Recording arrangement and neural pathways of the electrically evoked vestibulocollic reflex in monkey and human. Extracellular single-unit activity of regular and irregular canal afferents in macaque monkeys was recorded using tungsten electrodes during sinusoidal and stochastic electrical vestibular stimulation. Single MU activity was recorded in human sternocleidomastoid and splenius capitis muscles and multi-unit activity was recorded in human and monkey sternocleidomastoid muscle using fine-wire electrodes during the same electrical stimuli. INC, Interstitial nucleus of Cajal; MN, motoneurons; MRST, medial reticulospinal tract; VN, vestibular nuclei; VST, vestibulospinal tract.