Motor Control & Sensory Integration

Limiting Motions in Prehension 401 4.1. Method A single subject was tested using a method similar to that of Experiment 1. A metal prism (height 65mm, width 64mm, depth 5mm) was rigidly mounted on a board. Marking stripes were attached to the board at 384, 192, 96, 48, 24, and 12 mm from this object. The subject was seated in front of the horizontal board with the fingers and thumb lightly closed touching one of the marking strips, directly in front of the target. The subject was instructed to move as fast and accurately as possible to grasp the object between thumb and forefinger. The 6 amplitude conditions were presented in order longest to shortest. Practice trials, and 6 recorded trials were conducted for each condition. Three reflective markers (diameter 5mm) were attached to bony landmarks (ulnar styloid process, nail of thumb and finger) and the movements were videotaped at 50Hz by a camera situated vertically above the centre of the movement path with the lens horizontal. The positions of the markers in each frame were manually digitised using commercially available software (PEAK Performance Technologies Inc.) 4.2. Results Displacement of the wrist marker in the direction of transport, and the distance between the thumb and finger markers (aperture) were plotted for each trial. A representative plot for each condition is presented in Figure 8. Inspection of the data showed that while wrist displacement was consistently toward the object for amplitudes 384, 192, 96, and 48mm, for amplitudes of 24 and 12mm this component of the wrist movement was initially in the opposite direction, before it subsequently reversed and began moving toward the object. The maximum displacement away from the target and the duration of this displacement increased with decreasing distance of the target from the starting position of the hand. 4.3. Discussion Inspection of some kinematic parameters of movement of the wrist and fingers of a single subject reaching to grasp a stationary object placed close to the hand supported the finding that movement times increase when the object is less than 25mm from the hand. The initial movement of the wrist away from the target may have effectively lengthened the transport time to enable concurrent preshape formation and object

402 P.J. Bate & E.R. Hoffman Dlsplscement (mm) Displacement (ram) \" 400 26~I Amplitude - 192 mm 300 2ooITarget width - 200 100 .o I ......................................... .................................................... .o I ................../........ ................................ 60~ ................................................................................................ 100 200 300 400 0 Time (ms) 0 60 100 160 200 260 300 360 400 Wrist Poeltlon ~ Flngm opening Time (ms) Wrist Poeltloa ~ Finger opening Displacement (ram) Displacement (ram) 16o / 16o 6o~/ .Amplitude - 96 mm 1oo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Target width - 64 mm 60 ....................................................................................................... o, t t / / T~rgetwidtGh,-m, 0 60 100 160 ~ 260 o ~a,~--.-,.~ | , i L i ! Time (ms) 0 ' 60 100 160 200 260 300 360 400 Time (mS) wrist Poeltion -;'- Finger opening Wwlet Position ~ FlngqNropening Otsplscement (ram) Displacement (ram) 160 160 100 100 ................................................................................... 80 60 0 \"S~ o0 loo mo eoo x o \"600 ao m ~o 2o0 eso aoo aeo 1nine (me) Tlme (me) Wrlet PoelUom -4-- FlngM (q)e~ning ~ Wrlet P~ltloa --~ Finger opening Figure 8. Wrist displacement in the direction of wansport and hand ~ for a single subject at six movement amplitudes.

Limiting Motions in Prehension 403 enclosure by the hand, as proposed by Hoff and Arbib (1993). It is likely u~at the backward movement of the wrist enabled the forward motion of the fingertips which is concommittant with widening the aperture, to occur without the fingers touching the object, as is implicit in the instruction \"fast and accurate\". 5. GENERAL DISCUSSION These experiments supported the constant enclosure model of the relationship between transport and grasp components of prehension proposed by Hoff and Arbib (1993). When the movement amplitudes were greater than about 90 mm, transport time was linearly related to the square root of movement amplitude and little affected by object width. In terms of the model, transport was the limiting motion. However, when amplitude was less than 25mm, transport time increased, as predicted by the model, and increased with object width. Interpreting this in terms of the Hoff and Arbib (1993) model, time to pre-shape plus enclosure time became the limiting motion of the task. The finding that object depth had an effect on the duration of the transport component of a reach and grasp task was consistent with a report of movement times to objects of sizes in the range tested in the present experiments (Marteniuk et al., 1990). Because the objects used by Marteniuk et al (1990) were cylindrical, it was possible to re-interpret Marteniuk et al.'s (1990) result in the light of the present findings, as an effect of object depth (in the direction of movement) on movement time, rather than an effect of object width. The effect was most apparent for small values of target depth (less than 30 mm). It conflicts with findings of no effect of the width/depth of cylindrical objects of similar sizes on movement times reported by Wallace and Weeks (1988) and Paulignan et al (1991). This effect of depth on movement time is generally small, appearing to be of the order of 60 ms in the Marteniuk et a1.(1990) data and 25 ms in the present data set. There is a major difference in experimental paradigm which offers a possible explanation for the smaller size of the effect in the presenr data set. Subjects in the present study moved to grasp a fixed object, but the subjects of Marteniuk et al. (1990) lifted an object and replaced it on a table. This requirement may have enhanced the precision content of the Marteniuk et al. (1990) task and thus increased movement times for smaller objects. This explanation is consistent with Wallace and Weeks' (1988) failure to identify an effect of object size on movement time when subjects reached to grasp a joystick which was

404 P.J. Bate & E.R. Hoffman relatively fixed, and Marteniuk et al.'s (1987) failure with a fixed disk. However it is not fully convincing because the tasks studied by Jeannerod (1981), Zaal and Bootsma (1993), and Paulignan, Jeannerod et al. (1991) all included lifting objects, and failed to demonstrate an effect of object size on movement time. It is clear that the effect of depth identified in the present experiment can be interpreted as consistent with the results of Marteniuk et a1.(1990). No adequate explanation for the disparity with the results of Wallace and Weeks (1988) and Paulignan (1991) has been identified. 6. CONCLUSION The experiments have supported two quite distinct regimes of control in prehension. It is proposed that the limiting motion is dependent on the amplitude of the transport and the size of the object to be grasped. At small amplitudes the time for adjusting the finger aperture may be greater than that for moving to the object, and hence determine the total time. At larger transport distances, where aperture adjustment can completely overlap with the reach, the transport time may be the limiting time. + In these tasks, the time for the movement was generally linearly related to the square- root of the amplitude of the transport. For distances greater than 90 mm, the total time was independent of the width of the object to be grasped at the end of the transport, and slightly dependent on the depth of the object in the direction of the movement. It was suggested that the movements were made ballistically because of the low values of Index of Difficulty due to the effect of the finger pad length on the effective target tolerance. ACKNOWLEDGEMENT This work was partially supported by the Movement Rehabilitation Research Group of La Trobe University. REFERENCES Arbib, M.A., (1981). Perceptual structures and distributed motor control. In V.B. Brooks (Ed.), Handbook of Physiology:Secl. The Nervous system: Vol 2. Motor Control (pp. 1449-1480). Bethesda Maryland. American Physiological Society.

Limiting Motions in Prehension 405 Arbib, M.A., Iberall, T., & Lyons, D. (1985). Coordinated control programs for movements of the hand. Experimental Brain Research Supplement, 10, 111-129. Barnes, R.M., 1968. Motion and time study: design and measurement of work. 6th Edition, New York, John Wiley and Sons. Bootsma, R.J., & van Wieringen, P.C.W. (1992). Spatio-temporal organisation of natural prehension. Human Movement Science, 11,205-215. Carnahan, H., Goodale, M.A., & Marteniuk, R.G. (1993). Grasping versus pointing and the differential use of visual feedback. Human Movement Science, 12, 219-234. Cole, K.J., & Abbs, J.H. (1986). Kinematic and electromyographic responses to pertubation of a rapid grasp. Journal of Neurophysiology, 57, 1498-1510. Drury, C.G., & Hoffmann, E.R. (1992). A model for movement time on data-entry keyboards. Ergonomics, 35, 129-147. Fitts, P.M. (1954). The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology, 47, 381-391. Gan, K.C., & Hoffmann, E.R. (1988a). Geometrical conditions for ballistic and visually controlled movements. Ergonomics, 829-839. Gan, K.C., & Hoffmann, E.R. (1988b). Sequential ballistic movement. Ergonomics, 31, 1421-1436. Gentilluci, M., Chieffi, S., Scarpa, M., & CastieUo, U. (1992). Temporal coupling between transport and grasp components during prehension movements: effects of visual perturbation. Behavioural Brain Research, 47, 71-82. Hoff, B., & Arbib, M.A. (1992). A model of the effects of speed, accuracy, and perturbation on visually guided reaching. In R. Caminiti, P.B. Johnson & Y. Bernod (Eds.), Control of Arm Movement in Space. Experimental Brain Research Series Supplement 22, Springer-Verlag, Berlin. Hoff, B., & Arbib, M.A. (1993). Models of trajectory formation and temporal interaction of reach and grasp. Journal ofMotor Behaviour, 25, 3, 175-192. Hoffmann, E.R. (1981). An Ergonomics approach to predetermined motion time systems. Proceedings of the 9th National Conference of the Institute of Industrial Engineers, Singapore, 30-47. Hoffmann, E.R. (1993). Sequential visually-controlled movements. Department of Mechanical and Manufacturing Engineering, University of Melbourne.

