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GBefore averaging the values in each voxel, one option is to remove any ÒuninterestingÓ time lags and average only those time lag points that matter
åIn this example, ÒuninterestingÓ refers to time lags whose percent signal change value is close to zero
åIf we included these uninteresting time lags in our mean calculation, they would pull the mean closer to zero, making it more difficult to pick up any statistically significant results in the ANOVA
GIn this example, the IRF is fairly small from time lags 0-3, but begins to spike up at time lag 4.  It peaks at time lag 7, declines at 9, drops sharply by 10, and decreases steadily from there.
åGiven this information, one option                                                             is to compute the mean percent                                                                                   signal change for time lags 4-9                                                              only
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