title: Moving or being moved: that makes a difference.
abstract: During head/body movements, gaze stability is ensured by transformation of motion-related sensory signals into respective motor commands. Passively induced motion in all vertebrates including amphibians evokes a robust vestibulo-ocular reflex, suggesting an equally important role of this motor reaction during actively induced motion. However, during self-induced movements including locomotion, motor efference copies offer a convenient additional substrate for counteracting retinal image displacements. During such locomotor activity in Xenopus laevis tadpoles, spinal central pattern generator-derived efference copies elicit spatio-temporally specific eye movements, which are functionally appropriate to offset swimming-related retinal image displacements. In addition, passively induced horizontal semicircular canal signals are suppressed, making intrinsic spino-extraocular motor coupling the dominating mechanism for gaze stabilization during locomotion. The presence of functionally appropriate efference copy-driven eye movements in adult frogs with limb-based locomotion suggests that this mechanism might play a role for gaze stability during rhythmic locomotion also in other vertebrates.
authors.affiliation: Department Biology II, Ludwig-Maximilians-University Munich, Grosshaderner Str. 2, 82152, Planegg, Germany. straka@lmu.de.
authors.forename: Hans
authors.identifier: http://orcid.org/0000-0003-2874-0441
authors.initials: H
authors.lastname: Straka
authors.affiliation: Department Biology II, Ludwig-Maximilians-University Munich, Grosshaderner Str. 2, 82152, Planegg, Germany.
authors.forename: Boris P
authors.initials: BP
authors.lastname: Chagnaud
mesh_terms: D000818:Animals; D005121:Extremities / Q000502:physiology; D005133:Eye Movements / Q000502:physiology*; D019416:Head Movements / Q000502:physiology*; D008124:Locomotion / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D012665:Semicircular Canals / Q000502:physiology*; D013116:Spinal Cord / Q000166:cytology; D014982:Xenopus laevis
keywords: Efference copy; Extraocular motoneurons; Locomotion; Vestibular system; Xenopus laevis