406 P.J. Bate & E.R. Hoffman Hoffmann, E.R. (in press). Effective target tolerance in an inverted Fitts task. Ergonomics. Hoffmann, E.R., & Gan, K.C. (1988). Directional ballistic movement with transported mass. Ergonomics, 31, 841-856. Hoffmann, E.R., & Sheikh, I.H. (1991). Finger width corrections in Fitts' law: implications for speed-accuracy research. Journal of Motor Behaviour, 23, 259- 262. Jeannerod, M. (1981). Intersegmental coordination during reaching at natural visual objects. In J. Long and A. Baddeley (Eds.), Attention and Performance. New Jersey: Erlbaum. Jeannerod, M. (1984). The timing of natural prehension movements. Journal of Motor Behavior, 16, 3, 235-254. Jeannerod, M., Paulignan, Y., MacKenzie, C., & Marteniuk, R.M. (1992). Parallel visuomotor processing in human prehension movements. In In R. Caminiti, P.B. Johnson & Y. Bemod (Eds.), Control of Arm Movement in Space. Experimental Brain Research Series Supplement 22. Berlin: Springer-Verlag. Keele, S.W. (1968). Movement control in skilled motor performance. Psychological Bulletin, 70, 387-403. l.angolf, G.D., Chaffm, D.B., & Foulke, J.A. (1976). An investigation of Fitts' Law using a wide range of movement amplitudes. Journal of Motor Behavior, 8, 113-128. MacKenzie, C.L., Marteniuk, R.G., Dugas, C., Liske, D., & Eikmeier, B. (1987). Three-dimensional movement trajectories in Fitts' task: implications for control. The Quarterley Journal of Experimental Psychology, 39A, 629-647. Marteniuk, R.G., MacKenzie, C.L., Jeannerod, M., Athenes, S., & Dugas, C. (1987). Constraints on human arm movement trajectories. Canadian Journal of Psychology, 41,365-378. Marteniuk, R.G., Leavitt, J.L., MacKenzie, C.L., & Athenes, S. (1990). Functional relationships between grasp and transport components in a prehension task. Human Movement Science, 9, 149-176. Paulignan, Y., MacKenzie, C., Marteniuk, R., & Jeannerod, M. (1991). Selective perturbation of visual input during prehension movements: 1. Effects of changing object position. Experimental Brain Research, 83, 502-512.

Limiting Motions in Prehension 407 Paulignan, Y., Jeannerod, M., MacKenzie, C., & Marteniuk, R. (1991). Selective perturbation of visual input during prehension movements: 2. Effects of changing object size. Experimental Brain Research, 87, 407-420. Wallace, S.A., & Weeks, D.L. (1988). Temporal constraints in the control of prehensile movement. Journal of Motor Behavior, 20, 81-105. Wing, A.M., Turton, A., & Fraser, C. (1986). Grasp size and accuracy of approach in reaching. Journal of Motor Behaviour, 18, 245-260. Zaal, F.T.J.M., & Bootsma, R.J. (1993). Accuracy demands in natural prehension. Human Movement Science, 12, 339-345.

Motor Control and Sensory Motor Integration: Issues and Directions 411 D.J. Glencross and J.P. Piek (Editors) 9 1995 Elsevier Science B.V. All rights reserved. Chapter 16 PERSPECTIVES ON MOTOR CONTROL AND SENSORY-MOTOR INTEGRATION Jan P. Piek & Nicholas C. Barrett School of Psychology, Curtin University of Technology Perth, Western Australia This chapter provides an overview of the topics presented in the current volume. Many disciplines such as psychology, electrical and mechanical engineering, human movement studies, physiotherapy, neurology, and kinaesiology have been represented, providing a wide range of approaches to our understanding of sensory-motor integration. A major theme of this voume is the integration of these approaches within the framework of the debate between prescriptive and dynamic control. The present chapter suggests a possible compromise between these approaches. 1. INTRODUCTION The introductory chapter by Glencross sets the scene for this volume with the comment \"perception-action-perception\" coupling is the \"very feature which characterizes all hmnan skills.\" (p. 3). Perception and action are seen as being tightly interwoven, such that one cannot be studied in isolation of the other. This tight coupling is a basic tenet of the dynamical systems approach. Glencross argued that treating such an approach as the only correct approach is 'untenable' and 'undesirable'. Self-organizing principles learnt from the dynamic systems approach can explain how we can avoid computations at the central level by offloading many of the details of trajectory planning. Glencross favoured an integration of approaches whereby higher levels make use of self-organizing system dynamics. He argued that self-organizing system dynamics do not preclude higher level control. Indeed this is a view that is encountered in many of the chapters that followed.

412 J.P. Piek & N. C. Barrett 2. NEURAL CONTROL & DISABILITIES OF SENSORY-MOTOR INTEGRATION In Chapter 2, Arbib, Schweighofer and Thach employed the data from both the correction of saccadic eye movements during target perturbation, and the use of prisms in a dart throwing task, to model the adaptive functions of the cerebellum. Studies on macaques with cerebellar lesion (Baizer & Glickstein, 1974) and patients with cerebellar disease (Weiner, Hallet & Funkenstein, 1983) have implied that the cerebellum is important in the process of adaptation. In this chapter, the combination a model based on neuroanatomy and engineering is proposed to account for the complex adaptive functions of the cerebellum. Arbib et al. argued that the cembeUum is responsible for the adjustment of Motor Pattern Generators (MPG's) which are located elsewhere, not in the cerebellum itself. \"Microzones\" are the units for correction of the MPG's that integrate cerebellar and nuclei fibres. Both the correction of saccadic eye movements and prism adaptation to throwing were similarly modeled. The function of the basal ganglia was examined by Iansek, Bradshaw, Phillips, Cunnington and Morris in Chapter 3. They presented evidence from the areas of neuroanatomy, neurophysiology and psychometric studies to examine the control deficits underlying Parkinson's disease. Iansek et al. argued in support of an interactive model concerned with the neural connections between the basal ganglia and supplementary motor areas (SMA) in the execution of well learned, predictable motor sequences. Single cell studies (e.g., Tanji & Kurata, 1985) have indicated that the SMA is involved in the anticipation of an upcoming movement, whereas the basal ganglia provide the internal cue for the next submovement of a movement sequence. The basal ganglia were also associated with the cortical motor preparedness of the complete movement sequence (Brotchie, Iansek & Home, a,b,e). The hypokinesia and akinesia associated with Parkinson's disease appear to be the result of defective control of the internal motor cue and preparatory activity in the basal ganglia. In Chapter 4, Morris, Iansek, Summers and Matyas discussed how the theoretical concepts developed by Iansek et al. and others could be applied to the therapeutic intervention of walking in Parkinson's disease patients. Both cognitive aspects, such as precueing and conscious attentional strategies, and dynamical features of gait, such as the modeling of rhythmical stepping to coupled oscillatory systems, were presented in the development of a suitable rehabilitation programme. This paper provided an

Perspectives on Motor Control and Sensory-Motor Integration 413 innovative link between theory and practice. It demonstrated the ability to explore and integrate several theoretical approaches in order to fully understand mechanisms underlying motor disorders. 3. COMPUTATIONAL & DYNAMIC MODELS OF MOTOR COORDINATION The motor-action controversy is far from resolved and, as other authors have noted (e.g., Beek and van Wieringen, 1994), the issues will 'haunt' researchers for many years yet. The debate provides a fertile backdrop against which researchers from each school may evaluate their ideas. Glencross viewed the result of an extended debate as a trend towards an integrated model, though deep philosophical differences are likely to render such a task problematic. The chapters in this section are supportive of Glencross' view that to stress one approach as a correct approach is 'untenable'. Rather than viewing the debate in terms of deep and irreconcilable differences, Glencross essentially viewed the debate in terms of different levels of description. Neilson, Neilson and O'Dwyer discuss a computational model of the CNS as an adaptive optimal controller of muscles, biomechanics and the external system. They imply that the debate is essentially one of levels and that researchers must ultimately address the internal structures and processes of the system. They argue that computational models that simulate observed motor output and that are consistent with neurophysiology provide at least one solution against which to evaluate neurobiological processes. A problem for such models is to address inherent feedback delays. Neilson et al. provide evidence within the context of a tracking task that the CNS is able to do this by predicting future positions of the target. The issue of computational or cognitive versus dynamical systems approaches was addressed directly in Chapter 6 by Pressing and in Chapter 7 by Abernethy, Burgess- Limerick, Engstrom, Hanna and Neal. Both Abernethy et al. and Pressing hold out for some reconcilliation of approaches. Pressing directly compared cognitive and dynamic approaches within the context of polyrhyOunic tapping using an experimental protocol favouring dynamic control. He used a number of cognitive and dynamical stability indicators as predictors of criterion stability. Both cognitive and dynamical predictors were highly correlated with criterion stability. Furthemore, the differences between cognitive and dynamical predictors was

