Figure 1.

McDonald’s napkin on which “Hammer” – the initial clustered volume acquisition (CVA) sequence for auditory imaging – was developed by Tom Talavage and Whitney Edmister over a cheap dinner, on Wednesday, April 16, 1997. A: After a description by Tom regarding how the equal spacing between slice acquisitions (right set of vertical lines) led to masking of stimuli, Whitney proposed “clustering” the acquisitions and leaving a gap (left set of vertical lines). B: Given this option, an alternate means to measure the response to any given stimulus, contrasting presentation of the stimulus (top) with no stimulus (bottom), noting that only the first few images of this latter acquisition would be free of the (sketched) hemodynamic response to the volume acquisition. C: Conceptual structure for sequence operation in which a long gap (here, 10s; initially including RF excitation at fixed intervals when not acquiring images) would precede a 1–2s acquisition. D: Initial vision for how the sequence would be constructed within the TR period, including prediction of how the induced change in fMRI response would decrease with increasing TR. E: Given that each acquisition would produce a hemodynamic response, longer TRs would also be expected to minimize interaction across acquisitions. F: Plan for experiment to be conducted using increasing gaps between acquisitions (i.e., increasing TR) to evaluate benefits of CVA for auditory fMRI, ultimately the basis of Edmister et al. (1999).