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Strategies for the control of voluntary movements with one mechanical degree of freedom

Published online by Cambridge University Press:  04 February 2010

Gerald L. Gottlieb*
Affiliation:
Department of Physiology, Rush Medical College, Chicago, IL 60612*
Daniel M. Corcos
Affiliation:
Department of Physical Education, University of lllinois at Chicago, Chicago, IL 60680
Gyan C. Agarwal
Affiliation:
Departments of Electrical Engineening and Computer Science, and Bioengineering, University of lllinois at Chicago, Chicago, IL 60680 Electronic mail: [email protected]
*
* Please address all correspondence to Gerald L. Gottlieb

Abstract

A theory is presented to explain how accurate, single-joint movements are controlled. The theory applies to movements across different distances, with different inertial loads, toward targets of different widths over a wide range of experimentally manipulated velocities. The theory is based on three propositions. (1) Movements are planned according to “strategies” of which there are at least two: a speed-insensitive (SI) and a speed-sensitive (SS) one. (2) These strategies can be equated with sets of rules for performing diverse movement tasks. The choice between SI and SS depends on whether movement speed and/or movement time (and hence appropriate muscle forces) must be constrained to meet task requirements. (3) The electromyogram can be interpreted as a low-pass filtered version of the controlling signal to the motoneuron pools. This controlling signal can be modelled as a rectangular excitation pulse in which modulation occurs in either pulse amplitude or pulse width. Movements to different distances and with loads are controlled by the SI strategy, which modulates pulse width. Movements in which speed must be explicitly regulated are controlled by the SS strategy, which modulates pulse amplitude. The distinction between the two movement strategies reconciles many apparent conflicts in the motor control literature.

Type
Target Articles
Copyright
Copyright © Cambridge University Press 1989

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References

Abbott, B. C. & Aubert, X. M. (1952) The force exerted by active striated muscle during and after change of length. Journal of Physiology 117:7786. [CCAMC]CrossRefGoogle ScholarPubMed
Abbs, J. H., Cracco, V. L. & Cole, K. L. (1984) Control of multimovement coordination: Sensorimotor mechanisms in speech motor programming. Journal of Motor Behavior 16:195231. [rGLC, BDB]Google Scholar
Abdusamatov, R. M., Adamovich, S. V., Berkinblit, M. B., Chernavsky, A. V. & Feldman, A. C. (1989) Rapid one-joint movements: A qualitative model and its experimental verification. In: Stance and motion: Facts and concepts, ed. Curfinkel, V. S., Ioffe, M. E.Massion, J. & Roll., J. P.Plenum. [SVA]Google Scholar
Abdusamatov, R. M., Adamovich, S. V. & Feldman, A. C. (1987) A model for one-joint motor control in man. In: Motor control, ed. Cantchev, C. N., Dimitrov, B. & Catev, P.Plenum. [SVA, MLL]Google Scholar
Abdusamatov, R. M. & Feldman, A. G. (1986) Description of the electromyograms with the aid of a mathematical model for single joint movements. Biophysics 31:549–52. [MLL]Google Scholar
Abend, W., Bizzi, E. & Morasso, P. (1982) Human arm trajectory formation. Brain 105:331–48. [WAM]Google Scholar
Accornero, N., Beradelli, M. A. & Manfredi, M. (1984) Two-joint ballistic arm movements. Neuroscience Letters 46:9195. [TF]Google Scholar
Adamovich, S. V., Boiko, M. I. & Feldman, A. G. (1982) Superposition of central commands during movement generation in human elbow joint. Proceedings of the First Biophysical Congress, Moscow: 4. [SVA]Google Scholar
Adamovitch, S. V., Burlachkova, N. I. & Feldman, A. G. (1984) Wave nature of the central process of formation of the trajectories of change in the joint angle in man. Biophysics 29:130–34. [MLL]Google Scholar
Adamovitch, S. V. & Feldman, A. G. (1984) Model of the central regulation of the parameters of motor trajectories. Biofizika 29:306–9 (English translation, 338–42). [aGLG, SVA, TF, MLL]Google Scholar
Adrian, E. D. & Bronk, D. W. (1929) The discharge of impulses in motor nerve fibers. Part II: The frequency of discharge in reflex and voluntary contractions. Journal of Physiology (London) 67:119–51. [aGLG]Google Scholar
Agarwal, G. C. & Gottlieb, G. L. (1975) An analysis of the electromyogram by Fourier. simulation and experimental techniques. IEEE Transactions on Biomedical Engineering BME 22:225–29. [aGLG]CrossRefGoogle ScholarPubMed
Agarwal, G. C. (1982) Mathematical modeling and simulation of the postural control loop: Part I. Critical Reviews in Biomedical Engineering 8:493–98. [aGLG. UW]Google ScholarPubMed
Angel, R. W. (1974) Electromyography during voluntary movement: The two- burst pattern. Electroencephalography and Clinical Neurophysiology 36:493–98. [aGLG]Google Scholar
Angel, R. W. (1977) Antagonist muscle activity during rapid arm movements: Central versus proprioceptive influences. Journal of Neurology, Neurosurgery and Psychiatry 40:683–86. [WAM]Google Scholar
Asatryan, D. G. & Feldman, A. G. (1965) Functional tuning of the nervous system with control of movements or maintenance of a steady posture. I: Mechanographic analysis of the work of the limb on execution of a postural task. Biophysics 10:925–35. [MLL]Google Scholar
Atkeson, C. C. & Hollerbach, J. M. (1985) Kinematic features of unrestrained vertical arm movements. Journal of Neuroscience 5:2318–30. [TF]Google Scholar
Bahill, A. T., Clark, M. & Stark, L. (1975a) The main sequence, a tool for studying human eye movements. Mathematical Biosciences 24:191204. [BB. CG]Google Scholar
Bahill, A. T. (1975b) Glissades– eye movements generated by mismatched components of the saccadic motoneuronal control signal. Mathematical Biosciences 26:303–18. [BB]Google Scholar
Baird, J. C. & Noma, E. (1978) Fundamentals of scaling and psychophysics. Wiley. [HH]Google Scholar
