Altered Amygdala-prefrontal Connectivity in Chronic Nonspecific Low Back Pain: Resting-state fMRI and Dynamic Causal Modelling Study

•Amygdala contains heterogeneous nuclei presented with distinct functions.•Low back pain accompanies by negative emotion related to amygdala function.•Dynamic causal modelling can describe the connectivity direction in chronic pain states.•Greater resting-state functional connectivity of amygdala-medial prefrontal pathway was seen in chronic low back pain.•Lower effective connectivity of medial prefrontal-to-amygdala pathway was suggested in chronic low back pain.