Claudine Jolle Gauthier1, 2, Ccile Madjar3, 4, Laurence Desjardins-Crpeau3, 5, Pierre Bellec3, 6, Louis Bherer, 37, Richard D. Hoge2
1Neurophysics, Max Planck Institute for Cognitive and Brain Sciences, Leipzig, Saxony, Germany; 2Physiology, CRIUGM/Universit de Montral, Montreal, Quebec, Canada; 3CRIUGM, Montreal, Quebec, Canada; 4Montreal Neurological Institute, Montreal, Quebec, Canada; 5Psychology, UQAM, Montreal, Quebec, Canada; 6Computer Science and Operations Research, Universit de Montral, Montreal, Quebec, Canada; 7Concordia University, Montreal, Quebec, Canada
The BOLD signal is often used as a direct index of neuronal activity to study changes with aging. However, profound changes in cerebrovascular properties in older adults may lead to biases in the interpretation of BOLD signal differences between young and old. Here we show that changes in baseline blood flow, reactivity to hypercapnia and calibration parameter M are present even in healthy aging. These changes may lead to underestimation of metabolic changes with aging.