Baldissera, F., Campadelli, P. & Piccinelli, L. (1982) Neural encoding of input transients investigated by intracellular injection of ramp currents in cat α-motoneurones. Journal of Physiology 328:7386. [UW]Google Scholar
Baldissera, F., Campadelli, P. & Piccinelli, L. (1984) The dynamic response of cat is-motoneurones investigated by intracellular injection of sinusoidal currents. Experimental Brain Research 54:275–82. [UW]Google Scholar
Bartlett, F. C. (1932) Remembering: A study in experimental and social psychology. Cambridge University Press. [aGLG]Google Scholar
Basmajian, J. V. & De Luca, C. J. (1985) Muscles alive. 5th edition. Waverly Press. [aGLG]Google Scholar
Benecke, B., Meinck, H.-M. & Conrad, B. (1985) Rapid goal-directed elbow flexion movements: Limitations of the speed control system due to neural constraints. Experimental Brain Research 59:470–77. [aGLG, DSH]Google Scholar
Berardelli, A., Rothwell, J. C., Day, B. L., Kachi, T. & Marsden, C. D. (1984) Duration of the first agonist burst in ballistic arm movements. Brain Research 304:183–87. [aGLG, MH]Google Scholar
Berkinblit, M. B., Feldman, A. G. & Fukson, O. I. (1986) Adaptability of innate motor patterns and motor control mechanisms. Behavioral and Brain Sciences 9:585638. ]aGLG, MLL]Google Scholar
Bernstein, N. A. (1935) The problem of interrelation between coordination and localization. Archives of Biological Sciences 38:135 (in Russian). [MLL]Google Scholar
Bernstein, N. A. (1967) The coordination and regulation of movements. Pergamon. [aGLG, SVA, PJC, MLL]Google Scholar
Bigland, B. & Lippold, O. C. J. (1954) The relation between force, vepubnity, and integrated electrical activity in human muscles. Journal of Physiology (London) 123;214–4. [aGLG]Google Scholar
Binet, A. & Courtier, J. (1893) Sur la vitesse des mouvements graphiques. Revue Philosophique 35:664–71. [aGLG]Google Scholar
Bizzi, E. (1980) Central and peripheral mechanisms in motor control. In: Tutorials in motor behavior, ed. Stelmach, C. E. & Requin., J.North- Holland. [MLL]Google Scholar
Bizzi, E., Aaccornero, N., Chapple, W. & Hogan, N. (1982) Arm trajectory formation in monkeys. Experimental Brain Research 46:139–43. [JASK, MLL]Google Scholar
Bouisset, S. & Goubel, F. (1968) Interdependence of relations between integrated EMC and diverse biomechanical quantities in normal voluntary movements. Electromyography 8 (Suppl. 1):151–62. [aGLG]Google Scholar
Bouisset, S. & Goubel, F. (1973) Integrated electromyographical activity and muscle work. journal of Applied Physiology 35:696702. [aGLG]Google Scholar
Bouisset, S. & Lestienne, F. (1974) The organization of simple voluntary movement as analyzed from its kinematic properties. Brain Research 71:451–57. [aGLG]CrossRefGoogle Scholar
Bouisset, S., Lestienne, F. & Maton, B. (1977) The stability of synergists in agonists during the execution of a simple voluntary movement. Electroencephalography and Clinical Neurophysiology 42:543–51. [aGLG]Google Scholar
Bridgeman, B. (1983) Phasic eye movement control appears before tonic control in human fetal development, Investigative Ophthalmology and Visual Science 24:658–59. [BB]Google Scholar
Bridgeman, B. (1986) Multiple sources of outflow in processing spatial information. Acta Psychologica 63:3548. [BB]Google Scholar
Brooks, V. B. (1979) Motor programs revisited. In: Posture and movement: Perspective for integrating sensory and motor research on the mammalian nervous system, ed. Talbott, B. E. & Humphrey, D. H.. Raven. [aGLG]Google Scholar
Brown, S. H. & Cooke, J. D. (1981) Amplitude- and instruction-dependent modulation of movement-related electromyogram activity in humans. journal of Physiology (London) 316:97107. [aGLG, ZH]Google Scholar
Brown, S. H. & Cooke, J. D. (1984) Initial agonist burst duration depends on movement amplitude. Experimental Brain Research 55:523–27. [aGLG, MH, WAM]Google Scholar
Bullock, D. & Crossberg, S. (1988a) Neural dynamics of planned arm movements: Emergent invariants and speed-accuracy properties during trajectory formation. Psychological Review 95:4990. [rGLG, DB]Google Scholar
Bullock, D. & Crossberg, S. (1988b) The VITE model: A neural command circuit for generating arm and articulator trajectories. In: Dynamic patterns in complex systems. ed. Kelso, J. A. S., Mandell, A. J. & Schlesinger., M. F.World Scientific. [rGLG, DB]Google Scholar
Bullock, D. & Crossberg, S. (1988c) Neuromuscular realization of planned arm movement trajectories. Neural Networks 1 (Suppl. 1):329. [DB]Google Scholar
Bullock, D. & Crossberg, S. (1988d) The neural control of arm and speech movements: A shared architecture for trajectory generation. Neural Networks 1 (Suppl. 1):328. [DB]Google Scholar
Carlton, L. G. (1981) Processing visual information for movement control. Journal of Experimental Psychology: Human Perception and Performance. 7:1019–30. [rGLG]Google ScholarPubMed
Cavanagh, P. R. & Komi, P. V. (1979) Electromechanical delay in human muscle under eccentric and concentric contractions. European Journal of Applied Physiology 42:159–63. [aGLG]Google Scholar
Cheron, C. & Codaux, E. (1986) Self-terminated fast movement of the forearm in man: Amplitude dependence of the triple-burst pattern. journal Biophysique et Bioméchanique 10:109–17. [aGLG, EG, DSH, MLL]Google Scholar
Christakos, C. N., Windhorst, U., Rissing, B. & Meyer-Lohmann, J. (1987) Frequency response of spinal Renshaw cells activated by stochastic motor axon stimulation. Neuroscience 23:613–23. [UW]Google Scholar
Clark, M. & Stark, L. (1974) Control of human eye movements. III: Dynamic characteristics of the eye tracking mechanism. Mathematical Biosciences 20:213–38. [BB]Google Scholar
Cleveland, S. & Ross, H. C. (1977) Dynamic properties of Renshaw cells: Frequency response characteristics. Biological Cybernetics 27:175–84. [UW]Google Scholar
Cooke, J. D. (1980) The organization of simple skilled movements. In: Tutorials in motor behavior, ed. Stelmach, G. E. & Requin., J.North- Holland. [aGLG, JASK]Google Scholar