414 J.P. Piek & N.C. Barrett not statistically significant. Likewise, there was little difference between cognitive and dynamical indicators of interstate transitions. It remains to extend this analysis to tasks favouring cognitive control. In Chapter 7, Abernethy et al. looked at cognitive and dynamical perspectives within the context of human locomotion, to examine invariance of relative timing and the determinants of pattern transitions. The control which humans are able to exert over transition points between walking and running and their ability to sustain non- preferred modes of co-ordination may provide some insights into how an integrated model, such as that proposed by Glencross in the introductory chapter, might be achieved. Abemethy et al. propose a multilevelled gait control system in which higher level cognitive processes may override dynamical systems. 4. ACQUISITION & DYNAMICS OF INTER-LIMB COORDINATION The introduction of the dynamical systems approach in the 1970's led to the development of many new and innovative experimental paradigms to investigate the control of motor coordination. Indeed, the resurgence of interest in motor development over the last decade has been attributed directly to the introduction of this new approach (Savelsbergh, 1993). As in other areas of motor control, there has been a shift over rexT~ntyears from a maturational or cognitive approach to a dynamical systems approach in the investigation of motor development. Piek reviewed both qualitative and quantitative studies that have investigated spontaneous movements in infants. She presented preliminary data from a longitudinal project that is employing time series analysis to determine intralimb and interlimb coordination in order to follow the development of these types of movements from birth to one year of age. Piek suggested that the developmental profiles emerging may be explained more readily from a maturational or cognitive perspective rather than a dynamic systems approach. Inter-limb coordination has received increasing attention over recent years (e.g., Swinnen, Heuer, Massion & Casaer, 1994), and three different approaches that investigated the dynamics of inter-limb coordination were described in Section 4. Summers, Semjen, Carson and Thomas employed a task where the hands produce circles either in symmetrical or asymmetrical mode, in order to determine the control

Perspectives on Motor Control and Sensory-Motor Integration 415 of, and the constraints imposed on, bimanual coordination. Symmetrical circling was found to be the easier task, presumably because the same patterning of muscle groups was used during symmetrical circling. Manual asymmetries were found during the circling which were exaggerated as the frequency of movement increased when the hands moved in the same direction. In addition, when subjects were required to perform asymmetrical circling as fast as possible, trajectory distortions and movement reversals occurred for the nondominant hand which also lagged behind the dominant hand. Summers et al describe the findings both in terms of the system dynamics and also the neural mechanisms that are responsible for the different relationships found between the hands for symmetrical and asymmetrical tasks. This follows on from Summers (1992) thesis suggesting a possible reconciliation between the cognitive and dynamic perspectives. Manual asymmetries were also found by Carson, Goodman, Elliott and Kelso in their first experiment presented in Chapter 10. They examined the kinematics of wrist (flexion/extension) and ankle (plantaro- and dorsi-flexion) movements both in antiphase and in-phase. For single joint conditions, the dominant (right) side demonstrated greater consistency in movement frequency and lower coefficients of variation than the non-dominant hand. When the joints were coupled, the fight side produced a greater uniformity of relative phase, a difference that was more clearly recognised in the anti-phase than the in-phase condition. In a second experiment, Carson et al. were interested in determining whether there was a restructuring of the movement patterning as a result of external pacing, as implied by past neurophysiological evidence (Kelso et al., 1992). The asymmetries detected for the self-paced tasks were eliminated as a result of external pacing. It was proposed that external pacing may result in more widely distributed phasic activity over the cortex providing \"a basis for more precise sequential recruitment of muscles, and ultimately limb segments\". (p. 292). An intentional dynamic appeared to superimpose upon the intrinsic dynamics. In Chapter 11, O'Dwyer & Neilson examined the degree of interlimb coupling during dynamic as well as non-dynamic tracking tasks involving the manipulation of joysticks for the left and fight hands. A scalar relationship was produced between the two hands for the non-dynamic synergy. For the dynamic task, subjects were required to move the fight and left hands at different amplitudes and out of phase with each

416 J.P. Piek & N.C. Barrett other. This was achieved by linearly filtering the input to the right joystick. In both conditions, the subjects produced strong interlimb synergies, with little independent activity between the limbs. Subjects performing the dynamic task did not produce complete f'dter compensation. It was proposed that this was a result of an \"optimal control strategy\" in which there is a compromise between the energy demands of the task and the tracking accuracy. The optimal control strategy is based on the Adaptive Model Theory, a computational model presented by Neilson et al. in Chapter 5 (see also Neilson, Neilson & O'Dwyer, 1992). An important quality of the papers presented in this section is the diversity of approaches taken, including dynamical, cognitive, computational, neural, and an integration of these approaches in several cases. 5. KINAESTHETIC & VISUO-MOTOR COORDINATION Bate and Hoffman examined those factors limiting the movement time of reaching and grasping movements. They delineate two distinct 'regimes' of control in prehension. For small movement amplitudes, the movement time was determined largely by the time required to open the fingers. The movement time of large amplitude movements was determined mainly by the square root of the amplitude of movement. In the chapters by Kerr and Marshall, and Barrett and Kane, the ability of the motor system to adjust for artificially induced movement errors is examined. In Chapter 12, Kerr and Marshall examined how the motor system responds to artificially induced changes in the inertial characteristics of the limb. They evaluated whether the central representation of sensory and motor information might be in intrinsic or extrinsic coordinates. These authors argue that the planning and control of movements can not be accounted for by a purely intrinsic or extrinsic coordinate system. The challenge for Kerr and Marshall is to integrate positional and joint torque control within the one model Barrett and Kane discuss the ability to amend the amplitude of a movement in response to an artificially induced position error. Their interest is in specifying those factors influencing a transition phase across which trajectory modifications are typically observed. The transition phase is consistent with a continuous updating of visuo- spatial error information. Though the amplitude of the initial trajectory is modified

Perspectives on Motor Control and Sensory-Motor Integration 417 rapidly, there are nevertheless delays in the system when generating the corrective response. Performance is determined by the the ability of the system to rapidly update visuo-spatial information, on the one hand, and the inherent limitations in the ability of the system, on the other hand, to plan more than one response at the same time. Wann and Rushton in Chapter 13 address those methodological restrictions which have traditionally meant that naturalistic behaviours have been difficult to study experimentaUy. The benefits of experimental control have largely been traded off against a focus on the analysis of movements which are constrained to one or two dimensions. Though attempts have been made to manipulate the natural environment through prisms, the size of targets and the like the experimenter has been limited in the amount of environmental control that is possible. To study behaviour fully Wann and Rushton argue that we need more 'control over the environmental niche in which we act out the majority of our behaviour' (p. 342). They view the development of increasingly powerful computers and virtual reality as an important era in motor control research. Wann and Rushton illustrate the utility of virtual environment technology in the analysis of 'perception-action-perception' coupling. 6. CONCLUSION Glencross, in the opening chapter, argued that to try to describe motor control through one approach was \"an untenable and indeed undesirable theoretical stance\" (p. 5). His notion of an integrated model provided a background against which to discuss the chapters presented in this volume. These chapters have taken a multi-theory approach by attempting to integrate the more recent dynamic systems approach with the more traditional prescriptive and neurophysiological perspectives. This has lead to some novel approaches in the study of motor control, and provided an avenue for multidisciplinary research. They further offer insights into how the link between the approaches might be forged. A final comment that should once again be noted is the many disciplines that have developed an interest in motor control, and in this particular volume, sensory-motor integration. It is through this multidisciplinary approach that we will be able to fully understand the tight coupling of perception and action.

