Open AccessHuman brain activation during passive listening to sounds from different locations: An fMRI and MEG study
Author(s) -
Brunetti M.,
Belardinelli P.,
Caulo M.,
Del Gratta C.,
Della Penna S.,
Ferretti A.,
Lucci G.,
Moretti A.,
Pizzella V.,
Tartaro A.,
Torquati K.,
Olivetti Belardinelli M.,
Romani G.L.
Publication year - 2005
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.20164
Subject(s) - supramarginal gyrus , neuroscience , superior temporal gyrus , magnetoencephalography , gyrus , psychology , lateralization of brain function , auditory cortex , parietal lobe , inferior parietal lobule , temporal lobe , functional magnetic resonance imaging , superior frontal gyrus , stimulus (psychology) , human brain , middle temporal gyrus , inferior frontal gyrus , electroencephalography , cognitive psychology , epilepsy
Abstract Recent animal and human studies indicate the existence of a neural pathway for sound localization, which is similar to the “where” pathway of the visual system and distinct from the sound identification pathway. This study sought to highlight this pathway using a passive listening protocol. We employed fMRI to study cortical areas, activated during the processing of sounds coming from different locations, and MEG to disclose the temporal dynamics of these areas. In addition, the hypothesis of different activation levels in the right and in the left hemispheres, due to hemispheric specialization of the human brain, was investigated. The fMRI results indicate that the processing of sound, coming from different locations, activates a complex neuronal circuit, similar to the sound localization system described in monkeys known as the auditory “where” pathway. This system includes Heschl's gyrus, the superior temporal gyrus, the supramarginal gyrus, and the inferior and middle frontal lobe. The MEG analysis allowed assessment of the timing of this circuit: the activation of Heschl's gyrus was observed 139 ms after the auditory stimulus, the peak latency of the source located in the superior temporal gyrus was at 156 ms, and the inferior parietal lobule and the supramarginal gyrus peaked at 162 ms. Both hemispheres were found to be involved in the processing of sounds coming from different locations, but a stronger activation was observed in the right hemisphere. Hum. Brain Mapping, 2005. © 2005 Wiley‐Liss, Inc.