Biology subjects

Volehaugen, V.

Publications and source records attributed to Volehaugen, V..

3 recordsLinked to original sources

bioRxiv2023

Predicting the Beat Bin - Beta Oscillations Support Top-Down Prediction of the Temporal Precision of a Rhythmic Event

Periodic sensory inputs entrain oscillatory brain activity, reflecting a neural mechanism that might be fundamental to temporal prediction and perception. Most environmental rhythms, such as music or speech, however, are rather 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 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 sounds. Using probabilistic sound cues in an EEG experiment, we informed participants about the sharpness of the amplitude envelope of an upcoming target sound embedded in a quasi-isochronous beat. The predictive information about the envelope shape modulated the performance in the timing judgment task 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.

neuroscience↗

bioRxiv2019

Glutamatergic modulation of auditory cortex connectivity with attentional brain networks in unpredictable perceptual environment

In a stable environment the brain can minimize processing required for sensory input by forming a predictive model of the surrounding world and suppressing neural response to predicted stimuli. Unpredicted stimuli lead to a prediction error signal propagation through the perceptual network, and resulting adjustment to the predictive model. The inter-regional plasticity which enables the model-building and model-adjustment is hypothesized to be mediated via glutamatergic receptors. While pharmacological challenge studies with glutamate receptor ligands have demonstrated impact on prediction-error indices, it is not clear how inter-individual differences in the glutamate system affect the prediction-error processing in non-medicated state. In the present study we examined 20 healthy young subjects with resting-state proton MRS spectroscopy to characterize glutamate+glutamine (rs-Glx) levels in their Heschls gyrus (HG), and related this to HG functional connectivity during a roving auditory oddball protocol. No rs-Glx effects were found within the frontotemporal prediction-error network. Larger rs-Glx signal was related to stronger connectivity between HG and bilateral inferior parietal lobule during unpredictable auditory stimulation. We also found effects of rs-Glx on the coherence of default mode network (DMN) and frontoparietal network (FPN) during unpredictable auditory stimulation. Our results demonstrate the importance of Glx in modulating long-range connections and wider networks in the brain during perceptual inference.

neuroscience↗

bioRxiv2018

Hierarchical modulation of auditory prediction error signaling is independent of attention

The auditory system is tuned to detect rhythmic regularities or irregularities in the environment which can occur on different timescales, i.e. regularities in short (local) and long (global) timescale which could conflict or converge. While MMN and P3b are thought to index local and global deviance, respectively, it is not clear how these hierarchical levels interact and to what extent attention modulates this interaction. We used a hierarchical oddball paradigm with local (sequence-level) and global (block-level) violations of regularities in 5-tone sequences, in attended and unattended conditions. Amplitude of negativity in the N2 timeframe and positivity in the P3b timeframe elicited by the final tone in the sequence were analyzed in a 2*2*2 factorial model (local status, global status, attention condition). We found a significant interaction between the local and global status of the final tone on the N2 amplitude (p<.001, {eta}p2= .55), while there was no significant three-way interaction with attention (p > .05), together demonstrating that lower-level prediction error is modulated by detection of higher-order regularity but expressed independently of attention. Regarding P3b amplitude, we found significant main effect of global status (p<.001, {eta}p2= .42), and an interaction between global status and attention (p < .001, {eta}p2= .70). Thus, higher-level prediction error, indexed by P3b, is sensitive to global regularity violations if the auditory stream is attended. The results demonstrate the capacity of our auditory perception to rapidly resolve conflicts between different levels of predictive hierarchy as indexed by MMN modulation, while P3b represents a different, attention-dependent system.

neuroscience↗