Cooke, J. D. & Brown, S. H. (1985) Science and statistics in motor physiology. journal of Motor Behavior 17:489–92. [aGLG rsqb;Google Scholar
Corcos, D. M., Agarwal, G. C. & Cottlieb, G. L. (1985) A note on accepting the null hypothesis: Problems with respect to the mass-spring and pulsestep models of movement control, Journal of Motor Behavior 17:481- 87. [aGLG]Google Scholar
Corcos, D. M., Gottlieb, G. L., Agarwal, G. C. & Liubinskas, T. J. (1986) Effect of inertial load on agonist and antagonist EMC patterns. Proceedings of the 22nd Annual Conference on Manual Control: 219 32 [aGLG]Google Scholar
Corcos, D. M., Gottlieb, C. L. & Agarwal, G. C. (1988) Accuracy constraints upon rapid elbow movements. Journal of Motor Behavior 20:255–72. [arGLG]Google Scholar
Corcos, D. M., (in press) Organizing principles for single joint movements. II: A speedsensitive strategy. journal of Neurophysiology. [arGLG]Google Scholar
Cordo, P. J. (1987) Mechanisms controlling accurate changes in elbow torque in humans, Journal of Neuroscience 7:432–42. [CG]CrossRefGoogle ScholarPubMed
Cruse, H. (1986) Constraints for joint angle control of the human arm. Biological Cybernetics 54:125–32. [HH]Google Scholar
Danoff, J. V. (1979) The integrated electromyogram related to angular vepubnity. Electromyogrphy and Clinical Neurophysiology 19:165–74. [aGLG]Google Scholar
Denier van der Gon, J. J. (1979) Spontaneity in motor expression and the art of playing the spinal c(h)ord. In: Authentication in the visual arts, ed. Jaffe, H. L. C., Leeuwen, J. Storm van & van der Tweel, L. H.. Israel, B. M.. [CCAMG]Google Scholar
Denier van der Con, J. J. & Turing, J. P. (1965) The guiding of human writing movements. Kybernetik 2:145–48. [CCAMG, JPW]Google Scholar
Diener, H. C., Horak, F. B. & Nashner, L. M. (1988) Influence of stimulus parameters on human postural responses. journal of Neurophysiology 59:18881905. [PJC]Google Scholar
Droulez, J. & Berthoz, A. (1986) Servo-controlled (conservative) versus topological (projective) mode of sensory motor control. In: Disorders of posture and gait, ed. Bles, W. & Brandt, T.. Elsevier. [PJC]Google Scholar
Enoka, B. M. (1983) Muscular control of a learned movement: The speed control system hypothesis. Experimental Brain Research 51:135–45. [MLL]Google Scholar
Feldman, A. G. (1966) Functional tuning of the nervous system with control of movement or maintenance of a steady posture. III: Mechanographic analysis of execution by man of the simplest motor tasks. Biophysics 11:766–75. [JASK]Google ScholarPubMed
Feldman, A. G. (1979) Central and reflex mechanisms of motor control (in Russian). Nauka. [MLL]Google Scholar
Feldman, A. C. (1986) Once more on the equilibrium-point hypothesis (λ model) for motor control, journal of Motor Behavior 18:1754. [aGLG, SVA, DB, JASK, M LL]Google Scholar
Feldman, A. G. & Latash, M. L. (1982) Interaction of afferent and efferent signals underlying joint position sense: Empirical and theoretical approaches. Journal of Motor Behavior 14:174–93. [MLL]Google Scholar
Fitts, P. M. (1954) The information capacity of the human motor system in controlling the amplitude of movement, Journal of Experimental Psychology (47:381–91.) [GLG, CG]Google Scholar
Fitts, P. M. & Peterson, J. H. (1964) Information capacity of discrete motor responses. Journal of Experimental Psychology 67:103–12. [aGLG]Google Scholar
Flanders, M. & Cordo, P. J. (1987) Quantification of peripherally induced reciprocal activation during voluntary muscle contraction. Elect roencephalography and Clinical Neurophysiology 67:389–94. [M F]Google Scholar
Flanders, M., Cordo, P. J. & Anson, J. G. (1986) Interaction between visually and kinesthetically triggered voluntary responses. Journal of Motor Behavior 18:427–48. [MF]Google Scholar
Flash, T. (1987) the control of hand equilibrium trajectories in multi-joint arm movements. Biological Cybernetics 57:257–74. [TF]Google Scholar
Flash, T. & Hogan, N. (1985) The coordination of arm movements: An experimentally confirmed mathematical model. Journal of Neuroscience 7:16881703. [TF, JPW]Google Scholar
Fournier, E., Katz, R. & Pierrot-Deseilligny, E. (1983) Descending control of reflex pathways in the production of voluntary isolated movements in man. Brain Research 288:375–77. [CG]Google Scholar
Freeman, F. N. (1914) Experimental analysis of the writing movement. Psychological Review Monographs 17:146. [aGLG]Google Scholar
Freund, H.-J. (1986) Time control of hand movements. Progress in Brain Research 64:287–94. [aGLG]Google Scholar
Freund, H.-J. & Budingen, H. J. (1978) The relationship between speed and amplitude of the fastest voluntary contractions of human arm muscles. Experimental Brain Research 31:112. [arGLG, EG, MH, JPW]Google Scholar
Georgopoulos, A. P. (1986) On reaching. Annual Review of Neuroscience 9:147–70. [TF]Google Scholar
Georgopoulos, A. P., Kalaska, J. F. & Massey, J. T. (1981) Spatial trajectories and reaction times of aimed movements: Effects of practice, uncertainty, and change in target pubnation, Journal of Neurophysiology 46:725–43. [DB]Google Scholar
Georgopoulos, A. P., Schwartz, A. B. & Kettner, R. E. (1986) Neural population coding of movement direction. Science 233:1416–19. [TF]Google Scholar
Ghez, C. (1979) Contributions of central programs to rapid limb movements in the cat. In: Integration in the nervous system, ed. Asanuma, H. & Wilson, V. J.Igaku-Shoin. [aGLG, CG]Google Scholar
Ghez, C. & Cordon, J. (1987) Trajectory control in targeted force impulses. I: Role of opposing muscles. Experimental Brain Research 67:225–40. [aGLG, CG]Google Scholar
Ghez, C. & Martin, J. H. (1982) The control of rapid limb movement in the cat. III: Agonist-antagonist coupling. Experimental Brain Research 45:115–25. [CG]Google Scholar
Ghez, C. & Vicario, O. (1978) The control of rapid limb movements in the cat. II: Scaling of rapid force adjustments. Experimental Brain Research 33:191203. [aGLG]Google Scholar
