Proprioceptive coupling between the two eyes. A brief, passive stretch of the right eye’s lateral rectus muscle in humans is associated with an increase in the BOLD response in the left oculomotor and abducens nuclei, which innervate the extraocular muscles of the left eye. In complete darkness the left eye’s active movement mirrors the passive movement of the right eye, suggesting a role of extraocular muscle proprioception in ocular alignment (Cover illustration based on Balslev, Mitchell, Faria, Priba, Macfarlane. Proprioceptive contribution to oculomotor control in humans