Tonic pain alters functional connectivity of the descending pain modulatory network involving amygdala, periaqueductal gray, parabrachial nucleus and anterior cingulate cortex. - Timothy J. Meeker; Anne-Christine Schmid; Michael L. Keaser; Shariq A. Khan; Rao P. Gullapalli; Susan G. Dorsey; Joel D. Greenspan; David A. Seminowicz (NeuroImage, 2022)