Gibson, A. R., Houk, J. C. & Koblerman, N. J. (1985a) Magnocellular red nucleus activity during different types of limb movement in the macaque monkey. Journal of Physiology (London) 358:527–49. [JCH]Google Scholar
Gibson, A. R., Houk, J. C. & Koblerman, N. J.(1985b) Relation between red nucleus discharge and movement parameters in trained macaque monkeys. Journal of Physiology (London) 358:551–70. [JCH]Google Scholar
Gibson, J. E. (1963) Nonlinear automatic control. McCraw-Hill. [rGLG]Google Scholar
Gielen, C. C. A. M., van den Oosten, K. & Pull, ter Gunne F. (1985) Relation between EMC activation patterns and kinematic properties of aimed movements. Journal of Motor Behavior 17:421–42. [aGLG]Google Scholar
Glencross, D. J. & Barrett, N. C. (1989) Discrete movements. In: Human skills, 2nd edition, ed. Holding., D. H.Wiley. [DHH]Google Scholar
Gordon, J. & Chez, C. (1987a) Trajectory control in targeted force impulses. II: Pulse height control. Experimental Brain Research 67:241–52. [arGLG, CG, SAW]Google Scholar
Cordon, J. & Chez, C. (1987b) Trajectory control in targeted force impulses. III: Compensatory adjustments for initial errors. Experimental Brain Research 67:253–69. [aGLG, CG, CCAMG]Google Scholar
Gottlieb, G. L. & Agarwal, G. C. (1970) Filtering of electromyographic signals. American journal of Physical Medicine 49:142–46. [DSH]Google Scholar
Gottlieb, G. L. & Agarwal, G. C. (1971) Dynamic relationship between isometric muscle tension and the electromyogram in man. Journal of Applied Physiology 30:345–51. [aGLG]Google Scholar
Gottlieb, G. L., & Agarwal, G. C. (1980) Response to sudden torques about ankle in man. III: Suppression of stretch-evoked responses during phasic contraction. Journal of Neurophysiology 44:233–46. [aGLG, MLL]Google Scholar
Gottlieb, G. L. & Agarwal, G. C. (1982) Control theoretic concepts and motor control. Behavioral and Brain Sciences 5:546–47. [ZH]Google Scholar
Gottlieb, G. L., Corcos, D. M. & Agarwal, G. C. (in press) Organizing principles for single joint movements. I:The speed-insensitive strategy. Journal of Neurophysiology. [arGLG]Google Scholar
Gottlieb, G. L., Corcos, D. M., Agarwal, G. C. & Latash, M. (submitted) Organizing principles for single joint movements, III. The speed insensitive strategy by default. [rGLG]Google Scholar
Gottlieb, C. L., Corcos, D. M., Jaric, S. & Agarwal, G. C. (1989) Practice improves even the simplest movements. Experimental Brain Research 73:435–40. [aGLG]Google Scholar
Gracco, V. L. & Abbs, J. H. (1985) Dynamic control of the perioral system during speech: Kinematic analyses of autogenic and nonautogenic sensorimotor processes. Journal of Nenroplaysiology 54:418–32. [DB]Google Scholar
Graham, C. & McRuer, D. (1961) Analysis of nonlinear control systems. Dover Publications. [rGLG]Google Scholar
Granit, R. (1970) The basis of motor control. Academic Press. [UW]Google Scholar
Gravel, D., Belanger, A. L. & Richards, C. L. (1987) Study of human contraction using electrically evoked responses during passive shortening and lengthening movements. European Journal of Applied Physiology 56:623–27. [aGLC]Google Scholar
Greene, P. (1982) Why is it easy to control your arms? Journal of Motor Behavior 4: 260–86. [aGLG]CrossRefGoogle Scholar
Grillner, S. (1981) Control of locomotion in bipeds, tetrapods, and fish. In: Handbook of physiology, sec. 1: The nervous system. vol. 2: Motor control, ed. Brooks, V. B.. American Physiological Society. [CG]Google Scholar
Grossberg, S. (1973) Contour enhancement, short-term memory, and constancies in reverberating neural networks. Studies in Applied Mathematics 52: 217–57. [DB]Google Scholar
Hallett, M., Berardelli, A., Matheson, J., Rothwell, J. C. & Marsden, C. D. (submitted) Physiological analysis of simple rapid movements in patients with cerebellar deficits. [MH]Google Scholar
Hallett, M. & Marsden, C. D. (1979) Ballistic flexion movements of the human thumb, Journal of Physiology (London) 294:3350. [aGLG, MH]Google Scholar
Hallett, M., Shahani, B. T. & Young, R. R. (1975) EMC analysis of stereotyped voluntary movements in man. Journal of Neurology, Neurosurgery, and Psychiatry 38:1154–62. [aGLG, MLL]Google Scholar
Hallett, M., Shahani, B. T. & Young, R. R. (1975 a) EMC analysis of patients with cerebellar deficits, Journal of Neurology, Neurosurgery, and Psychiatry 38:1163–69. [WAM]Google Scholar
Hancock, P. A. & Newell, K. M. (1985) The movement speed-accuracy relationship in space-time. In: Motor behavior: Programming, control, and acquisition, ed. Heuer, H., Kleinbeck, U. & Schmidt, K. H.. Springer-Verlag. [aCLG]Google Scholar
Hannaford, B., Lakshminarayanan, V. & Stark, L. (1984) Electromyographic of neurological controller signals with viscous load. Journal of Motor Behavior 16:255–74. [CR]Google Scholar
Hannaford, B. & Stark, L. (1985) Roles of the elements of the triphasic control signal. Experimental Neurology 90:619–34. aGLG, CR]Google Scholar
Hannaford, B. (1987) Late agonist activation burst (PC) required for optimal head movement: A simulation study. Biological Cybernetics 57:321–30. [CR]Google Scholar
Hasan, Z. (1986) Optimized movement trajectories and joint stiffiacss in unperturbed, inertially loaded movements. Biological Cybernetics 53:373–82. [JPW]Google Scholar
Hasan, Z. & Enoka, R. M. (1985) Isometric torque-angle relationship and movement-related activity of human flexors: Implications for the equilibrium-point hypothesis. Experimental Brain Research 59:441- 50. [aGLC]Google Scholar
Hasan, Z., Enoka, R. M. & Stuart, D. G. (1985) The interface between biomechanics and neurophysiology in the study of movement: Some recent approaches. Exercise and Sport Science Reviews 13:169234. [aGLC]Google Scholar
Hasan, Z. & Karat, G. M. (1987) Asynchronous initiation of coordinated rotations about the shoulder and elbow. Abstracts of the Society for Neuroscience 13:715. [GEL]Google Scholar