418 J.P. Piek & N.C. Barrett REFERENCES Baizer, J.S., & Glickstein, M. (1974). Role of the cerebeUum in prism adaptation. Journal of Physiology (London), 236, 34-35. Beek, P.J., & van Wieringen, P.C.W. (1994). Perspectives on the relationship between information and dynamics: An epilogue. Human Movement Science, 13, 519-533. Brotchie, P. Iansek, R., & Home, M.K. (199 la). Motor function of the monkey globus pallidus\" Neuronal discharge and parameters of movement. Brain, 114, 1667-1683. Brotchie, P. Iansek, R., & Home, M.K. (1991b). Motor function of the monkey globus pallidus: Cognitive aspects of movement and phasic neuronal activity. Brain, 114, 1685-1702. Brotchie, P. Iansek, R., & Home, M.K. (1991c).A neuronal network model of discharge patterns on the monkey globus pallidus. Neuroscience Letters, 131, 33- 36. Heuer, H. (1991). Invariant relative timing in motor-program theory. In J. Gagard & P.H. Wolff (Eds.), The development of timing control and temporal organization in coordinated action (pp. 37-68). Amsterdam: North-Holland. Kelso, J.A.S., Bressler, S.L., Buchanan, S., DeGuzman, G.C., Ding, M., Fuchs, A., & Holroyd, T. (1992). A phase transition in human brain and behavior. Physics Letters, A169, 134-144. Neilson, P.D., Neilson, M.D., & O'Dwyer, N.J. (1992). Adaptive model theory: Application to disorders of motor control. In J.J. Summel's (Ed.), Approaches to the study of motor control and learning (pp. 495-548). Amsterdam: Elsevier Science. Savelsbergh, G.J.P. (1993). Perspectives on the development of movement coordination in infancy. In G.J.P. Savelsbergh (Ed.), The Development of Coordination in Infancy (pp. 1-9). Amsterdam: Elsevier Science. Summers, J.J. (1992). Movement behaviour: A field in crisis? In J.J. Summers (Ed.), Approaches to the Study of Motor Control and Learning (pp. 551-562). Amsterdam: Elsevier Science. Swinnen, S., Heuer, H., Massion, J., & Casaer, P. (1994). lnterlimb coordination: Neural dynamical, and cognitive constraints. San Diego: Academic Press.

Perspectives on Motor Controland Sensory-MotorIntegration 419 Tanji, J., & Kurata, K. (1985). Contrasting neuronal activity in supplementary and precentral motor cortex of monkeys. 1. Responses to instructions determining motor responses to forthcoming signals of different modalities. Journal of Neurophysiology, 53, 129-141. Treffner, P., & Turvey, M.T. (1993). Resonance constraints on rhythmic movement. Journal of Experimental Psychology: Human Perception and Performance, 19(6), 1221-1237. Weiner, M.J., Hallet, M., & Funkenstein, H.H. (1983). Adaptation to lateral displacement of vision in patients with lesions of the central nervous system. Neurology, 33.

421 Author Index Abbs, J.H. 384, 403 Atkeson. C.G. 322-325, 328, 329, Abend, W. 323, 336 334, 336 Abernethy,-B. 141, 144, 167, 171-176, 180, 190, 203, 225, 261,282 Augustyn, C. 257, 282 Abrams, R.A. 121,138, 313, 316 Azouvi, P.H. 75, 87 Accomero, N. 323, 336 Baba, D.M. 290, 316 Agarwal, G.C. 105, 121, 135, 137, Bach, T.M. 72, 90, 257, 282 Baev, K.V. 72, 85 174, 191,313, 315 Bagley, S 78, 85 Akert, K. 39, 55 Bai-lin, H. 148, 167 Alafaci, M. 115, 116, 136 Baizer,J.S. 16, 34, 412, 418 Albano, J.E 12, 33 Bak, P. 148, 157, 164, 168 Albus, J. 20, 33 Bakker, H.H. 207, 227 Alexander, G.E 39, 53, 66, 69, 85 Baldissera, F. 232, 247, 249, 258,267, Alexander, G.R. 220, 223 Alexander, R.M. 181, 190 282 Allen, M.C. 220, 223 Ball, J.M. 64, 65, 85 Allen, T. 150, 167 Bampton, S. 174, 191 Anderson, R.A. 28, 34 Banks, M.A. 64, 66, 85 Anderson, S. 179, 191 Banks, M.S. 65, 85, 354, 359 Angel, R.W. 372, 378 Bard, C. 247, 252 Annett, M. 281,282 Barnes, R.M. 388, 394, 405 Aosaki, T. 44, 56 Baron, S. 121,136, 138 Arbib, M.A. 11, 18, 20, 23, 34, 35, 99, Barrett, N.C. 361,363,365, 371,378, 104, 135-137,377,379, 383, 384, 380 388,405 Barrera, M. 220, 223 Armstrong, C.J. 78, 91 Barto, A.G. 22, 25, 26, 33, 36 Arnold, V.I. 148, 167 Basmajian, J.V. 223 Arshavskii, Y.I. 174, 190 Bastion, A.J. 13, 14, 16, 27, 31, 35 Aslin, R.N. 361, 371,377, 378 Bate, P.J. 381 Astrom, K.J. 99, 116, 136 Batschelet, E. 261,282 Athenes, S. 324, 338, 383-386, 388- Bayley, N. 201,223 390, 403, 406 Becker, W. 361, 362, 364, 366-368, 371-373, 377-379

422 Author Index Beech, J.R. 144, 167 Bolam, J.P. 40, 58 Beek, P.J. 143, 146, 156, 165, 168, Bolton, Y. 257, 267, 284 Bonifati, V. 65, 66, 88 256, 286, 290, 317, 335, 339, 413, Bonnard, M 79, 86 418 Bootsma, R.J. 335, 339, 346, 347, Beinrinckx, M.B. 232, 246, 252, 290, 312,317 356, 359, 383-386, 389, 390, 393, Bekoff, A. 218, 223 405, 407 Bendat, J.S. 291, 315 Bowen, K.F. 324, 339 Benecke, R. 47, 54, 70, 85 Box,G.E.P. 113, 136 Berger, W. 80, 87 Bradford, C.M. 345, 346, 355, 358 Bernardi, G. 47, 54 Bradshaw, G. 207, 210, 229 Bernheimer, H. 82, 86 Bradshaw, J.A. 48, 50-52, 55, 56 Bemstein, N 199,201,202, 221,223, Bradshaw, J.L. 37, 38, 48-52, 55-57, 228, 322, 336 66, 67, 69, 70, 84, 86, 88, 91,257, Bertelson, P. 363, 379 282 Bettinardi, V. 357 Brady, J.M. 324, 336 Beuter, A. 189,190 Brazis, P.W. 62, 89 Beverley, K.I. 349, 359 Bressler, S.L. 268,285, 415, 418 BiUer, J. 62, 89 Brinkman, J. 246, 249 Bilowit, D.S. 64, 86 Brooks, D.J. 62, 86 Bingham, G.P. 255, 282 Brotchie, P. 45, 46, 50, 52, 54, 66, 68, Birab, A. 75, 87 69, 78, 79, 87, 412, 418 Birkmayer,W. 62, 86 Brown, R.G. 78, 84, 87, 91 Bistevins, R. 65,90 Bruner, J.S. 205,221,222, 223, 229 Bitmead, R.R. 99, 128, 136 Bruno, N.E. 341,360 Bizzi, E 323, 336, 337 Buchanan, J.J. 232, 250 Blackwell, A.W. 351,352, 353, 360 Buchanan, S. 268, 285, 415,418 Blanco,C. 206, 230 Bullock, D. 142, 167 Blin, O. 62, 64, 86 Bunz, H 172, 191,232, 250, 256, 284 Bock, O. 328-331,336 Burgess-Limerick, R. 171, 174, 176, Boehm, J.J. 208, 226 190, 261,282 Bohr, T. 148, 149, 157, 164, 167 Bumod, Y. 24, 26, 28, 34

Author Index 423 Burrill, C.A. 312, 316 Changeux, J.P. 204, 222, 223 Burton, K. 63, 87 Chapman, A.E. 256, 282, 283 Buryon, H. 40, 56 Chapple, W. 323, 336 Bussel, B. 75, 87 Chevalier, G. 44, 54 Byblow, W.D. 232, 233, 245, 249, Cheyne, D. 51, 56, 248, 251,282, 285 Chieffi,S. 383,405 257, 261, 281-283, 286 Chiu, E. 38, 57, 69, 84, 91 Byme, P.J. 220, 227 Chollet, F. 48, 57 Caird, F.J. 64, 65, 66, 85 Chua, R. 281,282 Calabresi, P. 47, 54 Church, R.M. 146, 170 Calne, D.B. 63, 87 Cioni, G. 206, 212, 224 Calvert, T.W. 257, 282 Civaschi, P. 258, 267, 282 Calvin, W.H. 256, 283 Clark, J.E 73, 74, 87, 92, 173, Caminiti, R. 24, 26, 28, 34 Capaday, C. 323,339 190, 218, 230 Cappozzo, A. 71, 87 Clarke, D.W. 99, 117, 128, 136 Carello, C. 172, 185, 195 Cohen, D.A.D. 26, 34 Carlton, L.G. 315, 316 Cohen, L. 246, 250 Carman, R.C. 207, 210, 212, 217, 227 Cole, K.J. 384, 405 Carnahan, H. 383, 403 Colebatch, J.G. 42, 51, 54 Caron, M.G. 47, 55 Colley, A.M. 144, 167 Carpenter, M.B. 38, 40, 41, 54, 56 Collins, J.J. 73, 87, 181,190 Carson, R.G. 231-233, 241,242, 245, Conde, H. 39, 40, 54 Cooke, J.D. 323, 336 248, 249, 253, 256-258, 261,281- Corbetta, D. 211, 217, 224, 229 283, 286, Corcos, D.M. 105, 121, 135, 137, Carter, M.C. 178, 190 Casaer, P 217 228, 231,252, 414, 418 173, 174, 191, 192, 313, 315 Castiello, U. 383, 405 Corkum, V.L. 199,226 Cattaert, D. 234, 238, 243, 247, 251 Coulter,J.D 40, 56 Cavallari, P. 232, 247, 249, 258, 267, Craik, K.J.W. 98, 103, 136, 201,244 282 Crammond, D.J. 26, 34 Celsis, P. 48, 57 Cratty, B.J. 200, 224 Chaff'm, D.B. 385, 406 Cross, E. 63, 79, 82, 83, 91

