Motor_Control___Learning

154 IV. DEVELOPMENT AND AGING that help alleviate the detrimental effects (DeVita and Acknowledgments Hortobagyi 2000; Shinohara et al. 2003a). This study was supported in part by NIH grants However, the finding of disproportional losses of AG-018751, NS-035032, AR-048563, and M01 force at the two sites, PP and DP, suggests poten- RR10732. We are grateful to Ning Kang, Brendan tially detrimental effects on muscle synergies involved Lay, and Sheng Li for their help in performing the ex- in finger force production. Most everyday tasks in- periments at different stages of this project, to the per- volve force application by the fingertips. These forces sonnel of the General Clinical Research Center at The generate moments in finger joints that need to be bal- Pennsylvania State University for screening the sub- anced by muscle action. In particular, intrinsic muscles jects, and to the staff and participants at the Foxdale are required to balance moments in the MCP joints. Village (State College, PA) for their cooperation. Hence, commands to extrinsic and intrinsic muscles need to be accurately balanced to prevent joint motion References under fingertip force production. Such combinations of commands are probably elaborated and refined by An KN, Kwak, BM, Chao EY, Morrey BF (1984) Deter- the central nervous system (CNS) based on the in- mination of muscle and joint forces: a new technique to dividual person’s anatomy and the range of everyday solve the indeterminate problem. J Biomech Eng, 106: tasks. 364–367. If the force-generating capabilities of muscles in- Arimoto S, Nguyen PTA (2001) Principle of superposi- volved in a synergy change disproportionately, previ- tion for realising dexterous pinching motions of a pair ously elaborated combinations of neural commands of robot fingers with soft-tips. IEICE Trans Fundament to the muscles are likely to become suboptimal. If Elec Comm Comp Sci E84A: 39–47. such changes in the muscle properties are permanent, as with aging, previously elaborated muscle synergies Arimoto S, Tahara K, Yamaguchi M, Nguyen PTA, Han likely need to be adjusted. This may not be a simple HY (2001) Principles of superposition for controlling task for the CNS resulting in the application of inad- pinch motions by means of robot fingers with soft tips. equate muscle synergies and decreased motor perfor- Robotica 19: 21–28. mance of the hand (Connelly et al. 1999; Grabiner and Enoka 1995; Shinohara et al. 2003a). Atkeson CG (1989) Learning arm kinematics and dynamics. Ann Rev Neurosci 12: 157–183. One may suggest two ways of dealing with this problem. First, massive practice may help the CNS Basmajian JV, De Luca CJ (1985) Muscles Alive, 5th ed. revise the inadequate muscle synergies and elaborate Williams & Wilkins, Baltimore. new ones. However, the continuing changes in the muscle properties