A Self Organized Map Method to Classify Auditory-Color Synesthesia from Frontal Lobe Brain Blood Volume
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 32797
A Self Organized Map Method to Classify Auditory-Color Synesthesia from Frontal Lobe Brain Blood Volume

Authors: Takashi Kaburagi, Takamasa Komura, Yosuke Kurihara


Absolute pitch is the ability to identify a musical note without a reference tone. Training for absolute pitch often occurs in preschool education. It is necessary to clarify how well the trainee can make use of synesthesia in order to evaluate the effect of the training. To the best of our knowledge, there are no existing methods for objectively confirming whether the subject is using synesthesia. Therefore, in this study, we present a method to distinguish the use of color-auditory synesthesia from the separate use of color and audition during absolute pitch training. This method measures blood volume in the prefrontal cortex using functional Near-infrared spectroscopy (fNIRS) and assumes that the cognitive step has two parts, a non-linear step and a linear step. For the linear step, we assume a second order ordinary differential equation. For the non-linear part, it is extremely difficult, if not impossible, to create an inverse filter of such a complex system as the brain. Therefore, we apply a method based on a self-organizing map (SOM) and are guided by the available data. The presented method was tested using 15 subjects, and the estimation accuracy is reported.

Keywords: Absolute pitch, functional near-infrared spectroscopy, prefrontal cortex, synesthesia.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1129602

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 931


[1] Miyazaki Kenichi: “How well do we understand absolute pitch?”, Acoustical Science and Technology Vol. 25, No. 6, pp. 270-282 (2004).
[2] L.L. Cuddy: “Practice effects in the absolute judgment of pitch”, Journal of the Acoustical Society of America, Vol. 43, No. 5, pp.1069-1076 (1968).
[3] L.L. Cuddy: “Training the absolute identification of pitch”, Perception & Psychophysics, Vol. 8, No. 5, pp.265-269 (1970).
[4] P. K. Gregersen, E. Kowalsky, A. Lee, S. Baron-Cohen, S.E. Fisher, J. E. Asher, D. Ballard, J. Freudenberg, W. Li: "Absolute pitch exhibits phenotypic and genetic overlap with synesthesia”, Human Molecular Genetics, Vol. 22, No. 10, pp. 2097-104 (2013).
[5] A. Sakakibara “Why are people able to acquire absolute pitch only during early childhood?: Training age and acquisition of absolute pitch”, Japanese Journal of Educational Psychology, Vol. 52, No4, pp. 485-496 (2004).