Each movie is generated by starting with a .wav file of the piece of music. The audio waveform is then digitally processed in a series of steps that model neural responses in the auditory periphery, extract periodicity pitch, and finally project the time-varying periodicity pitch distributions to the surface of a torus. The toroidal surface represents tonal space that is encountered in Western tonal music. The letters on the image in the movies correspond to the 24 major (uppercase letters) and minor (lowercase letters) keys. As the harmonies in the music change, so does the activation pattern on the toroidal surface.For a somewhat more detailed description, click here.
See also, Janata et al. (2002) The cortical topography of tonal structures underlying western music. Science, 298:2167-2170
All images/movies copyright © 2005 Petr Janata