Hasan, Z. & Stuart, D. C. (1988) Animal solutions to problems of movement control: The role of proprioceptors. Annual Review of Neuroscience 11:199223 [SVA]Google Scholar
Henig, W., Favilla, M. & Ghez, C. (1988) Trajectory control in targeted force adjustments for initial errors. Experimental Brain Research 67:253–69. [aGLC, CC, CCAMG]Google Scholar
Gottlieb, C. L. & Agarwal, G. C. (1970) Filtering of electromyographic signals. American journal of Physical Medicine 49: 142–46. [DSH]Google Scholar
Gottlieb, G. L. (1971) Dynamic relationship between isometric muscle tension and the electromyogram in man. Journal of Applied Physiology 30:345–51. [aGLG]Google Scholar
Gottlieb, G. L. (1980) Response to sudden torques about ankle in man. III: Suppression of stretch-evoked responses during phasic contraction. Journal of Neurophysiology 44:233–46. [aGLC, MLL]Google Scholar
Gottlieb, G. L. (1982) Control theoretic concepts and motor control. Behavioral and Brain Sciences 5:546–47. [ZH]Google Scholar
Gottlieb, C. L., Corcos, D. M. & Agarwal, G. C. (in press) Organizing principles for single joint movements. I: A speed-insensitive strategy. Journal of Neurophysiology. [arGLG]Google Scholar
Cottlieb, C. L., Corcos, D. M.. Agarwal, G. C. & Latash, M. (submitted) Organizing principles for single joint movements, III. The speed insensitive strategy by default. [rGLC]Google Scholar
Cottlieb, C. L., Corcos, D. M., Jaric, S. & Agarwal, G. C. (1989) Practice improves even the simplest movements. Experimental Brain Research 73:435–40. [aCLG]Google Scholar
Gracco, V. L. & Abbs, J. H. (1985) Dynamic control of the perioral system during speech: Kinematic analyses of autogenic and nonautogenic sensor motor processes. Jonrmd of Neuroplaysiology 54:418–32. [DB]Google Scholar
Graham, G. & McRuer, D. (1961) Analaysis of nonlinear control systems. Dover Publications. ‘rGLG’Google Scholar
Granit, R. (1970) The basis of motor control. Academic Press. [UW]Google Scholar
Gravel, D., Belanger, A. L. & Richards, C. L. (1987) Study of human contraction using electrically evoked responses during passive shortening and lengthening movements. European Journal of Applied Physiology 56:623–27. [aGLC]Google Scholar
Greene, P. (1982) Why is it easy to control your arms? Journal of Motor Behavior 4:260–86. [aCLG]Google Scholar
Grillner, S. (1981) Control of locomotion in bipeds, tetrapods, and fish. In: Handbook of physiology, sec. 1: The nervous system. vol. 2: Motor control, ed. Brooks, V. B.. American Physiological Society. [CC]Google Scholar
Grossberg, S. (1973) Contour enhancement, short-term memory, and constancies in reverberating neural networks. Studies in Applied Mathematics 52:217–57. [DB]Google Scholar
Hallett, M., Berardelli, A., Matheson, J., Rothwell, J. C. & Marsden, C. D. (submitted) Physiological analysis of simple rapid movements in patients with cerebellar deficits. [MH]Google Scholar
Hallett, M. & Marsden, C. D. (1979) Ballistic flexion movements of the human thumb, Journal of Physiology (London) 294:3350. [aGLG, MH]Google Scholar
Hallett, M., Shahani, B. T. & Young, R. R. (1975) EMC analysis of stereotyped voluntary movements in man. Journal of Neurology, Neurosurgery, and Psychiatry 38:1154–62. [aGLG, MLL]Google Scholar
Hallett, M., (1975a) EMC analysis of patients with cerebellar deficits, Journal of Neurology, Neurosurgery, and Psychiatry 38:1163–69. [WAM]Google Scholar
Hancock, P. A. & Newell, K. M. (1985) The movement speed-accuracy relationship in space-time. In: Motor behavior: Programming, control, and acquisition, ed. Heuer, H., Kleinbeck, U. & Schmidt, K. H.. Springer-Verlag. [aCLG]Google Scholar
Hannaford, B., Lakshminarayanan, V. & Stark, L. (1984) Electromyographic evidence of neurological controller signals with viscous load. Journal of Motor Behavior 16:255–74. [CR]Google Scholar
Hannaford, B. & Stark, L. (1985) Roles of the elements of the triphasic control signal. Experimental Neurology 90:619–34. [aGLG, CR]Google Scholar
Hannaford, B. (1987) Late agonist activation burst (PC) required for optimal head movement: A simulation study. Biological Cybernetics 57:321–30. [CR]Google Scholar
Hasan, Z. (1986) Optimized movement trajectories and joint stiffiacss in unperturbed, inertially loaded movements. Biological Cybernetics 53:373–82. [JPW]Google Scholar
Hasan, Z. & Enoka, R. M. (1985) Isometric torque-angle relationship and movement-related activity of human flexors: Implications for the equilibrium-point hypothesis. Experimental Brain Research 59:441–50. [aGLC]Google Scholar
Hasan, Z., Enoka, R. M. & Stuart, D. C. (1985) The interface between biomechanics and neurophysiology in the study of movement: Some recent approaches. Exercise and Sport Science Reviews 13:169234. [aGLC]Google Scholar
Hasan, Z. & Karst, G. M. (1987) Asynchronous initiation of coordinated rotations about the shoulder and elbow. Abstracts of the Society for Neuroscience 13:715. [GEL]Google Scholar
Hasan, Z. & Stuart, D. G. (1988) Animal solutions to problems of movement control: The role of proprioceptors. Annual Review of Neuroscience 11:199223. [SVA]Google Scholar
Henig, W., Favilla, M. & Ghez, C. (1988) Trajectory control in targeted force The nervous system, vol. 2: Motor control, part 2, ed. Brooks, V. B.. American Physiological Society. [aGLG]Google Scholar
Kelso, J. A. S. & Holt, K. C. (1980) Exploring a vibratory systems analysis of human movement production. Journal of Neurophysiology 43:1183- 96. [JASK]Google Scholar
Kelso, J. A. S. & Schöner, C. (1987) Toward a physical (synergetic) theory of biological coordination. springer Proceedings in Physics 19:224–37. [JASK]Google Scholar
Kelso, J. A. S., Schöner, C., Scholz, J. P. & Haken, H. (1987) Phase-pubnked modes, phase transitions, and component oscillators in biological motion. Physica Scripta 35:7987. [JASK]Google Scholar
