Abstract
To assess speed- and gait-related changes in semitendinosus (ST) activity, EMG was recorded from three cats during treadmill locomotion. Selected step cycles were filmed, and hip and knee joint kinematics were synchronized with EMG records. Swing-phase kinetics for trot and gallop steps at 2.25 m/s were compared for gait-related differences. Also, swing kinetics for different gallop forms were compared. With few exceptions, ST-EMG was characterized by two bursts for each step cycle; the first preceded paw off (STpo), and the second preceded paw contact (STpc). The two-burst pattern for the walk was defined by a high-amplitude STpo burst and a brief, low-amplitude STpc burst; at the slowest walk speeds, the STpc burst was occasionally absent. For the trot, the STpo burst was biphasic, with a brief pause just after paw off. With increasing walk-trot speeds, the duration of both bursts (STpo, STpc) remained relatively constant, but recruitment increased. Also, the onset latency of the STpo burst shifted, and a greater proportion of the burst was coincident with knee flexion during early swing. At the trot-gallop transition, there was an abrupt change in the two-burst pattern, and galloping was characterized by a high-amplitude STpc burst and a brief, low-amplitude STpo burst. At the fastest gallop speeds, the STpo burst was often absent, and the reduction in or elimination of the burst was associated with a unique pattern of swing phase kinetics at the knee. Knee flexion during the gallop swing was sustained by two inertial torques related to hip linear acceleration (HLA) and leg angular acceleration (LAA); correspondingly, muscle contraction was unnecessary. Conversely, knee flexion at the onset of the trot swing relied on a flexor muscle torque at the knee acting with an inertial flexor torque (LAA). Rotatory and transverse gallops at 4.0 m/s had similar swing phase kinetics and ST-EMG. Gait-related changes in ST-EMG, particularly at the trot-gallop transition, are not congruent with neural models assuming that details of the ST motor pattern are produced by a spinal CPG. We suggest that motor patterns programed by the spinal CPG are modulated by input from supraspinal centers and/or motion-related feedback from the hindlimbs to provide appropriate gait-specific activation of the ST.
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References
Andersson O, Grillner S (1981) Peripheral control of the cat's step cycle. I. Phase dependent effects of ramp movements of the hip during “fictive locomotion”. Acta Physiol Scand 113:89–101
Barbeau H, Rossignol S (1987) Recovery of locomotion after chronic spinalization in the adult cat. Brain Res 412:84–95
Bodine SC, Roy RR, Meadows DA, Zernicke RF, Sacks RD, Fournier M, Edgerton VR (1982) Architectural, histochemical, and contractile characteristics of a unique biarticular muscle: the cat semitendinosus. J Neurophysiol 48:192–201
Buford JA, Smith JL (1990) Adaptive control for backward quadrupedal walking. II. Hindlimb muscle synergies. J Neurophysiol 64:756–766
Buford JA, Smith JL (1993) Adaptive control for backward quadrupedal walking. III. Stumbling corrective responses and cutaneous reflex sensitivity. J Neurophysiol (in press)
Buford JA, Zernicke RF, Smith JL (1990) Adaptive control for backward quadrupedal walking I. Posture and hindlimb kinematics. J Neurophysiol 64:745–755
Chanaud CM, Pratt CA, Loeb GE (1991) Functionally complex muscles of the cat hindlimb V. The roles of histochemical fiber type regionalization and mechanical heterogeneity in differential muscle activation. Exp Brain Res 85:300–313
Chung SH, Buford JA, and Smith JL (1990) Gait-related EMG patterns of the semitendinosus during locomotion in cats. Soc Neurosci Abstr 16:890
Conway BA, Hultborn H, Kiehn O (1987) Proprioceptive input resets central locomotor rhythm in the spinal cat. Exp Brain Res 68:643–656
Dubuc R, Rossignol S, Lamarre Y (1986) The effects of 4-aminopyridine on the spinal cord: rhythmic discharges recorded from the peripheral nerves. Brain Res 369:243–259
Engberg I, Lundberg A (1969) An electromyographic analysis of muscular activity in the hindlimb of the cat during unrestrained locomotion. Acta Physiol Scand 75:614–630
English AW (1980) The functions of the lumbar spine during stepping in the cat. J Morphol 165:55–66
English AW, Weeks OL (1987) An anatomical and functional analysis of cat biceps femoris and semitendinosus muscles. J Morphol 191:161–175
Forssberg H, Grillner S, Halbertsma JM (1980) The locomotion of the low spinal cat. I. Coordination within a hindlimb. Acta Physiol Scand 108:269–281
Goslow GE, Reinking RM, Stuart DG (1973) The cat step cycle: hind limb joint angles and muscle lengths during unrestrained locomotion. J Morphol 141:1–41
