Tailored HRF Analysis of Canine BOLD Responses

Resting-state data were used to calculate subject-specific tSNR maps. Task data were used to estimate the subject-specific BOLD response to visual stimulation using SPM12’s default settings for a first-level single-subject t test (task > 0). However, instead of SPM12’s canonical hemodynamic response function (HRF), we used a tailored dog HRF in the analysis of the data (Boch et al., 2021 (link)) to account for the faster BOLD response in dogs. The resulting single-subject statistical parametric maps of t values were transformed into z-values to allow for second-level group analysis. On the group level, we compared tSNR and activation maps between the two coils statistically using paired t tests in SPM with a threshold of p < 0.05. We used a canine brain atlas (Nitzsche et al., 2019 (link)) for parcellation to investigate brain area specific differences.