424 Author Index Crossman, E.R.F.W. 4, 7 Deniau, J.M. 44, 54 Crowell, J.A.. 354, 359 Denier van der Gon, J.J. 342, 357, Crutcher, M.D. 39, 45, 53, 55, 66, 69, 361,363, 368-371,374, 375, 379- 85 381 Cruz-Neira, C. 343,357 Dennis, C. 67, 86 Cunningham, C. 220, 223 Deubel, H. 361,374, 379 Cunnington, R. 37, 50, 51, 52, 54, DeYoe, R.A. 33, 35, Dick, J.P.R. 47, 48, 54, 70, 85 70,87 Dickenson, G.L 65, 90 Cutting, J.E. 185, 190, 341,350, 357, Diestal,.J.D. 173-175, 194 Dietz, V. 80, 87 358 Ding, M. 268, 285, 415, 418 Darrah, J. 220, 227 Dinse, H. 105, 139 Davidson, S. 220, 226, Disterhoft, J.F. 33, 35 Davis, J.C. 64, 87 Dominey, P.F. 18, 20, 23, 34, 35 Day, B.L. 47, 48, 54, 70, 85 Doshay, L.J. 64, 87 De Caballos, M. 62, 89 Downs, W.J. 62, 72, 75, 90 de Vries, J.I.P. 205, 224 Drury, C.G. 390, 406 de Winkel, M.E.M. 361,380 du Toit, L.L. 171,195 Decety, J. 357 Duetsch, D. 144, 156, 167 Deecke, L. 51, 56, 248, 251,282, 285 Dugas, C. 324, 338, 384-386, 388- Defanti, T.A. 343, 357 390, 406 DeGangi, G.A. 220, 229 DuLac, S. 334, 338 DeGuzman, G,C. 144, 168, 268, 279, Dulitzky, F. 220, 226 Dunne, J.W. 63, 78, 88 285, 290, 316, 415,428 Durding, B.M. 257, 286 Dehaene, S. 204, 224 Easton, J.K.M. 312, 316 Deiber, M.P. 42, 51, 54 Echallier, J.F. 342, 357, 359 Deitz, V. 80, 87 Edelman, G.M. 204, 205, 222, 228 Delagi, E.F. 260, 283 Edis, R.H. 63, 78, 88 Delcolle, J.D. 233, 250, 279, 285 Eikmeier, B. 384, 406 Delcomyn, F. 171, 191 Eldred, E. 24, 36 DeLong, M.R. 33, 39, 41, 44, 45, 55, 59, 69, 87 DeLucia, P.R 343,357.

Author Index 425 Elkind, J.I. 110, 140 Flanders, M.. 24, 28, 34, 334, 339 Elliott, D. 232, 249, 258, 281, 283, Flash, T. 121, 122, 135, 323, 325, 345, 357 329, 336, 337, 376, 379 Ellis, S. 342, 358 Flaster, E 63, 88 Engel, A.K. 281,283 Fleury,M. 247, 252 Engstrom,C. 171, 190 Flowers, K.A. 48, 49, 55, 58, 68, 84, Enoka, R. 335, 337 Essick, G.K. 28, 34 91 Esterly, S. 334, 338 Fodor, J.A. 142, 167 Fabre, N. 48, 57 Forget, R. 247, 252 Fagard, J. 179, 191 Formisano, R. 65, 66, 88 Fahn, S. 91 Forssberg, H. 72, 78, 88, 201,224 Fargel, J.W. 207, 227 Foulke, J.A. 385, 406 Farley, C.T. 181,191 Frackowiak, R.S.J. 42, 51, 54, 56 Farmer, J.D.143, 167 Frank, J.S 290, 315, 317 Fazio, F. 357 Franklyn, S.E. 62-64, 92 Fel'dman, A.G. 335, 336, 368, 370, Franz, E.A. 232, 250 Fraser, C. 384, 386, 407 375,377-379 Freedman, S 324, 337, 342, 358 Fentress, J.C. 222, 224 Freeman,W.J. 142, 167, 169 Fernandez, W. 42, 56, 62, 89 Friston, K.J 42, 51, 54 Ferraina, S 26, 28, 34 Fruend, H.J. 51, 55, 105, 107, 137, Ferrandez, A.M. 62, 64, 86 Ferrari, F. 206, 224 138 Ferrell,W.R. 103, 110, 121,140 Fuchs, A. 268, 285, 415, 418 Finley, F.R. 174, 191 Funkenstein, H.H. 16, 36, 412, 419 Firnau, G. 48, 55 Futami, T. 27, 36 Fisher, C. 22, 25 Galli, C.26, 34 Fisher,D.M. 200, 209-211,229 Gan, K.C. 385, 391,399, 405 Fitts, P.M. 392, 405 Gardiner, T.W. 40, 57 Fitzgibbon, E. 12, 18, 20, 34 Gardiner,C.W. 152, 167 Fitzpatrick, P. 200, 205, 222, 229 Gardner, G.M.. 62, 72,75, 89, 90 Flanagan, J.R. 368, 370, 375, 377, Gamett, E. 48, 55 Gatev, V. 206, 224 379

426 Author Index Gawthrop, P.J. 99, 117, 136 Gopher, D. 98, 140 Gentilluci, M. 381,403 Gordon, G.B. 366, 380, 373 Gentner, D.R. 146, 170, 173-179, 191 Goren,O. 28, 34 Georgiou, N. 48, 50, 51, 55, 66, 88 Gorga, D 220, 225 Georgopoulos, A.P. 25, 26, 34, 45, Goslow, G.E. 174, 190 Gottlieb, G.L. 105, 121, 135, 137, 55, 316, 323, 337, 362, 363, 368, 371,372, 376, 379, 380 174, 191,313, 315,335, 338, 342, Gesell, A. 200, 224 358 Gevers, M. 99, 128, 136 Gottsdanker, R. 363, 379 Ghez, C. 105, 107, 137 Gow, S.M. 131,132, 137 Gibberd, I- B. 65, 88 Gracco, V.L. 173, 191 Gibson, J... 202, 225 Grandguillaume,P. 26, 28, 33 Gielen, C.C.A.M. 362, 363, 370, 372, Gray, C.M. 281,283 374, 375, 379, 381 Green, D.M. 110, 140 Giladi, N. 63, 88 Greer, M. 64, 93 Gingrich, J.A. 47, 55 Gregor, R.J. 174, 175, 193, 194 Glass, L. 144, 167 Gregory, R.L. 134,137 Glatt, S. 62, 75, 89 Gregson, R A.M 151, 167 Glazier, J.A. 165, 167 Griffiths, R. 201,225 Glencross, D.J. 3, 4, 7, 201,203,225, Grillner, S. 71, 72, 88, 174, 191,257, 361,363, 365, 371,378, 380 284 Glickstein, M. 16, 34, 412, 418 Grossberg, S. 142, 167 Gluck, M.A. 28, 34 Guiard, Y. 258, 284 Goldberg, G. 52, 58 Guthrie, B.L. 373, 379 Goldberg, M.E. 12, 18, 20, 34 Haber, S.N 39, 55 Goldie, P.A. 72, 90 Hadders-Algra, M. 209, 210, 213,225 Goodale, M.A. 104, 133, 139, 325, Haken, H. 172, 180, 183, 191, 232, 337, 385, 405 255, 256, 284, 285 Goodkin, H.P. 13, 14, 16, 27, 31, 35 Halbertsma, J. 72, 88, 174, 191, 193 Goodman, D. 232, 233, 245, 249, 257, Hallet, M. 16, 36, 47, 55, 63, 64, 69, 261,281-283, 290, 312, 316 88,412, 419 Goodman, R.F. 178, 194, 200, 225 Halpern, D. 312, 316

