Brain Imaging of Different Music Sound Duration as Revealed by Standardized Low Resolution Brain Electromagnetic Tomography (sLORETA)

Mismatch negativity (MMN) was used to investigate the processing of different synthesized music sounds duration in the human auditory perception. Compared to the short sound, the long sound elicited a more prominent MMN occurring later than that of the short one. sLORETA computation of the mismatch responses yielded clear left-hemispheric laterality in both types of sound duration. However, the short sound produced MMN maximum over the middle temporal gyrus (MTG), whereas maximum of the MMN activated by the long sound was observed over the superior temporal gyrus (STG). The results suggest the existence of the long-term memory trace, and housed primarily in the left hemisphere as revealed by sLORETA. Additionally, the spatial and temporal features of the long sound indicate delayed activation of left-lateralized perisylvian cell assemblies that function as cortical memory traces of long music sound in the human auditory cortex.