Kelso, J. A. S. & Tuller, B. (1987) Intrinsic time in speech production: Theory, methodology, and preliminary observations, In: Sensory and motor processes in language, ed. Keller, E. & Copnik, M.. Erlbaum. [SAW]Google Scholar
Kerlinger, F. N. (1973) Foundations of behavioral research, 2nd edition. Holt, Rhinehart & Winston. [aCIC]Google Scholar
Knox, C. K. (1974) Cross-correlational functions for a neuronal model. Biophysical Journal 14:567–82. [aGLG]Google Scholar
Kornhuber, H. H. (1971) Motor functions of the cerebellum and basal ganglia: The cerebelpubnortical saccadic (ballistic) cpubnk, the cerebellomuclear hold regulator, and the basal ganglia ramp (voluntary speed smooth movement) generator. Kybernetik 8:157–62. [WAM]Google Scholar
Kots, Y. M. (1977) The organization of voluntary movement. Plenum. [aCLG]Google Scholar
Kugler, P. N. & Turvey, M. T. (1987) Information, natural law, and the self- assembly of rhythmic movement. Erlbaum. [KM N]Google Scholar
Kuo, B. C. (1987) Automatic control systems, 5th edition. Prentice Hall. [rGLC]Google Scholar
Kuypers, J. C. J. M. (1981) Anatomy of the descending pathways. In: Handbook of physiology. sec. 1: The nervous system, vol. 2: Motor control, part 1, ed. Brooks, V. B.. American Physiological Society. [JCH]Google Scholar
Laouris, Y. & Windhorst, U. (1989) The relationship between coherence and nonlinear characteristics in Renshaw cell responses to random motor axon stimulation. Neuroscience. [UW]Google Scholar
Lashley, K. S. (1917) The accuracy of movement in the absence of excitation from the moving organ. American Journal of Physiology 43 169–94. [aCLC]Google Scholar
Lashley, K. S. (1951) The problem of serial order in behavior. In: Cerebral mechanisms in behavior: The Hixon Symposium, ed. Jeffress, L. A.. Wiley. [aGLG]Google Scholar
Latash, M. L. & Gottlieb, C. L. (submitted) A model of dynamic regulation of fast single-joint movements: Emergence of reproducible EMG patterns. [MLL]Google Scholar
Lee, W. A. (1984) Neuromotor synergies as a basis for coordinating intentional action. Journal of Motor Behavior 16: 135–70. [SAW]Google Scholar
Lestienne, F. (1979) Effects of inertial load and velocity on the braking process of voluntary limb movements. Experimental Brain Research 35: 408–18. [aGLG, ZH, MLL, WAM]Google Scholar
Lestienne, F., Polit, A. & Bizzi, E. (1981) Functional organization of the motor process underlying the transition from movement to posture. Brain Research 230: 121–31. [JASK]Google Scholar
Loeb, G. E. (1985) Motoneurone task groups: Coping with kinematic hetrogeneity. Journal of Experimental Biology 115: 127–46. [CCAMG]Google Scholar
MacKenzie, C. L., Marteniuk, R. G., Dugas, C., Liske, D. & Eickemeter, B. (1987) Three-dimensional movement trajectories in Fills's task: Implications for control. Quarterly journal of Experimental Psychology 39A: 629–47. [aGLG]Google Scholar
Marsden, C. D., Obeso, J. A. & Rothwell, J. C. (1983) The function of the antagonist muscle during fast limb movements in man. Journal of Physiology (London) 335: 113. [aGLG, ZH, DSH]Google Scholar
Marsden, C. D., Rothwell, J. C. & Day, B. L. (1984) The use of peripheral feedback in the control of movement. Trends in Neuroscience 7: 253–57. [aGLG]Google Scholar
Matthews, P. B. C. (1959) The dependence of tension upon extension in the strength reflex of the soleus of the decerebrate cat. Journal of Physiology 47: 521–46. [MLL]Google Scholar
McCrea, D. A. (1986) Spinal cord circuitry and motor reflexes. Exercise and Sport Science Reviews 14: 105–42. [GEL]Google Scholar
McKay, W. A. (1988) Unit activity in the cerebellar nuclei related to arm reaching movements. Brain Research 442: 240–54. [WAM]Google Scholar
Meinck, H., Benecke, R., Meyer, W., Hohne, J. & Conrad, B. (1984) Human ballistic finger flexion: Uncoupling of the three-burst pattern. Experimental Brain Research 55: 127–33. [aGLG]Google Scholar
Meyer, D. E., Abrams, B. A., Koenblum, S., Wright, C. E. & Smith, J. E. K. (1988) Optimality in human motor performance: Ideal control of rapid aimed movements. Psychological Review 95: 340–70. [arGLG]Google Scholar
Meyer, D. E., Komblum, S., Abrams, B. A., Wright, C. E. & Smith, J. E. K. (1988) Optimality in human motor performance: Ideal control of rapid aimed movements. Psychological Review 95: 340–70. [CG]Google Scholar
Meyer, D. E., Smith, J. E. K. & Wright, C. E. (1982) Models for the speed and accuracy of aimed limb movements. Psychological Review 89: 449–82. [aGLG, SAW]Google Scholar
Milner, T. E. (1986) Controlling velocity in rapid movements. Journal of Motor Behavior 18: 147–61. [aGLG, BDB, JPW]Google Scholar
Moore, A. D. (1967) Synthesized EMG waves and their implications. American Journal of Physical Medicine 46: 1302–16. [aGLG]Google Scholar
Mustard, B. E. & Lee, R. G. (1987) Relationship between EMG patterns and kinematic properties for flexion movements at the human wrist. Experimental Brain Research 66: 247–56. [arGLG, ZH, DSH, MLL, JPW]Google Scholar
Nam, M. H., Lakshminarayanan, V. & Stark, L. W. (1984) Effect of external viscous load on head movement. IEEE Transactions on Biomedical Engineering BME-31: 303–9. [CR]Google Scholar
Nashner, L. M. & McCollum, G. (1985) The organization of human postural movements: A formal basis and experimental synthesis. Behavioral and Brain Sciences 8: 135–72. [PJC]Google Scholar
Neilson, P. D., Neilson, M. D. & O'Dwyer, N. J. (1988) Internal models and intermittency: A theoretical account of human tracking behavior. Biological Cybernetics 58: 101112. [PDN]CrossRefGoogle ScholarPubMed
Neisser, U. (1976) Cognition and reality. Freeman, W. H.. [rGLG]Google Scholar
Nelson, W. L. (1983) Physical principles for economies of skilled movements. Biological Cybernetics 46: 135–47. [aGLG]Google Scholar
Newell, K. M. (1986) Constraints on the development of coordination. In: Motor development in children: Aspects of coordination and control. ed. Wade, M. G. & Whiting, H. T. A.. Martinus Nijhoff. [KMN]Google Scholar
Newell, K. M. (in press) On task and theory specificity. Journal of Motor Behavior. [KMN]Google Scholar
