Finnish and Danish
researchers have developed a new method that performs brain decoding during
continuous listening to real music. Based on recorded brain responses, the
method predicts how certain features related to tone color and rhythm of the
music change over time, and recognizes which piece of music is being listened
to. The method also allows pinpointing the areas in the brain that are most
crucial for the processing of music. The study was recently published in the
journal NeuroImage (Toiviainen P et al. Capturing the musical brain with
Lasso: Dynamic decoding of musical features from fMRI data. Neuroimage. 2013.
S1053-8119).
Using
functional magnetic resonance imaging (fMRI), the research team at the Finnish
Centre of Excellence in Interdisciplinary Music Research in the Universities of
Jyväskylä and Helsinki, and the Center for Functionally Integrative
Neuroscience in Aarhus University, Denmark, recorded the brain responses of
participants while they were listening to a 16-minute excerpt of the album
Abbey Road by the Beatles. Following this, they used computational algorithms
to extract a collection of musical features from the musical recording. Subsequently,
they employed a collection of machine-learning methods to train a computer
model that predicts how the features of the music change over time. Finally,
they develop a classifier that predicts which part of the music the participant
was listening to at each time. The researchers found that most of the musical
features included in the study could be reliably predicted from the brain data
and also found that the piece being listened to could be predicted
significantly better than chance. Fairly large differences were however found
between participants in terms of the prediction accuracy. An interesting
finding was that areas outside of the auditory cortex, including motor, limbic,
and frontal areas, had to be included in the models to obtain reliable predictions,
providing thus evidence for the important role of these areas in the processing
of musical features.
“We believe that decoding
provides a method that complements other existing methods to obtain more
reliable information about the complex processing of music in the brain”, says
Prof. Petri Toiviainen from the University of Jyväskylä. “Our results provide
additional evidence for the important involvement of emotional and motor areas
in music processing.”
http://tinyurl.com/Toiviainen-paper