with age may prevent the CNS Baud-Bovy G, Soechting JF (2001) Two virtual fingers in from elaborating new optimal sets of commands to the control of the tripod grasp. J Neurophysiol 86: 604– hand muscles. Alternatively, efforts can be directed at 615. restoring the balance between the force-generating ca- pabilities of the intrinsic and extrinsic muscles. This Baud-Bovy G, Soechting JF (2002) Factors influencing vari- goal may be more realistic with the help of specifically ability in load forces in a tripod grasp. Exp Brain Res 143: focused training programs. 57–66. Effects of training have been documented in many Bemben MG. Age-related alterations in muscular en- studies of elderly subjects. In particular, training has durance. Sports Med 25: 259–269, 1998. been shown to lead to higher forces and lower antag- onist coactivation. 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AUTHOR INDEX A Bickerton LE, 143 Abbott T, 56 Bigland-Ritchie BR, 153 Abbs JH, 149 Binder-McLeod SA, 153 Abend W, 21 Biscoe TJ, 116, 121 Albus JA, viii, 106, 108 Bizzi E, 21, 98, 135 Alexander RM, 15 Blatt GJ, 116, 121 Alexandrov AV, 42 Boatright JR, 145 Amazeen EL, 78 Bo¨ck O, 81, 86 Amblard B, 133 Bootsma R, 77 An KN, 143 Borghese NA, 129 Andre-Thomas, 29 Bouisset S, vii, 28–32, 34, 37, 41 Ansved T, 146 Bracewell RM, 52 Arbib MA, 105 Breniere Y, 133 Arimoto S, 150 Brenner E, 23 Armstrong DM, 98 Bril B, 133 Aruin AS, 42 Brashers-Krug T, 92 Asanuma H, 98, 100 Browman CP, 66, 68, 69, 70 Asatryan DG, 5, 6, 20 Brown WF, 145 Aschersleben G, 50, 51 BÅhler M, 55, 57 Assaiante C, 133 Bullock D, 66 Athenes S, 10, 11 Bunz H, 48, 68, 78 Atkeson CG, 20, 58 Burke R, 51 Burnett RA, 152, 153 B Burnod Y, 105 Bailly G, 66, 67 Burstedt MK, 150 Baker SM, 98 Byrd D, vii, 65, 66, 68, 70, 72 Balasubramaniam R, vii, 47–50, 52, 79 Baraduk P, 106, 112 C Baranyi A, 108 Caddy KWT, 116, 121 Bardy BG, viii, 77, 78, 81–83, 86 Caldwell, 13, 14 Barin K, 79 Caminiti R, 98, 101 Barnes HG, 11, 12, 18–20 Campbell MJ, 153 Basmajian JV, 142 Capaday C, 98 Baud-Bovy G, 150 Carello C, 10 Beckers MC, 116 Carlso¨o¨ S, 28 Beek PJ, 48, 52, 56, 81 Carson RG, 50, 52, 81 Bembem MG, 145 Caston J, 117 Bengoetxea A, viii Cavagna GA, 133 Bennet-Clark HC, 15 Cavanaugh P, 149 Bennett KM, 98 Cebolla A, viii Berger W, 133 Chao EY, 142 Bernstein NA, vii, 40, 86, 128, 141 Chaput S, 144 Bianchi L, 129, 131–133 Cheney PD, 59, 97, 98, 100, 101 161

162 AUTHOR INDEX Cheng S-W, 116 Dufosse M, viii, 108, 112 Cheron G, viii, 128, 129, 130, 131, 132, 133, 134, 135, Dugas C, 10, 11 136 E Christ CB, 147 Eccles J, 146 Cioni G, 133 Edelman GM, 135 Clark JE, 133 Edin BB, 150 Clifton RK, 10 Eisenman LM, 116, 121 Cohen RG, vii, 16–18, 21 Eliasson AC, 150 Coker CH, 66 Enoka RM, 152, 153, 154 Cole KJ, 144, 145, 149, 150, 152, 153 Era P, 147, 153 Colter JD, 97 Evarts EV, 97, 98, 101 Conditt MA, 135 Connelly DM, 154 F Conner