Functional MRI may not be slice time corrected when time differences are less than one second. However, these differences may be important for causal neuronal relationships. We investigated slice timing correction in spectral dynamic causal modeling using multiband resting-state data with TR = 802 ms from controls and temporal lobe epilepsy patients. Differences investigated were numeric value, parameter interpretation, and group level models. No significant difference in the first two were found. Group level modeling differences were found. Thus, slice timing correction appears necessary when applying spectral dynamic causal modeling even with slice timing differences of less than one second.