Comment on “The physiology of developmental changes in BOLD functional imaging signals” by Harris, Reynell, and Attwell

Accurate measurement of the variable of interest is critcal to successful science. Hemodynamic measurements f the blood oxygen level dependent (BOLD) fMRI signal re continually improving in human fMRI studies. As we rogress, it is imperative to re-examine previous assumpions as measurement techniques advance and as more nformation about lurking variables is learned. Harris, Reynell, and Attwell, in a Developmental Cogniive Neuroscience article published earlier this year, raise everal concerns when comparing children and adults sing fMRI BOLD data. They do so in the context of iscussing numerous potential age-related changes in neuovascular coupling, neural circuitry, and neural energy use hat have not been widely explored thus far in the develpmental fMRI literature (Harris et al., 2011). Considering hese potential issues, the authors express concern about he feasibility of comparing children and adults using fMRI. We, and others, have previously discussed many imporant elements of study design, analysis, and interpretation n developmental imaging (e.g. Palmer et al., 2004; Church t al., 2010; Poldrack, 2010; Luna et al., 2010; Carp et al., 011). The considerations raised in these discussions, and n the piece by Harris et al., are targeted at developmental maging but really are germane to studies across the lifesan and to studies that compare groups (e.g. patients and ontrols). In their detailed and thoughtful discussion, Harris, eynell, and Attwell focus specifically on what these potenial underlying structural and vascular differences could ean to results of BOLD signal differences found between hildren and adults. This focus on accounting for differnces is understandable as it is differences that are primarly highlighted in developmental (and aging) studies. Thus,