JM, 90 Farley CT, 80 Contreras-Vidal JL, 145, 153 Farmer JD, 64 Cooke DW, 98, 101, 133, 144 Faugloire E, viii, 81, 85, 86 Cooper S, 146 Feher, 108 Corcos DM, 29, 41 Feldman AG, vii, viii, 3–7, 20, 21, 106, 135 Cordo PJ, 30 Fetz CE, 50, 97, 98 Courville J, 112 Flanagan JR, 21, 28, 150 Cowan WM, 116 Flash T, 49, 112 Crepel F, 108 Fleckenstein JL, 143 Foerster O, 97 D Fontaine RJ, 81, 86 D’Arcangelo G, 116 Forssberg H, 127, 133 Daffertshofer A, 48, 52 Fourcade P, viii, 81 Dan B, viii, 133 Francis PR, 145, 153 Daniel H, 108 Fraser, 10 Danion F, 142, 143, 144, 146 Friedli WG, 29 Darling WG, 142, 144 Friston KG, 90 Das P, 128 Frolov AA, viii, 106, 112 Dawson A, 21 Fulton JF, 97 Deiss V, 118, 121 Delcolle, 48 G Deliagina T, 127 Gachoud JP, 23 Delignieres D, 49 Galganski ME, 145, 153 Delong MR, 51 Gandevia SC, 51, 142 De Ko¨ning JJ, 28 Garrett WE Jr, 145 DeLuca CJ, 142 Gatter KC, 98 Dempster WT, 28, 39 Gaudez C, 40 Denny Brown DE, 145 Gaughran GRL, 28, 39 De Rugy A, 56, 60 Gelfand IM, 41, 142 DeVita P, 154 Georgopoulos AP, 98, 101, 107, 108 De Vries JIP, 133 Ghafouri M, 7 De Zeeuw CL, 112 Ghez C, 20, 29, 41 Diedrichsen J, 49 Ghilardi MF, 20 Dietz V, 133 Ghosh S, 98 Dijkstra TMH, 56–59, 79 Giampaoli S, 145 Dmitrijevic M, 127 Gibson JJ, 10 Dimov M, 6 Gielen CCAM, 79 Doherty TJ, 145 Gilbert PFC, 108, 112 Donoghue JP, 97 Gilles MA, 153 Doya K, 133 Goffinet AM, 116 Doyon J, 92 Goldstein L, vii, 66, 68, 69, 70 Draye JP, 133 Golub GH, 109 Drew T, 98 Gonzalez-Lima, F 118 Drewing, 51 Goodale MA, 10 Duarte M, 56 Gordon J, 20, 29, 41 Duchateau J, 145

AUTHOR INDEX 163 Gottlieb GL, 135 Ito M, viii, 106, 108, 111, 112 Gould HJ 3rd, 97 Ivry RB, 49 Grabiner MD, 145, 154 Gracco VL, 66 J Grafton ST, 90, 92 Jaillard D, 108 Grasso R, 129, 133 Jankowska E, 97, 98 Graziano MSA, viii, 20, 98, 100, 101 Jansen C, 10, 20, 21, 22, 23 Gribble PL, 4, 66, 106, 135 Jeannerod M, 10, 11, 21 Grieve DW, 28, 30, 40 Jenkins IH, 90 Grill S, 51 Jensen JL, 133 Grillner S, 127 Jeneson JA, 143 Grimby G, 145 Johansson RS, 28, 39, 42, 150 Gross CG, 101 Jones EG, 98 Grossberg S, 66 Jones D, 118 Guastavino G-M, 116, 118 Jordan MI, 66, 67, 98, 106 Guckenheimer J, 56 Jorgensen MJ, 11, 12, 15, 16, 18–21 Gunther M, 6 K H Kakei S, 98, 101 Hack I, 116 Kalaska JF, 98, 101 Hackel ME, 145 Kalil K, 98 Hadders-Algra M, 128, 133 Kamen G, 145, 153 Hager-Ross C, 150 Kang Y, 98 Hainaut K, 145 Karni A, 90 Hallett M, viii, 51 Kashiwabuchi N, 116 Haken H, 48, 68, 78 Katsumata H, 56 Hakkinen K, 154 Kawato M, 22, 106, 111, 112, 133 Hamilton BA, 116 Kay BA, 50, 79 Hammar I, 98 Kearney RE, 80 Harding DC, 143, 153 Kelso JAS, 47, 48, 50, 52, 67, 68, 78, 81, 83, 86, 133 Harris CM, 53 Kenshalo DR, 145, 152 Hauert CA, 23 Kernell D, 145 He SQ, 97, 101 Kilbreath SL, 142 Heckroth JA, 116, 121 Kindlmann PJ, 55 Heinz N, 116 Kinoshita H, 142, 145, 153 Hermsdorfer J, 150 Kirkendall DT, 145 Herrup K, 116 Kitazawa S, 