Author Index 427 Halsband, U. 51, 55 Heriza, C.B. 220, 225 Halverson, L.E. 173, 193 Herman, R. 174, 191 Hambuch, R. 144, 146, 170 Heuer, H. 72, 92, 176, 179, 180, 217, Hammerston, M. 98, 137 Hammond, G.R. 257, 268, 281, 282, 228, 231,252, 414, 418 Hikosaka, O. 40, 57 284, 287 Hildreth, E.C. 322, 337 Hamstra, S.J. 349, 359 Hinton, G.E. 142, 167 Handel, S. 144, 145, 197 Hirayama, M. 378,379 Hankey,G.J. 63, 78, 88 Ho, K.T. 111 Hanna, A. 171, 190 Hoenkamp, E. 185, 192 Hannon,D.J. 354, 360 Hoff, B. 104, 133, 136, 137, 377, 379, Hari, M. 281,284 Harris, K.S. 173, 195 405 Harrison, D.W. 257, 284 Hoffman, E.R. 383, 385, 390, 393, Hartmann-von Monakow, K. 39, 55 Hasan, Z. 121,137, 313, 315,323, 395, 399, 405, 406 Hogan, N. 121, 122, 137, 313, 315, 335,337 Hassanein, R. 62, 75, 89 323,337 Hassart,T. 206, 229 Hollerbach, J. M. 322-329, 334, 336, Hatsopoulos, N.G. 351,352, 360 Hatze, H. 315 337 Hauk, W.W. 179, 191 Holroyd, T. 144, 168, 268, 279, 285, Hauske, G. 361,374, 379 Hawkins, B. 290, 312, 315, 317 415,418 Hawksworth, J. 65, 88 Holt, K.G. 233, 250 Haykin, S. 106,137 Homberg, V. 64, 88 Hazrati, L.N. 39, 40, 55, 57, 66, 90 Hoover, J.E. 41, 56 Heglund, N.C. 181, 191,257, 284 Hopkins, B. 209, 229 Held, J.P. 75, 87 Horak, M. 142, 168 Held, R. 324, 337, 342, 358 Home, M.K. 45, 46, 50-54, 66-69, 78, Helms, 24, 28, 34 Henis, E. 376, 379 79, 87, 412, 418 Hornykiewicz,K. 62, 86 Horstmann, G.A. 80, 87 Houk, J.C. 22, 32, 34 Hoyt, D.f. 181, 191 Hreljac, A. 181, 192

428 Author Index Hu, Y. 44, 56 Jeka, J.J. 172, 180, 192, 232, 249 Hubbard, M. 343, 358 Jellinger, K. 62, 86 Hudson, P.T.W. 281,282 Jenkins, G.M. 113, 136 Hurrell, J. 49, 58 Jenkins, I.H. 42, 56 Hurwitz, A. 64, 88 Jenner, P. 62, 87 Hyde, M.L. 26, 34 Jensen, J.L. 211,228 Iansek, R. 37, 38, 45, 46, 48-57, 61, Jensen, M.H. 148, 157, 164, 168, 169, 66, 68-75, 77-84, 89, 412, 418 229 Iazzetti, J. 260, 283 Jiang, W.Y. 172, 194 Ibbotson, N.R. 233, 250 Jinnai, K. 39, 59 Iberall,T. 388, 405 Johnels, B. 78, 88 Ibrahim. S. 357, 360 Johnson, B.P. 26, 28, 34 Ikeda, A. 56 Jones, E.G. 40, 56 Ikeda, Y. 12, 25, 35 Jones,D.L 48, 56 Ilson, J. 48, 58 Jones, M.R. 144, 146, 168 Imms, F.J. 62, 63, 92 Jordan, M. 6, 7, 378, 379 Inase, M. 43, 51, 57 Judge, S.J. 345,346, 355, 358, Inman, V.T. 71, 88 Jurgens, R. 361, 366-368, 371, 373, Insulander, A. 65, 91 Isermann, R. 117, 137 375, 378, 379 Ishida, A. 44, 56 Kaiser, M.K. 343, 358, 362, 378 Ito, M. 12, 17, 18, 34 Kakei, S. 27, 36 Ivaldi, F.A.M. 325, 338 Kalaska, J.F. 26, 34, 323, 337, 366, Ivry, R. 173, 192, 257, 258, 284 Jagacinski,R.J. 98, 138, 144, 168 368, 371,372, 376, 379 Jahanshahi, M. 84, 91 Kalish, M.L. 350- 354, 360 Jakobson, L.S. 325, 337 Kamm, K. 211, 229 Jardin, K. 244, 250 Kane, R.T. 361 Jayaraman, A. 40, 41, 56 Katz, K. 220, 226 Jeannerod, M. 104, 133, 139, 324, Kawato, M. 142, 146, 168, 323, 329, 338, 342, 357, 359, 383-386, 388- 339, 377, 378, 380 390, 398, 404, 406, 407 Kay, B.A. 74, 89, 257, 284 Keating, J.G. 13, 14, 16, 27, 31, 35 Keele, S.W. 173, 192, 257, 258, 284, 390, 404

Author Index 429 Kelley, C.R. 99, 138 Komilis, E. 342, 357, 359 Kelly, B. 78, 85 Konig, P. 281,283 Kelly, J.A. 110, 140 Komblum, S. 121, 138, 313, 315 Kelso, J.A.S. 5, 7, 74, 89, 142, 144, Komhuber, A. 51, 56 Komhuber, H.H. 51, 56 172, 173, 180, 191, 192, 194, Kosanovich, N.N. 64, 92 196,232,233, 248,250, 251,255, Koshbin, S. 47, 55, 69, 88 256, 257, 258,268, 278, 279, 281, Koska, C. 248,251 284, 290, 312, 315,316, 372, 380, Kots,Y.M. 174, 190 415,418 Kottke, F.J. 312, 316 Kemp, J.M. 40, 56 Kozlowski, L.T. 185, 191 Kennedy, T. 144, 169, 232, 252 Kravitz, H. 208, 226 Kerr, G.K. 321, 326, 337, 363, 365, Kreiter, A.K. 281,283 367, 372, 380 Krendel, E.S. 99, 108, 109, 110, 138, Ketmer, R.E. 25, 26, 34 Kiemal, T. 172, 192 291,295, 316 Kim, N.G. 172, 195 Kristeva, R. 248, 251,282, 285 Kim, R. 40,41,56 Kristofferson, A.B. 144, 146, 170, Kim, S. 315, 316 Kimura, M. 40, 41, 44, 56, 59, 66, 92 268, 287 King, W.M. 12, 24 Krone, G. 105, 139 Kingma, H. 206, 229 Kugler, P.N 5, 7, 73, 74, 89, 172, 181, Kinnear, E. 65, 88 Klapp, S.T. 144, 146, 168,290, 316 184, 193, 195, 233, 250, 256, 257, Kleinman, D.L. 121, 136, 138 285, 287, 322, 338 Klip-Van den Nieuwendijk A.W.J 209, Kunzle, H. 39, 55 210, 213, 225 Kurata, K. 43, 44, 58, 66, 68, 92, 412, Klopf, H. 22, 33, 34, 35 419 Knott, M. 64, 65, 89 Kurtz, K.J. 351-353, 360 Knudsen, E.I., 334, 338 Kuypers, H.G.J.M. 246, 249 Knutsson, E. 62, 71, 75, 80, 89 Kyprie, P.M. 257, 287 Kojima, J. 40,57 Lachmann,K. 117, 137 KoUer, W.C. 62, 75, 89 Lacquaniti, F. 322, 324, 328, 334, 338, 339, 363, 380 Laissard, G. 179, 195

430 Author Index Lalonde, F. 189, 190 Lui, B.K. 130, 138 Lamarre, Y. 247,252 Lukeman, D. 221,226 Lander, C.M. 63, 92 Lyons, D 386, 403 Lang, A. 84, 91 Lyshkow, H. 42, 58 Lang, M.,,51, 56 Mace, W. 334, 339 Lang, W. 56, 51,248, 251,282, 285 MacKenzie, C.L. 233, 251,290, 316, Langolf, G.D. 385, 406 Largo, R.H. 219, 226 .324, 338, 383-390, 398, 403, 404, Larsen, B. 41, 42, 52, 58 406 Larsen, T.A. 63, 68, 87, 91 Lashley, K.S. 4, 5, 7, 222, 226 Mackey, M.C. 144, 167 Lassen, N.A. 41, 42, 52, 48, 68, 91 Macmillan, D.L. 174, 190 Latash, L.P. 211,226 MagiU, R.A. 173, 193 Latash, M.L. 211,226, 335, 338 Mallot, H.A. 105, 139 Laurent, M 83, 89, 357, 358 Mandir, A.S. 50, 59 Leavitt, J.L. 383, 384, 386,403, 406 Manetto, C. 44, 56 Lee, D.N 78, 89, 92, 354, 360 Manning, J. 257, 267, 284 Lees, A.J. 42, 56, 63, 92 Mardia, K.V., 261,265, 275, 285 Levinson, W.H. 121,136, 138 Marini, G. 232, 249 Lewis, F.L. 123, 138 Marsden, C.D 47, 48, 54, 62, 64, 69- Libchaber, A. 165, 167 Licklider, J.C.R., 99, 138 72, 78, 84, 85, 89, 90 Lidsky, T.I. 44, 56 Marshall, R.N. 321,326, 337 Liemohn, W.P. 268, 287 Marshblum, E. 144, 146, 168 Lindberger, G. 51, 56, 248, 251,282, Marteniuk, R.G. 290, 316, 324, 338, 285 383-390, 398, 403-406 Lishman, J.R. 78, 89 Martensson, A. 62, 89 Liske, D 382, 404 Martin, J.P. 62, 77, 79, 81, 83, 89 Llewellyn, K.R. 350, 352, 358 Martin, K.E. 49, 51, 56 Lodgsdon, J.B. 121,135, 313, 315 Martin, T. 13, 14, 27, 31, 35 Love, G.L. 365, 380 Massey, J.T. 323, 337, 362, 365, 366, Luders, H.O. 56 369, 372, 375, 378, 379, 380 Massion, J. 72, 92, 217, 228, 231, 252, 414, 418 Mathias, C. L 62, 86

