Data from: The music of silence. Part I: Responses to musical imagery encode melodic expectations and acoustics

Musical imagery is the voluntary internal hearing of music in the mind
without the need for physical action or external stimulation. Numerous
studies have already revealed brain areas activated during imagery.
However, it remains unclear to what extent imagined music responses
preserve the detailed temporal dynamics of the acoustic stimulus envelope
and, crucially, whether melodic expectations play any role in modulating
responses to imagined music, as they prominently do during listening.
These modulations are important as they reflect aspects of the human
musical experience, such as its acquisition, engagement, and enjoyment.
This study explored the nature of these modulations in imagined music
based on EEG recordings from 21 professional musicians (6 females and 15
males). Regression analyses were conducted to demonstrate that imagined
neural signals can be predicted accurately, similarly to the listening
task, and were sufficiently robust to allow for accurate identification of
the imagined musical piece from the EEG. In doing so, our results indicate
that imagery and listening tasks elicited an overlapping but distinctive
topography of neural responses to sound acoustics, which is in line with
previous fMRI literature. Melodic expectation, however, evoked very
similar frontal spatial activation in both conditions, suggesting that
they are supported by the same underlying mechanisms. Finally, neural
responses induced by imagery exhibited a specific transformation from the
listening condition, which primarily included a relative delay and a
polarity inversion of the response. This transformation demonstrates the
top-down predictive nature of the expectation mechanisms arising during
both listening and imagery.