112 Hibbard LS, 97 Klatzky RL, 21 Hirschfeld H, 127, 133 Klein C, 112 Hogan N, 21, 49, 112 Kleweno DG, 14 Holcombe HH, 93 Kluin KK, 122 Holderfer RN, 97, 101 Koditschek DE, 55, 57 Hollerbach JM, 3, 20 Koike Y, 133 Holmes P, 56 Koppell N, 128, 131 Honda M, 91, 93 Koozekanani SH, 79 Horak FB, 41 Kremarik P, 117, 118, 121 Hornik K, 133 Kristofferson AB, 48, 50 Hortobagyi, T 154 Kroemer KHB, 28, 40 Huang GB, 65 Kro¨ger B, 66 Huang CH, 112 Kuang RZ, 98 Hughes S, 145 Kumamoto M, 133 Hunter IW, 80 Kuo AD, 79 Huntley GW, 98 Kuperstein, M 106 Kwan HC, 97, 98 I Iberall T, 150 L Ikeda ER, 149 Laboissiere R, 66, 67 Inhoff AW, 112 Laidlaw DH, 147 Iriki A, 90, 108 Lalonde R, viii, 115–118, 121, 122

164 AUTHOR INDEX Lalouette A, 116, 118 Miller AE, 153 Lacquaniti F, 21, 41 Miller LE, 97, 101 Landgren S, 97 Milner AD, 10 Landis DMD, 116 Mitnitski AB, 21 Landry P, 98 Mitra S, 67 Landsend AS, 115 Mittelstaedt H, 5 Landsmeer JM, 142, 143 Moore T, 20 Lanshammar H, 28 Morgenroth DC, 80 Larsson L, 146 Morrow MM, 97 Lasko-McCarthey P, 133 Mounoud P, 23 Latash ML, viii, 4, 5, 42, 141–144, 148, Morasso P, 21 Muellbacher W, 93 152 Mullen RJ, 116 Lathroum A, 66 MÅller H, 60 Le Bozec S, vii, 28, 32, 33, 37, 41 Munhall KG, 64–66 Le Veau B, 80 Murray EA, 97 Leavitt JL, 10 Mussa Ivaldi, FA 135, 141 Ledebt A, 133 Lee TD, 81, 86 N Lee WA, 30 Nagasaki H, 49 Leijsne JL, 142 Nakagawa S, 116 Leiner HC, 112 Nakano E, 112 Lemon RM, 97, 98, 101 Nakao M, 145 Leonard CT, 133 Nam H, vii, 68 Lestienne F, 6 Nashner LM, 30, 79 Leurs F, viii Newell KM, 86, 145 Levin MF, 6, 7 Nigg BM, 28, 80 Li S, 143, 146 Li Z-M, 141, 142, 143 O Liepert, 89 Ohtsuki, T 142 Lino F, 31, 37, 39 Okamoto, T 133 Litovsky, RY10 Olivier E, 97 Lo¨fqvist A, 67 Opgen-Rhein C, 66 Long C, 142, 143 Ostry DJ, 3–6, 66 Oullier O, 78 M Owings TM, 144 Mackenzie CL, 10, 11, 150 Oyama E, 106 MacMahon TA, 15 Macpherson JM, 40 P Maier MA, 97 Pagulayan RJ, 77 Maioli C, 41 Pananceau M, 108 Mano NL, 112 Park MC, 97 Marchak F, 11 Pascual-Leone A, 89, 90, 91 Mariani J, 116 Patton JL, 30 Marin L, 77, 78, 83 Penfield W, 142 Marr D, viii, 21, 22, 106, 108 Penhune V, 92 Marteniuk RG, 10, 11 Perris EE, 10 Matsuda S, 116 Phillips SJ, 133 Matsumura M, 98 Pigeon P, 21 Matthews PBC, 51 Porter R, 98 McCollum G, 79, 128 Prablanc C, 14 McDermott LR, 153 Pratt J, 144 McDonaugh MJ, 145 Pressing J, 51 McIntyre J, 135 Prilutsky BI, 142 McKiernan BJ, 97 Prinz W, 50, 51 Meckler C, 14 Proteau L, 144 Mefta EM, 108 Merhi O, 86 Q Meulenbroek RGJ, vii, 10, 20–23 Quartz SR, 65 Mewes K, 50

