Advantages and disadvantages of a fast fMRI sequence in the context of EEG–fMRI investigation of epilepsy patients: A realistic simulation study

Subject‐level reliability analysis of fast fMRI with application to epilepsy

“…Recent studies with MREG have considered using a higher temporal autoregressive order of the noise model than the one traditionally used (usually with order 1) for analyzing EPI data. Two autoregressive models with orders 5 (AR‐5) and 10 (AR‐10) were used for comparison, because order 5 or 6 is what was often used in the literature and order 10 has the theoretical advantage of accounting for the fundamental respiration and cardiac frequencies . In the simulation study , the authors favored 10 over 5 based on the cluster size findings and ROC analysis.…”

“…Two autoregressive models with orders 5 (AR‐5) and 10 (AR‐10) were used for comparison, because order 5 or 6 is what was often used in the literature and order 10 has the theoretical advantage of accounting for the fundamental respiration and cardiac frequencies . In the simulation study , the authors favored 10 over 5 based on the cluster size findings and ROC analysis. The max t‐value analysis favors order 5, as it has a higher value than order 10.…”

“…We used same color bar with range 1-15 for each t-map for ease of comparison. cardiac frequencies (15). In the simulation study (15), the authors favored 10 over 5 based on the cluster size findings and ROC analysis.…”

“…For the autoregressive factor, as MREG has a higher sampling rate than the EPI sequence, some studies have considered using higher autoregressive orders (usually 5 or 10); there is still no clear conclusion and we decided to analyze this problem from the point view of reliability. The orders used to model the temporal autocorrelation of the noise in EPI are low (typically order 1).…”

“…As MREG has 19 times higher temporal sampling, higher orders need to be explored. We evaluated two commonly used orders (13)(14)(15): 5 (AR-5) and 10 (AR-10).…”