Author Index 431 Matko,D. 117, 137 Mitchell, S. 39, 55 Matsumura, M. 40, 57 Modarelli, F.T 65, 66, 88 Mattingley, J.B. 48, 50, 51, 55, 66, 67, Mohtadi, C. 99, 117, 128, 136 Montastruc, J.L 48, 58 86, 88 Mon-Williams, M. 355, 358 Matyas, T 61, 72, 77-80, 83, 89, Moore, S.P. 324, 337 Mayeux, R. 48, 58 Morasso, P. 322, 323, 325, 337, 337 Mazziotta, J.C. 357 Moray, N. 98, 99, 138 McCabe, G. 232, 250 Morris, M.E. 37, 61, 72, 75, 77-80, McClelland, J.L. 28, 35 McDonnell., P.M. 199, 336 82,83, 89, 90 McGoon, D.C. 63, 77, 79, 82, 83, 89 Morris, M.W 350, 351,353, 354, 360 Mcleod, R.W. 343, 358 Morris, R. 366, 380 McMahon, D. 63, 88 Morrison, D. 260,283 McMahon, T.A. 177, 193, 257, 284 Mortimer, J.A. 65, 90 McRuer, D.T. 99, 108-110, 138, 291, Morton, J. 233, 250 Mowafy, L. 343, 358 295, 316 Moyer, J.R.Jr. 33, 35 Meco, G. 65, 66, 88 Mugnaini, E. 18,35 Melvin, D. 221,226, Murphy, G.N. 171, 195 Mercuri, N.B. 47, 54 Murphy, M.G. 16, 35 Merlob, P. 220, 226 Murray, P. 62, 72, 75, 90 Merton, P.A. 173, 193 Mushiake, H. 43, 51, 57, 58 Meugens, P.F. 232, 252, 290, 312, Musil, S.Y. 12, 18, 20, 34 Mussa-Ivaldi, F.A. 26, 35, 335, 338 316,317 Myers, C. 28, 34, 272, 285 Meulenbroek, R. 244, 250 Nahmias, C. 48, 55 Meyer, D.E. 121, 138, 313,315, 316 Nakano, K. 40, 56 Meyer, E. 41, 42, 58, 66, 91 Nakayama, K. 351,358 Miles, D. 75, 92 Nambu, A. 39, 59 Miles, F.A. 355, 358 Naor, N. 220, 226 Milgram, P. 345, 357 Nashner, L. 71, 90 Miller, J.F. 178, 193 Navas, F. 103, 138 Mink, J.W. 44, 45, 57 Minnigh, S.C. 64, 89

432 Author Index Neal, R.J. 171, 174, 176, 190, 261, Orgogozo, J.M. 52, 57 282 Orlovskii, G.N. 71, 91, 174, 190 Ostry, D.J. 368, 369, 370, 375, 377, Neilson, M.D. 101, 103, 105, 106, 112, 115, 126, 129, 139, 298, 313, 316, 379 416,418 Otto, I. 26, 28, 34 Ozel, A.T. 312, 316 Neilson, P.D. 97, 101, 103, 105, 106, Page, N.G.R. 65, 88 113, 115, 126, 129, 291,298, 313, Pailhouse, J.. 62, 79, 83, 86, 89 317,416,418 Paillard, J. 247, 252 Palmans,L 206, 229 Nelson, W.L. 121, 122, 323,338 Palmer, S.S 65, 90 Nettleton, N.C. 257, 282 Parent, A. 39, 40, 55, 57, 58, 66, 90 NeweU, K.M. 65, 90, 221,230, 315, Parker, H. 200, 221,226 Parkes, J.D. 63, 89 316 Parkinson, J. 63, 84, 90 Nilsson, J. 79, 90, 174, 190, 193 Partridge, L.D. 291, 316 Nise, N.S. 109, 139 Pashler, H. 103, 139 Nixon, P.D. 42, 51, 54 Passingham, R.E 42, 51, 54, 56 Noda, H. 12, 20, 35, 36 Patla, A.E. 71, 72, 73, 78, 90, 233, Nolte, R. 205, 227 Norman,D.A. 142, 169 251 Nutt, J.G. 71, 72, 90 Paulignan, Y. 384, 386, 398,404, 406, O'Dwyer,N.J 97, 101,103, 407 105,106,112, 115, 126, 129, 139, Pearson, J.C. 140 298, 313, 316, 317, 416, 418 Pearson, K.R. 174, 190 O'Leary, M. 16,35 Pederson, S.W. 65, 91 Oberg, B. 65,91 Pelisson, D. 104, 133, 139 Obeso, J.A. 69, 89 Peper, C.E. 143,146, 156, 165, 168 Oguztoreli, M.N. 323, 339 Perani, D. 357 Ojemann, G.A. 257, 285 Perotto, A. 260, 283 Oldak, R. 343,359 Peter, P. 38, 40, 54, 56 Oldfield, R.C. 258, 285 Peters, M. 144, 168, 232, 233, 234, Olson, C.R. 12, 18, 20, 34 Optican, L 12, 35 245, 251, 257, 281,282, 286, 290, Orbig, H. 282, 285 316

Author Index 433 Pew, R.W. 98, 139 Purves, D. 227 Philippson, M. 173, 193 Pylyshyn, Z.W. 142, 167 Phillips, J.G. 37, 38, 48-57, 66, 67, 69, Quinn J.T. Jr. 290, 312, 315, 317 Quinn, N. 63, 89 70, 84, 86, 88, 91 Quintyn, M. 63, 79, 82, 83, 91 Piek, J.P. 199, 207, 212, 217, 227, Ralston, H.J. 71, 88 Rascol, O 48, 57 365, 380 Regan, D. 349, 359 Piersol, A.G. 291, 315, Reinking, R.M. 174, 190 Pijpers, J.R. 346, 347, 359 Richter, L. 38, 57 Pinhasov, A. 82, 93 Ridley-Johnson, R. 200, 210, 217, 229 Piper, M.C. 220, 227 Riek, S. 257, 286 Plant, Y. 257, 267, 284 Risken, H. 166, 168 Playford, E.D. 42, 56 Ritchie, L. 12, 35 Pokomy, R.A. 173, 192 Roberthson, H. 189, 195 Polit, A. 323, 337 Roberton, M.A. 173, 193 Porter, J.D. 373, 379 Robertson, C. 68, 84, 91 Porter, R. 40,56 Robertson, S.S. 208, 227 Poulton, E.C. 98, 103, 108, 110, 139, Robi-Bramby, A. 75, 87 Robinson, C. 78, 91 140 Robinson, D.A. 12, 35 Powell J.S. 40, 56 Rodionov, I.M. 174, 190 Prablanc, C. 104, 133, 139, 342, 357, Roland, P.E 41, 42, 52, 58, 66, 68, 91 Romo, R. 43, 46, 50, 58 359 Rosen, J. 48, 58 Pratesi, L. 65, 66, 88 Rosenbaum, P. 220, 223 Prechtl, H.F.R. 205-213, 220, 224, Rosenblum, D. 6, 7, 144, 169, 181, 227 195, 256, 257, 282, 285, 287 Pressing, J. 141,144, 165, 168, 232, Rosenthal, R. 159, 196 Rosnow, R. 159, 169 252 Ross, G. 220, 225, 343, 358 Prestidge, S.P. 62, 63, 92 Rossignol, S. 72, 88 Price, H.L. 257, 287 Proffitt, D.R. 185, 191 Provine, R.R. 205, 227 Prud'homme, M. 26, 34 Przedborski, S. 63, 88