AUTHOR INDEX 165 R Sim M, 56 Raibert M, 56 Slotta J, 11 Rantanen T, 145 Smeets JBJ, 23 Rasmussen T, 142 Soechting JF, 21, 149, 150 Reilly J, 56 Smart LJ, 77 Reina GA, 98, 101 Smethurst CJ, 81 Repp BH, 48 Smith LB, 131 Resibois A, 116 Smith RJ, 143 Rho MJ, 98 Smyth MM, 21 Ribrean C, vii Sotelo C, 116 Riek P, 50 Spencer RM, 49, 52 Riley MA, 48, 79 Spiegel KM, 145 Rispal-Padel L, 108 Spirduso WW, 145 Rizek, 106, 112 Sporns O, 135 Rochat P, 10 St-Onge N, 6 Roffler-Tarlov S, 116 Steinmayr M, 116 Roland PE, 90 Stelmach GE, 144 Rosenbaum DA, vii, 10–23, 142 Stephanishin DJ, 80 Rosenthal G, 122 Sternad D, vii, 47, 56–58, 60, 78 Rossetti Y, 14 Stevens LT, 48 Rotella, 145, 149 Stockwell CW, 79 Roudeix S, 81 Stoffregen TA, viii, 77, 81, 86 Roullier EM, 142 Strandberg L, 28, 39 Ruder H, 6 Strazielle C, viii, 115–118, 121 Rumelhart DE, 106 Sundararajan N, 65 Sutherland DH, 133 S Swinnen SP, 48, 81 Saint-Cyr JA, 112 Saltzman EL, vii, 64, 65, 66, 67, 68 T Sanes JN, 97, 98 Taga G, 79 Santello M, 149, 150 Tantisira B, 98 Saratchandran, P 65 Taylor CSR, 20, 101 Sashihara S, 121 Terashima T, 116 Schaal S, 58 Thach WT, 108, 112 Schieber MH, 97, 142, 143 Thelen E, 128, 131, 133 Schlaug G, 90 Thomas CK, 146 Schneider K, 97, 98, 128 Thullier F, 116 Scholz JP, 144 Tisserand M, 28 Scho¨ner G, 47, 48, 79, 131, 142 Todorov E, 98 Schro¨der G, 66 Trommsdorff M, 116 Schwartz JL, 66, 67 Tsetlin ML, 142 Schweighofer, N 108 Tufillaro NB, 56 Scott SH, 98, 101 Tuite DJ, 145 Seidler RD, 92, 144 Tuller B, 67, 128 Seitz RG, 90 Turner RS, 51 Sejnowski TJ, 65 Turton A, 10 Selimi F, 116 Turvey MT, 10, 47, 48, 56, 78, 79, 141 Semjen A, 47 Semmler JG, 147 U Sergio LE, 98, 101 Uno Y, 112 Serlin DM, 143 Shadmehr R, 93 V Shannon C, 56 Vaillancourt DE, 145 Shaw RE, 56 Vaughn J, vii, 10, 11, 12, 18–23 Shim JK, viii, 144, 148, 150–152 Viviani P, 23 Shinoda Y, 98 Vallbo AB, 50 Shinohara M, viii, 145–149, 151, 152, 154 Van Heughten, C 14 Shojaeian H, 116, 121 Van Ingen Schenau GJ, 28 Sidman RL, 116 Van Loan CF, 109

166 AUTHOR INDEX Van Santvoord AAM, 56 Winegard KJ, 145 Vandervael F, 37 Winter DA, 79, 80 Verschueren S, 81 Winters JM, 14, 135 Viitasalo JT, 145, 147 Wolpert DM, 21, 53, 111 Von Holst E, 5 Wong-Riley MTT, 118, 122 Vogel MW, 116 Woollacott MH, 133, 144 Vogt S, 21, 22 Vorberg D, 47, 48, 50, 51 Y Yahia LH, 21 W Yang JF, 79, 133 Wachs J, 90 Yu H, 47 Wallace SA, 10 Yue GH, 50 Wann JP, 49 Yuzaki M, 116 Warren W, 79 Weeks DL, 10, 150 Z Wei K, 60 Zajac FE, 134, 135 Weiss PL, 80 Zanger TE, 127 Welford AT, 144 Zanone PG, 81, 83, 86 Wells RP, 79 Zatsiorsky VM, viii, 142, 149, 150, Wenderoth N, 81, 86 Wessberg J, 50 153 Westling G, 28, 39, 42 Zattara M, 29, 34, 37 Whitney RJ, 28, 30 Zelaznik HN, 49 Wing AM, 10, 28, 42, 47, 48, 50–52, 150, 153 Zimmerman SD, 146 Zuo J, 115

SUBJECT INDEX A Learning, 105, 106, 107 Affordances, 10 Marr-Albus-Ito theory, 105, 106 Aging effects, viii, 141–154 Metabolism, 118, 119, 120 Parallel fibers, 105, 108, 110 Accuracy, 144 Plasticity, 105–112 Force variability, 145, 153 Purkinje cells, 105, 107, 108, 110, 116, 118, Innervation ratio, 146 Kinematics, 144 119 Motor units, 145 Role in mental skills, 112 Muscles, 145, 153 Role in serial movements, 112 Safety margins, 144, 153 -thalamo-cortical projections, 