title: Sensory-evoked turning locomotion in red-eared turtles: kinematic analysis and electromyography.
abstract: We examined the limb kinematics and motor patterns that underlie sensory-evoked turning locomotion in red-eared turtles. Intact animals were held by a band-clamp in a water-filled tank. Turn-swimming was evoked by slowly rotating turtles to the right or left via a motor connected to the shaft of the band-clamp. Animals executed sustained forward turn-swimming against the direction of the imposed rotation. We recorded video of turn-swimming and computer-analyzed the limb and head movements. In a subset of turtles, we also recorded electromyograms from identified limb muscles. Turning exhibited a stereotyped pattern of (1) coordinated forward swimming in the hindlimb and forelimb on the outer side of the turn, (2) back-paddling in the hindlimb on the inner side, (3) a nearly stationary, "braking" forelimb on the inner side, and (4) neck bending toward the direction of the turn. Reversing the rotation caused animals to switch the direction of their turns and the asymmetric pattern of right and left limb activities. Preliminary evidence suggested that vestibular inputs were sufficient to drive the behavior. Sensory-evoked turning may provide a useful experimental platform to examine the brainstem commands and spinal neural networks that underlie the activation and switching of different locomotor forms.
authors.affiliation: Department of Growth Development and Structure, Southern Illinois University, School of Dental Medicine, Alton, IL, 62002, USA.
authors.forename: Dan B
authors.initials: DB
authors.lastname: Welch
authors.forename: Scott N
authors.initials: SN
authors.lastname: Currie
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004576:Electromyography; D005121:Extremities / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D010812:Physical Stimulation; D012399:Rotation; D013550:Swimming / Q000502:physiology*; D014426:Turtles / Q000502:physiology*
references.citation: J Neurophysiol. 2000 Nov;84(5):2181-90
references.pmid: 11067964
references.citation: J Comp Physiol A. 1990 Aug;167(3):403-12
references.pmid: 2121965
references.citation: J Neurophysiol. 2007 Apr;97(4):3093-108
references.pmid: 17303814
references.citation: J Neurophysiol. 2000 Jan;83(1):146-55
references.pmid: 10634861
references.citation: J Neurosci. 1994 Aug;14(8):5105-19
references.pmid: 8046471
references.citation: Brain Res. 1984 Jun 4;302(1):151-62
references.pmid: 6733501
references.citation: J Exp Biol. 2006 Nov;209(Pt 21):4203-13
references.pmid: 17050835
references.citation: J Exp Biol. 2010 Oct 15;213(Pt 20):3515-26
references.pmid: 20889832
references.citation: J Neurophysiol. 2007 Oct;98(4):2223-31
references.pmid: 17715193
references.citation: J Neurophysiol. 2011 Mar;105(3):1361-71
references.pmid: 21248057
references.citation: J Neurophysiol. 2008 Apr;99(4):1953-68
references.pmid: 18272877
references.citation: J Neurobiol. 1997 Aug;33(2):99-117
references.pmid: 9240368
references.citation: J Exp Biol. 2009 Jan;212(Pt 2):194-209
references.pmid: 19112138
references.citation: J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2005 Nov;191(11):1037-54
references.pmid: 16258746
references.citation: J Exp Biol. 1972 Aug;57(1):15-40
references.pmid: 5075890
references.citation: J Neurophysiol. 1997 Sep;78(3):1394-403
references.pmid: 9310430
references.citation: J Neurophysiol. 2001 Nov;86(5):2257-65
references.pmid: 11698516
references.citation: Brain Res. 1983 Jun 20;269(2):237-50
references.pmid: 6883083
references.citation: J Neurophysiol. 1997 Jul;78(1):214-28
references.pmid: 9242275
references.citation: J Exp Biol. 1995;198(Pt 5):1079-85
references.pmid: 9318896
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2001 Dec;131(1):61-75
references.pmid: 11733167
references.citation: Eur J Neurosci. 2005 Nov;22(9):2271-82
references.pmid: 16262665
references.citation: J Exp Biol. 1994 Jul;192(1):95-106
references.pmid: 9317406
references.citation: J Exp Biol. 2001 Oct;204(Pt 19):3261-71
references.pmid: 11606600
references.citation: J Neurophysiol. 1977 Jul;40(4):768-78
references.pmid: 886370
references.citation: J Neurophysiol. 1997 Sep;78(3):1404-13
references.pmid: 9310431
references.citation: J Morphol. 1971 Jun;134(2):195-214
references.pmid: 5135653
references.citation: J Exp Biol. 1996;199(Pt 7):1477-82
references.pmid: 9319377
references.citation: Neurosci Lett. 2008 Aug 15;441(1):105-9
references.pmid: 18597937
references.citation: J Exp Biol. 2003 May;206(Pt 10):1649-56
references.pmid: 12682097
references.citation: J Neurophysiol. 2008 Mar;99(3):1187-200
references.pmid: 18160423