Cerebellum is more concerned about visceral than somatic pain

Chronic pain disorders are extremely common, including chronic back pain and headaches, but also chronic visceral pain disorders, such as irritable bowel syndrome. Treatment is notoriously difficult. A detailed understanding of the neural pain circuitry is a prerequisite for the development of new treatment options. The cerebellum has become an interesting target for non-invasive and invasive brain stimulations in a wide range of brain disorders and may be a future option in treating chronic pain. The possible contribution of the cerebellum to the pathophysiology of chronic pain has become of interest only recently.1 Although the cerebellum has frequently been shown to respond to painful stimuli, knowledge about the specific contributions of the cerebellum to pain processing remains elusive. Electrophysiological studies in rodents provide evidence that the cerebellum receives afferent input coming from cutaneous and visceral nociceptors.2 Our group and others have found that neural processing of somatic and visceral pain is partly overlapping but reveals also significant differences.3 As yet, however, it is unknown to what extent cerebellar responses differ between visceral and somatic pain. To address this question, we compared pain-related activations of the cerebellum between carefully matched rectal distensions and cutaneous heat stimuli. Functional MRI (fMRI) data were acquired in 22 healthy female participants as part of a previous study.3 fMRI data were reanalysed using a normalising method optimised for the cerebellum. Participants were on average 24.4±0.6 years old with a mean body mass index of 21.9±0.5. Questionnaires confirmed lack …