Open AccessCalibration of BOLD fMRI using breath holding reduces group variance during a cognitive task
Author(s) -
Thomason Moriah E.,
Foland Lara C.,
Glover Gary H.
Publication year - 2007
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.20241
Subject(s) - psychology , voxel , working memory , cognition , hum , elementary cognitive task , effects of sleep deprivation on cognitive performance , neuroscience , analysis of variance , audiology , brain mapping , confounding , medicine , radiology , art , performance art , art history
The proportionality of blood oxygen level‐dependent (BOLD) response during a cognitive task and that from a hypercapnic challenge was investigated in cortical structures involved in working memory (WM). Breath holding (BH) following inspiration was used to induce a BOLD response characteristic of regional vasomotor reactivity but devoid of metabolic changes. BOLD effects measured during BH were used to normalize individual subject activations during WM, which effectively reduced the confounding influence of individual‐ and region‐specific differences in hemodynamic responsivity common to both tasks. In a study of seven subjects, the BH calibration reduced intersubject variability in WM effect amplitude by 24.8% ( P < 0.03). Reduced intersubject variability resulted in a 23.7% increase in group WM activation voxel extent significant at P < 0.001, with further increases at more stringent thresholds. Because the BH task does not require CO 2 inhalation or other invasive manipulations and is broadly applicable across cortical regions, the proposed approach is simple to implement and may be beneficial for use not only in quantitative group fMRI analyses, but also for multicenter and longitudinal studies. Hum Brain Mapp, 2007. © 2006 Wiley‐Liss, Inc.