PriorDynamics | The neural dynamics of perceptual priors in audition

Summary
To maintain a coherent and continuous percept over time, the brain relies on past sensory information to predict forthcoming stimuli. Combining novel behavioural methods with advanced neuroimaging techniques, the present research project aims to determine the neural mechanisms by which the auditory system uses information from the recent past to overcome signal noise and ambiguity. Specifically, we test the hypothesis that sensory predictions involve neural oscillations at alpha rhythm, ~9-10 Hz, that mediate the propagation of perceptual priors. The first part of this research project investigates the neural structures underlying such predictive oscillatory mechanism. To this end, we adapt a novel time-resolved sampling technique used to examine rhythmic fluctuations in perceptual performance for functional magnetic resonance imaging (fMRI). We hypothesise that cortical and subcortical activation, especially in the auditory cortex and thalamus, will exhibit rhythmic modulations that correlate with oscillations in decision bias during the detection of a brief auditory signal masked by white noise. The second part of this project examines whether the resolution of perceptual ambiguities by prior contextual information involves similar oscillatory mechanisms. For this purpose, we combine the time-resolved sampling technique with a classic paradigm (involving Shepard tones) for inducing ambiguous pitch shifts. By presenting a single tone before the ambiguous stimulus, listeners can be biased toward a perceived upward or downward pitch shift. If resolving perceptual ambiguities involves oscillatory mechanisms, we expect to observe periodic fluctuations of decision bias (that is, the tendency to make certain responses) at alpha rhythm over time. The results of this research project will shed light on a potentially crucial and yet unknown core process of perception, useful in every interaction we have with the world.
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More information & hyperlinks
Web resources: https://cordis.europa.eu/project/id/101032112
Start date: 01-06-2022
End date: 31-05-2024
Total budget - Public funding: 190 734,72 Euro - 190 734,00 Euro
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Original description

To maintain a coherent and continuous percept over time, the brain relies on past sensory information to predict forthcoming stimuli. Combining novel behavioural methods with advanced neuroimaging techniques, the present research project aims to determine the neural mechanisms by which the auditory system uses information from the recent past to overcome signal noise and ambiguity. Specifically, we test the hypothesis that sensory predictions involve neural oscillations at alpha rhythm, ~9-10 Hz, that mediate the propagation of perceptual priors. The first part of this research project investigates the neural structures underlying such predictive oscillatory mechanism. To this end, we adapt a novel time-resolved sampling technique used to examine rhythmic fluctuations in perceptual performance for functional magnetic resonance imaging (fMRI). We hypothesise that cortical and subcortical activation, especially in the auditory cortex and thalamus, will exhibit rhythmic modulations that correlate with oscillations in decision bias during the detection of a brief auditory signal masked by white noise. The second part of this project examines whether the resolution of perceptual ambiguities by prior contextual information involves similar oscillatory mechanisms. For this purpose, we combine the time-resolved sampling technique with a classic paradigm (involving Shepard tones) for inducing ambiguous pitch shifts. By presenting a single tone before the ambiguous stimulus, listeners can be biased toward a perceived upward or downward pitch shift. If resolving perceptual ambiguities involves oscillatory mechanisms, we expect to observe periodic fluctuations of decision bias (that is, the tendency to make certain responses) at alpha rhythm over time. The results of this research project will shed light on a potentially crucial and yet unknown core process of perception, useful in every interaction we have with the world.

Status

SIGNED

Call topic

MSCA-IF-2020

Update Date

28-04-2024
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Horizon 2020
H2020-EU.1. EXCELLENT SCIENCE
H2020-EU.1.3. EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions (MSCA)
H2020-EU.1.3.2. Nurturing excellence by means of cross-border and cross-sector mobility
H2020-MSCA-IF-2020
MSCA-IF-2020 Individual Fellowships