Open AccessImaging subcortical auditory activity in humans
Author(s) -
Guimaraes A.R.,
Melcher J.R.,
Talavage T.M.,
Baker J.R.,
Ledden P.,
Rosen B.R.,
Kiang N.Y.S.,
Fullerton B.C.,
Weisskoff R.M.
Publication year - 1998
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/(sici)1097-0193(1998)6:1<33::aid-hbm3>3.0.co;2-m
Subject(s) - neuroscience , auditory cortex , inferior colliculi , functional magnetic resonance imaging , psychology , brain activity and meditation , human brain , cortex (anatomy) , brain mapping , superior colliculi , auditory perception , inferior colliculus , visual cortex , electroencephalography , perception , visual system , nucleus
There is a lack of physiological data pertaining to how listening humans process auditory information. Functional magnetic resonance imaging (fMRI) has provided some data for the auditory cortex in awake humans, but there is still a paucity of comparable data for subcortical auditory areas where the early stages of processing take place, as amply demonstrated by single‐unit studies in animals. It is unclear why fMRI has been unsuccessful in imaging auditory brain‐stem activity, but one problem may be cardiac‐related, pulsatile brain‐stem motion. To examine this, a method eliminating such motion (using cardiac gating) was applied to map sound‐related activity in the auditory cortices and inferior colliculi in the brain stem. Activation in both the colliculi and cortex became more discernible when gating was used. In contrast with the cortex, the improvement in the colliculi resulted from a reduction in signal variability, rather than from an increase in percent signal change. This reduction is consistent with the hypothesis that motion or pulsatile flow is a major factor in brain‐stem imaging. The way now seems clear to studying activity throughout the human auditory pathway in listening humans. Hum. Brain Mapping 6:33–41, 1998. © 1998 Wiley‐Liss, Inc.