![]() Starting from this evidence, which only at the surface represents a limit, I develop a preliminary proposal where discretization and phonological abstraction are the result of a continuous process that converts spectro-temporal (acoustic) states into neurophysiological states such that some properties of the former undergo changes interacting with the latter until a new equilibrium is reached. The available data do not permit us to clearly disambiguate between neural evidence suggesting pure acoustic patterns and those indicating abstract phonological features. After describing principal techniques and methods, I critically discuss magnetoencephalographic and electroencephalographic findings of speech processing based on event-related potentials and event-related oscillatory rhythms. This classical issue is discussed in the light of recent neurophysiological data which – thanks to direct measurements of temporal and spatial brain activation – provide new avenues to investigate the biological substrate of human language. In this work, I address the connection of phonetic structure with phonological representations. Our results are consistent with a precision modulation of auditory prediction error in a musical context, and suggest that this effect is specific to features that depend on the manipulated dimension-pitch information, in this case. Furthermore, in a separate behavioral experiment investigating the detection of pitch deviants, similar decreases were found for accuracy measures in response to more fine-grained increases in pitch entropy. No significant differences were found for intensity and timbre MMNm amplitudes. ![]() We found a reduction in pitch and slide MMNm amplitudes in the high-entropy as compared to the low-entropy context. ![]() Pitch entropy was quantitatively assessed with an information-theoretic model of auditory expectation. We compared high-entropy stimuli, consisting of a set of non-repetitive melodies, with low-entropy stimuli consisting of a simple, repetitive pitch pattern. Pitch, slide, intensity and timbre deviants were included. Magnetoencephalography was used to measure the magnetic counterpart of the mismatch negativity (MMNm) as a neural marker of prediction error in a multi-feature paradigm. We created musical tone sequences with different degrees of pitch uncertainty to manipulate the precision of participants’ auditory expectations. Here, we examined how prediction error responses behave in a more complex and ecologically valid auditory context than those typically studied. While there is some evidence for this phenomenon in the visual and, to a lesser extent, the auditory modality, little is known about whether it operates in the complex auditory contexts of daily life. Theories of predictive processing propose that prediction error responses are modulated by the certainty of the predictive model or precision.
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