Grillner S (1981) Control of locomotion in bipeds, tetrapods and fish. In: Brooks VB (eds) Handbook of physiology, Vol II American Physiological Society, Baltimore, pp 1179–1236
Grillner S (1985) Neurobiological bases of rhythmic motor acts in vertebrates. Science 228:143–149
Grillner S, Zangger P (1975) How detailed is the central pattern generator for locomotion? Brain Res 88:367–371
Grillner S, Zangger P (1979) On the central generation of locomotion in the low spinal cat. Exp Brain Res 34:241–261
Grillner S, Zangger P (1984) The effect of dorsal root transection on the efferent motor pattern in the cat's hindlimb during locomotion. Acta Physiol Scand 120:393–405
Halbertsma JM (1983) The stride cycle of the cat: the modeling of locomotion by computerized analysis of automatic recordings. Acta Physiol Scand [Suppl 521]: 1–75
Harris-Warrick RM (1988) Chemical modulation of central pattern generators. In: Cohen AH, Rossignol S, Grillner S (eds) Neural control of rhythmical movements in vertebrates. Wiley, New York, pp 285–331
Hildebrand M (1959) Motions of the running cheetah and horse. J Mammal 40:481–495
Hildebrand M (1977) Analysis of asymmetrical gaits. J Mammal 58:131–156
Hildebrand M (1980) The adaptive significance of tetrapod gait selection. Am Zool 20:255–267
Hoffer JA, Sugano N, Loeb GE, Marks WM, O'Donovan MJ, Pratt CA (1987) Cat hindlimb motoneurons during locomotion. III. Functional segregation in sartorius. J Neurophysiol 57:554–562
Hoy MG, Zernicke RF (1985) Modulation of limb dynamics in the swing phase of locomotion. J Biomech 18:49–60
Hoy MG, Zernicke RF (1986) The role of intersegmental dynamics during rapid limb oscillations. J Biomech 19:867–877
Hutchison DL, Roy RR, Bodine-Fowler S, Hodgson JA, Edgerton VR (1989) Electro-myographic (EMG) amplitude patterns in the proximal and distal compartments of the cat semitendinosus during various motor tasks. Brain Res 479:56–64
Kirk RE (1982) Experimental design: procedures for the behavioral sciences. Brooks-Cole Belmont
Loeb GE, Duysens J (1979) Activity pattern in individual hindlimb primary and secondary muscle spindle afferents during normal movements in unrestrained cats. J Neurophysiol 42:420–440
Lundberg A (1969) Reflex control of stepping. The Nansen memorial lecture V. Universitetsforlaget, Oslo, pp 1–42
Lundberg A (1980) Half-centres revisited. In: Szentagothai J, Palkovits M, Hamori J (eds) Regulatory functions of the CNS, motion and organization principles, Pergamon Press/Academiai Kiado, Budapest, pp 155–167
Pearson KG (1987) Central pattern generation: a concept under scrutiny. In: Lennan HM, Ledsome JR, McIntosh CHS, Jones DR (eds) Advances in physiological research. Plenum, New York, pp 167–185
Pearson KG, Rossignol S (1991) Fictive motor patterns in chronic spinal cats. J Neurophysiol 66:1874–1887
Perret C, Cabelguen JM (1976) Central and reflex participation in the timing of locomotor activations of a bifunctional muscle, the semi-tendinosus, in the cat. Brain Res 106:390–395
Perret C, Cabelguen JM (1980) Main characteristics of the hindlimb locomotor cycle in the decorticate cat with special reference to bifunctional muscles. Brain Res 187:333–351
Peter SE, Rick C (1977) The action of three hamstring muscles in the cat: a mechanical analysis. J. Morphol 125:315–327
Pratt CA, Loeb GE (1991) Functionally complex muscles of the cat hindlimb. I. Patterns of activation across sartorius. Exp Brain Res 85:243–256
Rasmussen S, Chan AK, Goslow GE (1978) The cat step cycle: electromyographic patterns for hindlimb muscles during posture and unrestrained locomotion. J Morphol 155:253–270
Shik ML, Severin FV, Orlovsky GN (1966) Control of walking and running by means of electrical stimulation of the mid-brain. Biophysics 11:756–765
Smith JL (1986) Hindlimb locomotion of the spinal cat: synergistic patterns, limb dynamics and novel blends. In: Grillner S, Stein PSG, Stuart DG, Forssberg H, Herman RM (eds) Neurobiology of vertebrate locomotion. Macmillan, London, Vol 45, pp 185–199
Smith JL, Zernicke RF (1987) Predictions for neural control based on limb dynamics. Trend Neurosci 10:123–128
Smith JL, Chung SH, Buford JA, Zernicke RF (1991) Quadrupedal gallop: the unstudied gait. Soc Neurosci Abstr 17:1225
Wisleder D, Zernicke RF, Smith JL (1990) Speed-related effects on intersegmental dynamics during the swing phase of cat locomotion. Exp Brain Res 79:651–660
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Smith, J.L., Chung, S.H. & Zernicke, R.F. Gait-related motor patterns and hindlimb kinetics for the cat trot and gallop. Exp Brain Res 94, 308–322 (1993). https://doi.org/10.1007/BF00230301
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DOI: https://doi.org/10.1007/BF00230301