Most task-based functional MRI analyses assume something approaching a "standard" or "canonical" hemodynamic response function (HRF). But how consistent is the hemodynamic response really? Does it change in aging? We'll have an informal discussion of two early and influential articles on the topic:

Aguirre GK, Zarahn E, D'Esposito M (1998) The variability of human, BOLD hemodynamic responses. NeuroImage 8:360-369. http://cl.ly/aMmI

D'Esposito M, Zarahn E, Aguirre GK, Rypma B (1999) The effect of normal aging on the coupling of neural activity to the bold hemodynamic response. NeuroImage 10:6-14. http://cl.ly/aLpx