effect over domains. We conclude that behavior and associated PDs observed in our purely perceptual auditory task align with Bayesian principles of belief updating. The observed lack of domain specificity supports the assumed generalizability of belief updating.

neuroscience↗

bioRxiv2025

Visual Attention Dynamics Entrain to an Auditory Beat:The Palimpsest Paradigm

We investigated how rhythmic auditory cues influence visual perception of dynamically presented, partially masked words. Participants were presented with an ever-changing array of multiple overlapping, semi-transparent five-letter words, in a stimulus we dubbed a "palimpsest". These letter arrays mostly consisted of nonsense strings, but every two seconds, two actual words briefly appeared consecutively (and typically subliminally), superimposed upon the nonsense letter array. Participants were asked to name all words that they recognized. One group of participants observed only visual stimuli, while a second group additionally received an acoustic stimulus: a drum beat that was timed to co-occur with some, but not all, of the words in the array. Participants provided with this additional synchronized auditory information were able to detect more words from the array, and the words that they recognized were typically those that coincided with the dominant acoustic beat. This shows that when visually presented words are difficult to detect, acoustic cues can improve word recognition by dynamically focusing participants attention upon specific moments in time. We also found that the auditory rhythm continued to affect visual perception after the sound fade fades away. A third group heard the drum beat only for the first four seconds, after which it faded away for the remaining 76 seconds of a trial. Like the continuous beat in condition two, the transient acoustic rhythm continued to influence participants perception of the written words, even after its cessation. These results are consistent with the hypothesis that dynamic, temporal aspects of visual perception can be strongly influenced by periodic auditory input, and that this results from the entrainment of an endogenous multi-modal attentive process. The implications for neural models of dynamic attention are discussed.

evolutionary biology↗

bioRxiv2024

Context-dependent Rhythmicity in Chimpanzee Displays

Rhythm is an important component of human language and music production. Rhythms like isochrony (intervals spaced equally in time), are also present in vocalisations of certain non-human species, including several birds and mammals. This study aimed to identify rhythmic patterns with music-based methods within display behaviour of chimpanzees (Pan troglodytes), humans closest living relatives. Behavioural observations were conducted on individuals from two zoo-housed colonies. We found isochronous rhythms in vocal (e.g. pants, grunts and hoots), as well as in motoric (e.g. swaying and stomping) behavioural sequences. Among individuals, variation was found in the duration between onsets of behavioural elements, resulting in individual-specific tempi. Despite this variation in individual tempi, display sequences were consistently structured with stable, isochronous rhythms. Overall, directed displays, targeted at specific individuals, were less isochronous than undirected displays. The presence of rhythmic patterns across two independent colonies of chimpanzees, suggests that underlying mechanisms for rhythm production may be shared between humans and non-human primates. This shared mechanism indicates that the cognitive requirements for rhythm production potentially preceded human music and language evolution.

animal behavior and cognition↗

bioRxiv2024

The consonance of chords: The effect of subsemitone changes to each of the notes in a trichord on its perceived consonance

Consonance plays a key role in how listeners experience music, but the factors influencing consonance perception remain a topic of discussion, for instance regarding the role of the familiarity of note combinations. Previous empirical studies of consonance have used common, familiar chords, making it harder to separate the effect of acoustic features from familiarity. Here we explored consonance perception in an unfamiliar, non-standardly tuned 0-5-10 trichord. A test was conducted in which 100 musicians and 100 nonmusicians compared the consonance of an original, non-standard, 0-5-10 chord and an adapted version, in which the lowest, middle or upper note was raised or lowered with 25 or 50 cents. According to a model based on continuous acoustic features, any adaptation to a 0-5-10 chord should yield a comparable decrease in consonance. We indeed found a general consonance decrease, but this was stronger for adaptations enlarging the distance between the lowest and the upper note, i.e. lowering the lowest or raising the highest note, than for other adaptations. These results deviate from the models predictions and from patterns observed in standard, more familiar chords. Future research should examine the generalizability of these findings to other chords than the 0-5-10 trichord.

animal behavior and cognition↗

bioRxiv2024

Adult male Lar gibbon sings the female great-call: A case study of inter-sex song production in a non-human primate

Gibbons are known as one of the most vocal non-human primates. They vocally advertise and reinforce their pair-bonds by singing complex duets, in which both the male and female perform a predetermined sex-specific set of song phrases, including the loud and elongated great-calls. Only females and sub-adult male gibbons have been previously observed performing great-calls. Once a male gibbon matures, he normally stops great-call production completely but continues singing other and less high-pitched song phrases. This case study describes a fully adult, castrated male lar gibbon (Hylobates lar, 32 years old, zoo-housed) who performs both male phrases of the duet, including the female great-call. The male regularly produced great-calls despite being in a, relatively weak, pair bond with a female conspecific. His great-calls adhered to the general structure of typical female great-calls but were shorter and had a lower maximum frequency. Notably, he produced these great-calls predominantly when the female was absent, especially when she was in their inside enclosure whilst he was outside. Behavioural observations indicate that the occurrence of great-calls by the male cannot be predicted based on pre-song behaviour or his interaction with the female. The recurrence of sub-adult singing behaviour in a fully grown adult is most likely due to his reduced testosterone levels. This study sheds light on the intricate dynamics of duetting and the unique occurrence of cross-sex song production in gibbons, emphasizing the complexity of pair-bond communication in this species.

animal behavior and cognition↗

bioRxiv2024

Bayesian Prior Uncertainty and Surprisal Elicit Distinct Neural Patterns During Sound Localization in Dynamic Environments

Estimating the location of a stimulus is a key function in sensory processing, and widely considered to result from the integration of prior information and sensory input according to Bayesian principles. A deviation of sensory input from the prior elicits surprisal, depending on the uncertainty of the prior. While this mechanism is increasingly understood in the visual domain, much less is known about its implementation in audition, especially regarding spatial localization. Here, we combined human EEG with computational modeling to study auditory spatial inference in a noisy, volatile environment and analyzed behavioral and neural patterns associated with prior uncertainty and surprisal. First, our results demonstrate that participants indeed used prior information during periods of stable environmental statistics, but showed evidence of surprisal and discarded prior information following environmental changes. Second, we observed distinct EEG activity patterns associated with prior uncertainty and surprisal in both the time- and time-frequency domain, which are in line with previous studies using visual tasks. Third, these EEG activity patterns were predictive of our participants sound localization error, response uncertainty, and prior bias on a trial-by-trial basis. In summary, our work provides novel behavioral and neural evidence for Bayesian inference during dynamic auditory localization.

neuroscience↗