“…The design matrices of all GLMs included regressors for motion, a high‐pass filter (cutoff period 128 s), and the stimulation blocks convolved by the canonical hemodynamic response function. A set of 14 physiological regressors, generated using an in‐house developed Matlab toolbox (Hutton et al, 2011), were based on cardiac and respiratory traces recorded on Spike2 (Cambridge Electronic Design Limited, Cambridge, UK) with a respiration belt and pulse oximeter. Twelve regressors, based on a set of sine and cosine Fourier series components extending to the third harmonic, were built to model the cardiac and respiratory phase (Glover, Li, & Ress, 2000; Josephs, Howseman, Friston, & Turner, 1997).…”