Fig. 2.

Grayordinate intensity plot for an individual subject. (A) Data are shown before and (B) after the application of a notch filter in the range of respiration. Grayordinate representation for a single subject tracking the spatial root mean square of the derivative of the timeseries (DVARS), the whole brain signal, the FD value and finally the grayordinate plot across the duration of the acquisition. With an FD threshold of 0.2 mm, indicated by the horizontal orange line, any frames that surpass this minimum motion level across the subject timeseries are targeted for removal. Real motion should correspond with an interruption in the grayordinate plot (indicated by red arrow), which is not the case before the application of a respiratory notch filter for many identified frames (marked by black arrows). After the filter is applied, many frames show a decrease in FD and are no longer targeted for frame removal. However, high motion frames caused by spontaneous subject motion and that correspond to an interruption in the grayordinate plot are still targeted for frame removal.