Ccile Madjar1, Claudine Jolle Gauthier1,2, Rasmus M. Birn3, Rick D. Hoge1,2
1CRIUGM/UNF, Montral, Qubec, Canada; 2Physiology/Biomedical Engineering, University of Montral, Montral, Qubec, Canada; 3University of Wisconsin, Madison, WI, United States
With the ever-increasing number of studies investigating the default-mode network (DMN), there has been a growing interest in trying to take into account the confounding effects from physiological noise, such as respiration, while performing connectivity analysis of fMRI. Variations in respiration cause fluctuations in end-tidal CO2 (ETCO2) which have been shown to exert a significant effect on BOLD fMRI signal. Here we present data comparing resting-state correlations in the DMN, as well as task-related activations, between two conditions: 1) while tightly controlling for ETCO2 concentrations, and 2) while ETCO2 values were allowed to vary spontaneously.