Newell, K. M. & Carlton, L. C. (1988) Force variability in isometric responses. Journal of Experimental Psychology: Human Perception and Performance 14: 2436. [KMN]Google Scholar
Newell, K. M. & Hancock, P. A. (1984) Forgotten moments: A note on skewness and kurtosis as influential factors in inferences extrapolated from response distributions. Journal of Motor Behavior 16: 320–35. [rGLG]Google Scholar
Nimmo-Smith, I. (submitted) A visco-elastic approach to the organization of smooth movement. [JPW]Google Scholar
Norman, D. A. & Bobrow, D. C. (1975) On data-limited and resource-limited processes. Cognitive Psychology 7: 4464. [HH]Google Scholar
Norman, R. W. & Komi, P. V. (1979) Electromechanical delay in skeletal muscle under normal movement conditions. Acta Physiologica Scandinavica 106: 241–48. [aGLG]Google Scholar
Ogata, K. (1970) Modern control engineering. Prentice-Hall. [rGLG]Google Scholar
Patton, N. J. & Mortenson, O. A. (1971) An electromyographic study of reciprocal activity of muscles. Anatomical Record 170: 255–68. [rGLG]Google Scholar
Person, R. S. & Libkind, M. S. (1967) Modelling of interference myoelectric activity. Biofizika 12: 127–34 (English translation, 145–53). [aGLG]Google Scholar
Prochazka, A., Hulliger, M., Zangger, P. & Appenteng, K. (1985) “Fusimotor set”: New evidence for a-independent control of γ-motoneurones during movement in the awake cat. Brain Research 339: 136–40. [UW]Google Scholar
Pylyshyn, Z. W. (1980) Computation and cognition: Issues in the foundations of cognitive science. Behavioral and Brain Sciences 3: 111–69. [BDB]Google Scholar
Rack, P. M. H. & Westbury, D. B. (1969) The effects of length and stimulus rate on tension in the isometric cat soleus muscle. Journal of Physiology (London) 204: 443–60. [aGLG]Google Scholar
Ramos, C. F., Hacisalihzade, S. S. & Stark, L. W. (submitted) The behavior space of a stretch reflex model and its implications for the neural control of voluntary movements. [CR]Google Scholar
Ramos, C. F. & Stark, L. W. (1987) Simulation studies of descending and reflex control of fast movements. Journal of Motor Behavior 19: 3861. [CR]Google Scholar
Ramsey, R. W. & Street, S. F. (1940) The isometric length-tension diagram of isolated skeletal muscle fibers of the frog. Journal of Cellular and Comparative Physiology 15: 1134. [aGLG]Google Scholar
Robinson, D. A. (1970) Oculomotor Unit behaviour in the monkey. Journal of Neurophysiology 33: 393404. [EG]Google Scholar
Robinson, D. A. (1975) Oculomotor control signals in basic mechanisms of ocular motility and their clinical implications, ed. Lennerstrand, C. & Bach-y-Rita, P.. Pergamon. [CG]Google Scholar
Ross, H. G., Cleveland, S. & Kuschmierz, A. (1982) Dynamic properties of Renshaw cells: Equivalence of responses to step changes in recruitment and discharge frequency of motor axons. Pflügers Archiv 394: 239- 42. [UW]Google Scholar
Saltzman, E. & Kelso, J. A. S. (1987) Skilled actions: A task-dynamic approach. Psychological Review 94: 84106. [BDB]Google Scholar
Sanes, J. N. & Jennings, V. A. (1984) Centrally programmed patterns of muscle activity in voluntary motor behavior of humans. Experimental Brain Research 54: 2332. [aGLG, MLL]Google Scholar
Schmidt, B. A. (1975) A schema theory of discrete motor skill learning. Psychological Review 82: 1225–60. [aGLG, BDB]Google Scholar
Schmidt, R. A. (1976) The schema as a solution to some persistent problems in motor learning theory. In: Motor control: Issues and trends, ed. Stelmach, G. E.. Academic Press. [BDB]Google Scholar
Schmidt, H. A., Sherwood, D. E. & Walter, C. B. (1988) Rapid movements with reversals in direction. I: The control of movement time. Experimental Brain Research 69: 344–54. [arGLG, SAW]Google Scholar
Schmidt, R. A., Zelaznik, H. N., Hawkins, B., Frank, J. S. & Quinn, J. T. (1979) Motor output variability: A theory for the accuracy of rapid motor acts. Psychological Review 86: 415–51. [aGLG, SAW]Google Scholar
Schöner, C. & Kelso, J. A. S. (1988) Dynamic pattern generation in behavioral and neural systems. Science 239: 1513–20. [JASK]Google Scholar
Schwartz, A. B. & Georgopoulos, A. P. (1987) Relations between the amplitude of two-dimensional arm movements and single cell discharge in primate motor cortex. Society of Neuroscience Abstracts 13: 244. [TF]Google Scholar
Scudder, C. A. (1988) A new pubnal feedback model of the saccadic burst generator. Journal of Neurophysiology 59: 1455–75. [CCAMG]Google Scholar
Shapiro, D. C. & Walter, C. B. (1986) An examination of rapid positioning movements with spatiotemporal constraints. Journal of Motor Behavior 18: 372–95. [arGLC. DHH. SAW]Google Scholar
Sherwood, D. E., Schmidt, R. A. & Walter, C. B. (1988) Rapid movements with reversals in direction. II: Control of movement amplitude and inertial load. Experimental Brain Research 69: 355–67. [aGLG]Google Scholar
Sittig, A. C., Denier, van der Gon J. J. & Gielen, C. C. A. M. (1987) The contribution of afferent information on position and vepubnity to the control of slow and fast forearm movements. Experimental Brain Research 67: 3340. [CCAMG]Google Scholar
Sittig, A. C., Denier van der Gon, J. J., Gielen, C. C. A. M. & van, Wijk A. J. M. (1985) The attainment of target position during step-tracking movements despite a shift of initial position. Experimental Brain Research 60: 407–10. [CCAMG]Google Scholar
Soechting, J. F. (1984) Effect of target size on spatial and temporal characteristics of a pointing movement in man. Experimental Brain Research 54: 121–32. [TF]Google Scholar
Soechting, J. F. & Lacquaniti, F. (1981) Invariant characteristics of a pointing movement in man. Journal of Neuroscience 1: 710–20. [PJC]Google Scholar
Sparrow, W. A. (1983) The efficiency of skilled performance. Journal of Motor Behavior 15: 237–61. [aGLG]Google Scholar
Stark, L. & Bridgeman, B. (1983) Role of corollary discharge in space constancy. Perception & Psychophysics 34: 371–80. [BB]Google Scholar