105, 107, 108, 110 Sensory function, 145 Coactivation, 6 Time pressure effects, 144 Coordinate systems, 109 Training effects, 154 Coordination, 128 Alpha-motoneurons, 107 Bimanual, viii, 78, 86 Age changes, 144, 145 Dynamics, 86 Alzheimer’s disease, 91 Intersegmental, 131 Anticipatory postural adjustments, 32, 35, 42 Muscle, 134 Development, 133 Postural, 77 Apraxia, 92 Cortex, viii Ataxia Motor, 89–94, 97–102, 117 Spinocerebellar, 122 Parietal, 92, 107 Attractors, 81 Piriform, 121 Limit cycle, 48, 52, 67, 68 Prefrontal, 93 Neural hypothesis, 131 Primary, 20 Point, 48 Primary somatosensory, 121 Premotor, 20, 92, 93 B Corticospinal tract, 89 Balance, 121, 122, 127 Critical fluctuations, 78, 81 Ball bouncing, 55–62 Basal ganglia, 92, 93 D Biomechanics Damping, 52, 64, 79 Degrees-of-freedom, 128, 135, 141, 143, 149 Adherence, 28, 39, 40 Dimensionality, 64, 108, 128 Finger action, 149, 150 Divergence, 98 Friction, 28, 37, 39, 42 Dynamic systems, vii, 47, 48, 63–71, 133 Modeling, vii, 30, 31, 32, 33 Coupling, 134 C Mapping, 135 Center of pressure, 41 Dynamics, 128 Center of gravity, 41, 127 Coordination, 135 Central pattern generator, 127, 128 Graph, 63–72 Cerebellum, viii, 49, 92, 115–122 Nonlinear, 77 Parameter, 63–72 Atrophy, 115–122 Sensorimotor, 135 Cytochrome oxydase activity, 117 State, 63–72 Degeneration, 91 Stochastic, 79 Granule cells, 116, 118, 119 167

168 SUBJECT INDEX E K EEG (electroencephalography), viii, 89 Kinematics, 66, 128 Coherence 89 Parallel chains, 141 EMG (electromyography), viii, 3, 6, 128, 129, Serial chains, 141 133–137 L Elasticity, 14, 15 Lambda-model, 6 Equilibrium, 4, 128 Locomotion, viii, 121, 122 Dynamic, 55, 128, 133 Development, 127–137 State, 108 Long-term depression (LTD), 108 Equilibrium-point, 48 Long-term potentiation (LTP), 90, 108 Hypothesis, vii, 20, 106, 107, 112 M F Mass-spring model, 64 Feedback, 98, 133 Motor cortex, 89–94, 97–102 Proprioceptive, 98, 99, 101 Body part representations, 89, 97 Feed-forward Lateral connections, 98 Plasticity, 105–112 Control, 42, 64, 133 Projections on alpha-motoneurons, 89 Modeling, 21 Remapping, 97–102 Finger coordination, viii, 141–154 Motor coordination, 116, 117 Changes with age, 145 Motor development, viii, 116, 127–137 Finger interaction, 142, 143 Of posture, 127, 128 Changes with age, 143, 146, 147 Of sitting, 128 Gender effects, 146 Motor equivalence, 86 Force control, 3 Motor learning, viii, 63, 77–86, 89–94, 105–112, 133 Forward model, 106 Babbling, 108, 109 Frames of reference (coordinate systems), 7, 30, Cerebral-cerebellar, 105–112 Consolidation, 89, 92 40 Dynamical theory, 81 Functional magnetic resonance imaging (fMRI), Error back propagation, 106 Error curve, 134, 135 90 Explicit, 91, 92 Hebbian, 106, 108, 109 G Implicit, 92 Grasping, viii, 12, 13, 21, 22, 141 Supervised, 109 Grip Motor planning, vii, 10, 18, 19, 20, 22, 40 Motor redundancy, vii, 