Pain
-
The anterior cingulate cortex (ACC) processes the affective component of pain, whereas the primary somatosensory cortex (S1) is involved in its sensory-discriminative component. Injection of morphine in the ACC has been reported to be analgesic, and endogenous opioids in this area are required for pain relief. Mu opioid receptors (MORs) are expressed in both ACC and S1; however, the identity of MOR-expressing cortical neurons remains unknown. ⋯ Our results suggest a differential contribution of MOR-mediated modulation to ACC and S1 outputs. We also found that females had a greater density of MOR+ neurons compared with males in both areas. In summary, we conclude that MOR-dependent opioidergic signaling in the cortex displays sexual dimorphisms and likely evolved to meet the distinct function of pain-processing circuits in limbic and sensory cortical areas.
-
Randomized Controlled Trial
A double-blind phase II randomized controlled trial of an online cognitive bias modification for interpretation program with and without psychoeducation for people with chronic pain.
Cognitive bias modification for interpretation (CBM-I) is an effective intervention for anxiety, but there is only a single trial in people with chronic pain. The aim of this randomized controlled trial was to test CBM-I with and without psychoeducation for people with chronic pain. We randomized 288 participants to 4 groups comprising treatment (CBM-I vs placebo) with or without psychoeducation. ⋯ Cognitive bias modification of interpretation reduced stress but only for those who also received psychoeducation. This trial shows that CBM-I has promise in the management of pain, but there was limited evidence that psychoeducation improved the efficacy of CBM-I. Cognitive bias modification of interpretation was administered entirely remotely and is highly scalable, but future research should focus on paradigms that lead to better engagement of people with chronic pain with CBM-I.
-
Pain is a global public health problem given its high prevalence and incidence, long duration, and social and economic impact. There is growing interest in nutrition as potential modifiable risk factor related to pain; however, the associations between healthy dietary patterns and pain have not yet been well established. Thus, we aimed to systematically review and synthesise current cross-sectional and longitudinal evidence on the relationship between a priori healthy dietary patterns and noncancer pain among adults aged ≥18 years. ⋯ Despite notable heterogeneity, 50% of included observational studies reported that adherence to a healthy diet, particularly the Mediterranean diet, is inversely associated with pain. Of note, the cross-sectional design of most studies precludes any causal interpretation. Moreover, limited and inconsistent evidence from longitudinal studies highlights the need for further studies.