Stein, R. B. (1982) What muscle variable(s) does the nervous system control in limb movements? Behavioral and Brain Sciences 5: 535–77. [aGLG, SVA, GEL].Google Scholar
Stein, R. B., Leung, K. V., Mangeron, D. & Oguztorelli, M. N. (1974) Impaired neuronal models for studying neural networks. Kybernetik 15: 19. [aGLG]Google Scholar
Stimpel, E. (1933) Der Wurf. Neue Psychologische Studien 9: 105–38. [HH]Google Scholar
Summers, J. J. (1988) Motor programs. In: Human skills (2nd ed.), ed. Holding, D. H.. Wiley. [BDB]Google Scholar
Summers, J. J., Bell, R. & Burns, B. D. (1989) Perceptual and motor factors in the imitation of simple temporal patterns. Psychological Research 51. [BDB]Google Scholar
Summers, J. J. & Burns, B. D. (1989) Timing in human movement sequences. In: Cognitive models of psychological time, ed. Block, R. A.. Erlbaum. [BDB]Google Scholar
Teulings, H. L., Thomassen, A. J. W. M. & Van, Galen C. P. (1986) Invariants in handwriting: The information contained in a motor program. In: Craphonoinics: Contemporary research in handwriting, ed. Kao, H. S. R., van Calen, C. P. & Hoosain, H.. North-Holland. [HLT]Google Scholar
Thomassen, A. J. W. M. & Teulings, H. L. (1985) Time, size, and shape in handwriting: Exploring spatio-temporal relationships at different levels. In: Time, mind, and behavior, ed. Michon, J. A. & Jackson, J. B.. Springer-Verlag. [HLT]Google Scholar
Turvey, M. T. & Kugler, P. N. (1984) An ecological approach to perception and action. In: Human motor action: Bernstein reassessed, ed. Whiting, H. T. A.. North-Holland. [KMN]Google Scholar
van, der Meulen J. H. P., Denier, van der Con J. J. & Cielen, C. C. A. M. (1988) Mechanisms underlying accuracy in fast goal-directed movements. In: Proceedings of the 7th Congress of the International Society of Electrophysiological Kinesiology. Elsevier. [CCAMC]Google Scholar
van, Gisbergen J. A. M., Robinson, D. A. & Cielen, S. (1981) A quantitative analysis of the generation of saccadic eye movements by burst neurons. Journal of Neurophysiology 45:417–42. [CCAMG]Google Scholar
van, Sonderen J. F., Denier, van der Con J. J. & Cielen, C. C. A. M. (1988) Conditions determining early modification of motor programmes in response to changes in target pubnation. Experimental Brain Research 71:320–28. [CCAMC]Google Scholar
Viviani, P. S. & Terzuolo, C. (1982) Trajectory determines movement dynamics. Neuroscience 7:431–37. [TF]Google Scholar
Wachholder, K. & Altenburger, H. (1926) Beitrage zur Physiologie der willkurlichen Bewegung. X: Mitteilung. Einzelbewegungen. Pflüigers Archiv für die gesamte physiologie des menschen unter der tiere 214:642–61. [aGLG]Google Scholar
Wadman, W. J., Denier, van der Con J. J. & Dersken, R. J. A. (1980) Muscle activation patterns for fast goal-directional arm movements. Journal of Human Movement Studies 6:1937. [TF]Google Scholar
Wadman, W. J., Denier, van der Con J. J., Geuze, H. H. & Mol, C. H. (1979) Control of fast goal-directed arm movements. Journal of Human Movement Studies 5:317. [aGLC, SVA, TF, MLL, JPW]Google Scholar
Wallace, S. A. (1981) An impulse-timing theory for reciprocal control of muscular activity in rapid, discrete movements. Journal of Motor Behavior 13:144–60. [aGLC, MLL, SAW]Google Scholar
Wallace, S. A. & Weeks, D. L. (1988) Temporal constraints in the control of prehensile movements. Journal of Motor Behavior 20:81105. [SAW]Google Scholar
Wallace, S. A. & Wright, L. (1982) Distance and movement effects on the timing of agonist and antagonist muscles: A test of the impulse-timing theory. Journal of Motor Behavior 14:341–52. [aCLG]Google Scholar
Wann, J. P. (1987) Trends in refinement and optimization of fine-motor trajectories: Observations from an analysis of the handwriting of primary school children. Journal of Motor Behavior 19:1337. [JPW]Google Scholar
Wann, J. P. (1988) The control of fine-motor trajectories. Doctoral thesis, Cambridge University. [JPW]Google Scholar
Wann, J. P., Nimmo-Smith, I. & Wing, A. M. (1988) Relation between vepubnity and curvature in movement: Equivalence and divergence between a power law and a minimum-jerk model. journal of Experimental Psychology: Human Perception and Performance 14:622–37. [JPW]Google Scholar
Waters, P. & Strick, P. L. (1981) Influence of “strategy” on muscle activity during ballistic movements. Brain Research 207:189–94. [arGLC, BOB, DSH]Google Scholar
Weiss, P. (1941) Self-differentiation of the basic patterns of coordination. Comparative Psychology Monographs 17(4). [DB]Google Scholar
Westbury, D. H. (1981) Electrophysiological characteristics of spinal gamma motoneurons in the cat. In: Muscle receptors and nwvement, ed. Taylor, A. & Prochazka, A.. Macmillan. [UW]Google Scholar
Wickelgren, W. A. (1977) Speed-accuracy tradeoff and information processing dynamics. Acta Psychologica 41:6785. [HH]Google Scholar
Windhorst, U. (1988) How brain-like is the spinal cord? Interacting cell assemblies in the nervous system. Springer-verlag,. [UW]Google Scholar
Windhorst, U. & Koehler, W. (1983) Dynamic behaviour of a-motoneurone sub-pools subjected to inhomogeneous Renshaw cell inhibition. Biological Cybernetics 46:217–28. [UW]Google Scholar
Windhorst, U. & Koehler, W. (1986) The dynamic effects of inputs to spinal motoneurones of different type upon the outputs of y-motoneurones mediated via recurrent inhibition. Biological Cybernetics 54:167–77. [UW]Google Scholar
Wright, C. E. & Meyer, D. E. (1983) Conditions for a linear speed-accuracy trade-off in aimed movements. Quarterly Journal of Experimental Psychology 35A:279–96. [aGLG, DHH]Google Scholar
Zajac, F. E. & Gordon, M. E. (1989) Determining muscle's force and action in multi-articular movements. Exercise and Sport Science Reviews 17:187230. [GEL]Google Scholar
Zelaznik, H. N., Schmidt, B. A. & Gielen, S. C. A. M. (1986) Kinematic properties of rapid aimed hand movements. Journal of Motor Behavior 18:353–72. [aGLG]Google Scholar