6, 141, 142 Overhand, 11, 16 Motor skill, 63 Underhand, 11, 16 Multi-joint movements, viii Mutations, 115–122 H Hand N Neural Function, 141–154 changes with age, 145 Networks, 64, 105, 106, 128, 133–137 Plasticity, 77–86 Muscles, viii Nuclei extrinsic, 142, 143, 146 Cerebellar, 117, 120, 121 intrinsic, 142, 143, 146 Dorsal raphe, 117, 121 Magnocellular, red 121 Head control, 133 Pontine, 117, 121 Hierarchical control, 21, 48 Vestibular, 117 Huntington’s disease, 91 Hysteresis, 15, 78, 81 O Optimization, 142 I Inferior olives, 106, 112, 116, 117, 121 End-state comfort, 10–12 Mechanical energy, 132, 133 Climbing fibers, 106, 108, 112 Minimum jerk, 49, 50, 52, 112 Information processing, 47, 48 Minimum torque change, 112 Inverse model, 106, 111, 112 Inverted pendulum, 79 J Jacobian, 106, 112 Pseudo-inverse, 106, 111 Juggling, 56, 57

SUBJECT INDEX 169 Oscillators, 67, 68 Spasticity, 133 Coupled, 68, 69, 128 Speech, viii, 65–71 Mechanical, 133 Spike triggered averaging, 98, 100 Neural, 133 Spinal cord, 98 Stability, vii, 48, 50, 55–60, 70, 82 P Parkinson’s disease, 91, 133 Lyapunov, 58, 59 PET (positron emission tomography), viii, 89, 91 Passive, 56, 57, 58 Perception Stiffness, 52, 79 Supplementary motor area, 92 -action coupling, 55 Sway, 131 Auditory, 10 Synaptic plasticity, 106, 108 Haptic, 10, 42 Synergetics, 128 Visual, 61 Synergy, 143, 144, 148, 149 Phase transitions, 78, 83 Changes with age, 151, 153 Plasticity, viii, 105–112 Pointing, 29 T Postural control, vii, 27–45, 77 Tapping, 143 Posture (postural) TMS (transcranial magnetic stimulation), viii, 89, 91, Chain, 29, 30, 33, 35, 37, 40, 41 -kinetic capacity, 34 143 Modes, 78, 84 Trajectory -movement problem, 4 Sitting, 29 Virtual, 106 Stability, 77, 83–85, 128 Transcranial direct current stimulation (TDC), 92 Prehension, 9, 10, 21, 142 Transformation Synergies, 148, 149 Principle Motor-visual, 112 of abundance, 142 Sensorimotor, 107 of minimal interaction, 6 Visuo-motor, 106, 107, 108, 109, 112 of superposition, 150 Thalamus, viii, 105–112, 117, 121 Progressive supranuclear palsy, 91 Threshold control, 4, 5 Pronation/supination, 148 Thumb, 150 Proprioceptive feedback, viii, 106 Timing, 47 Role in timing, 51, 52 In musical performance, 47 Pyramidal tract, 97, 107 In rhythmic action, 47 Role of the cerebellum, 49, 52 R Synchronization, 50 Reaching, 105, 107, 108 Syncopation, 50 Red nucleus, 117, 1221 Wing-Kristofferson model, 48–53 Redundancy, 106, 111, 112, 128 Trajectory formation, 49 Reflex U Stepping, 128 Uncontrolled manifold hypothesis, 142, 143, 144, 148 Relative phase, 68, 69, 70, 71, 80, 81 Representations, 135 V Rhythmic actions, vii, 55–62 Variability, 58–60, 70–72, 128 Robotics, 9, 55, 57 Force, 145 S Timing, 48 Self-organization, 81 Variables Singular value decomposition, 109 Control, 3, 4, 41 Elemental, 143, 148, 149, 150 Performance, 143, 148, 150 State, 3, 4