434 Author Index Roth, K. 173, 193 Schmidt, R.C 142, 169, 181,195, 155, Rothwell, J.C. 47, 54 282, 285-287, 290, 317 Rouse, W.B 99, 139 Rouselle, C. 257, 286 Schneider, K. 211,228, 229 Roy, E.A. 84, 91 Scholz, J.P. 142, 144, 168, 184, 192, Roydon, C.S. 354, 359 Rubin, P. 233, 250 232, 251,255, 278, 279, 285 Rumelhart, D.E. 28, 35, 142, 169 Schoner, G. 142, 144, 168, 169,172, Runeson, S. 185,194 Rushton, S.K. 341,349, 354, 355, 358 182, 184, 233, 251,255-257, 279, Sabatini, U. 48, 55 285 Sadato, N. 42, 55 Schultz, W. 43, 46, 50, 58 Sadikot, A.F. 40, 58 Schwab, R.S. 47, 58, 70, 92 Saint-Cyr, J. 84, 91 Schwartz, A.B. 25, 26, 34, 372, 375, Salmon, E.P. 62, 86 380 Saltzman, E.L 74, 89, 257, 284, 324, Schwatz, S. 232, 251 Schwieghofer, N. 11, 18, 20, 23, 26, 334, 338 35 Samways, M. 78, 91 Seitz, R.J. 42, 58 Sancesario, G. 47, 54 Selverston, A.I. 71, 72, 91 Sanderson, D.J. 256, 283 Semjen, A. 231,234, 238, 243, 247, Sandin, D.J. 343, 357 251 Sanger, T.D. 26, 35 Senard, J.M. 48, 57 Sarnat, H.B 204, 228 Sepic, S.B 62, 72, 75, 89, 90 Savelsburgh, G.J.P. 203, 205, 228, Serratrice, G. 62, 64, 86 Setelberger, F. 62, 86 346, 347, 349, 359, 414, 418 Severin, F.V. 71, 91 Scarpa, M. 383, 405 Shadmehr, R. 335, 338 Schaffer, L.H 290, 316 Shaffer, L .H. 312, 317 Schell, G.R. 40, 54, 66, 67, 91 Shahar, G. 82, 93 Schiff, W. 343, 359 Shapiro, D.C. 173-175, 178, 190, 194, Schmidt, R.A. 144, 169, 172, 173, 202, 228, 232, 252 Sharp, R.H. 345, 359 194, 201,202, 228, 290, 312, 315- Shaw, G.L. 105, 140 317, 365, 366, 373, 380 Shaw, R.E. 334, 339

Author Index 435 Shea, S.L. 361, 371, 378, 391 Soliveri, P. 84, 91 Sheikh, I.H. 388, 404 Soule, R. 178, 194 Shepard, R.N. 151, 169 Southard, D.L. 290,312, 316 Sheppard, W. 64, 92 Sparks, D.L. 373, 379 Sheridan, M.R. 49, 58 Sparrow, W.A. 141, 144, 167, 313, Sheridan, T.B. 6, 7, 103,110, 212, 317 140 Spencer, K.M. 65, 88 Sherwood, D.E. 290, 317 Spores, O. 204, 205, 222, 228 Shibasaki, T. 41, 42, 58, 66, 91 Sriharan, A. 313, 317 Shik, M.L. 71, 91,174, 190 Sroka, H. 82, 93 Shimansky, Y.P. 72, 85 Stamford, B.A, 178, 193, Shimizu, H. 181, 194 Stark, L. 99, 103, 121,138, 140 Shinoda, Y. 27, 36 Stassen, H.G. 99, 140 Shoenberg, B.S. 91 Steams, S.D. 106, 140 Siegal, R.M 28, 34 Steg, S. 78, 88 Sietz, R.J. 28, 33, 42, 58, 66, 68, 91 Stein, J.F. 334, 339 Silverman, D. J. 105, 140 Stein, R.B. 323, 339 Singer, W. 281,283 Stelmach, G.E., 144, 167, 373, 380 Singh, S.P.. 22, 26 Stem, F.M. 63, 92, 220, 225 Skarda, C.A. 142, 169 Stem, G. M. 62, 92 Skinhoj, E. 52, 58, 68, 91 Stem, Y. 48, 58 Skinhoj, N.A. 41, 42, 58 Stevens, A. 206, 229 Smiley, A.L. 281,287 Stewart, I.N. 73, 87, 181,190 Smiley- Oyen, A.L. 257, 287 Stowell, A. 36 Smith, M.12, 18, 20, 34 Strata, P. 16, 36 Smith, W.M. 324, 339 Strick, P.L. 40, 41, 54, 56, 66, 67, 91 Smith, J.E.K. 121,138, 313, 315, 316 Stuart, D.G. 174, 190 Smith, Y. 40, 58 Stucchi, N. 244, 252 Smithson, F. 75, 82,91 Sugita, S. 12, 35 Snider, R.S. 36 Summers, J.J. 61, 72, 77, 79, 80, 83, Soechting, J.F. 28, 34, 324, 325, 328, 89, 90, 141,144, 165, 167, 169, 334, 339, 363, 380 173,194, 203, 228, 231,232, 234, 238, 234, 247, 251,252, 415, 418

436 Author Index Sutherland, I.E. 355, 359 Tillery, S.I. 24, 28, 34 Sutton, R.S. 22, 33, 35 Todd, J.T. 185, 195 Suzuki, R. 146, 170, 323, 329, 339, Todor, J.I. 257, 281,287 Tokuno, H. 40, 41, 59, 66, 92 376, 377, 380 Touwen B.C.L. 206, 229 Swinnen, S.P. 72, 92, 217, 228, 231, Treffner, P.J. 141,144, 146, 147, 150- 232, 244, 246, 250, 252, 290, 312, 157, 163, 166, 169, 252, 256, 286, 316,317,414,418 419 Szekey, B.C. 92, 64 Tresilian, J.R. 350, 359 Tadary, B. 357 Trevarthen, C. 257, 287 Taga, G. 181,194 Truman, G. 257, 281,287 Talland, G.A 47, 58, 70, 92 Tufts, P.S. 99, 117, 128, 136 Tanji, J. 40, 41, 43, 44, 55, 57, 58, 59, Tuller, B. 173, 193, 195 66, 68, 92, 412, 419 Tuller, M.T. 246, 252 Tassone, G. 232, 249 Tunnicliffe, N 78, 85 Taylor, C.R. 84, 91, 181, 191, 192, Tumbull, G. 78, 85 257, 284 Tumbull, J. 357, 360 Teasdale, N. 247, 252 Turner, A. 281,282 Terzuolo, C.A. 173, 193, 194, 328, Turton, A. 384, 386, 407 338 Turvey, M.T. 73, 74, 78, 89, 92, 141, Tesio, L. 247, 249 142, 144, 146, 147, 150-157, 163, Thach, W.T. 11, 13, 14, 16, 27, 31, 166,169, 172, 181, 183-185, 193, 32, 35, 44, 57 195, 205, 222, 229, 255, 282, 286, Thelen, E. 75, 92, 200, 202, 205-210, 290, 317, 419 217, 228, 231 Tzeng, O.J.L. 257, 287 Thompson, C.J. 66, 91 Ulrich, B.D. 75, 92, 203, 211, 228, Thompson, P.D. 71, 72, 90 229 Thompson, R.F. 28, 34 Ulrich, D.A. 203, 229 Thomson, J. A. 78, 89, 357, 358 Umphred, D.A. 64, 65, 92 Thorstensson, A. 79, 90, 174, 189, Uno, Y. 323, 329, 339, 377 191, 193, 195 Valvano, J. 220, 229 Thuring, J.P. 342, 357 van Asten, W.N.J.C. 45, 361,380 Tillemans, T. 281,284

Author Index 437 van de Waerden,B.L. 159, 169 Vretman, M. 65, 91 van den Heuval, P.J.M. 362, 363, Vu, D.H. 110, 140 Walker, J. 78, 85 372, 378 Wallace, S.A. 232, 250, 385, 386, Van Emmerik, R.E.A. 221,230 Van Eykem, L.A. 209, 210, 213, 225 388-390, 398, 403, 405 Van Hofsten, C. 203, 230, 221 Walter, C.B. 178, 194, 232, 246, 252, Van Hoesen, G.W 40, 59 van Ingen Schenau,G.J. 335, 339 290, 312, 316, 317 van Kampen,N.G. 152, 169 Walters, M.R. 241,242, 253 van Kranen-Mastenbroek, V. 206, Wang, W.S.Y. 257, 287 Warm, J.P. 341, 349, 354, 355, 357, 229, 330 van Oostenbrugge, R. 206, 230 360 van Santvoord, A.A.M. 346, 347,349, Ward, J.A. 207, 210, 229 Warren, R. 343, 357 359 Warren, W.H., Jr. 78, 92, 173, 195, van Sonderen, J.F. 363, 369, 370-372, 350-354, 357, 360 375, 380, 381 Watt, M.J. 220, 222 van Wieringen, P.C.W. 143, 146, 156, Watts, R.L. 50, 59 Webster, D. D. 65, 90 165, 168, 189, 195, 382, 387, 403, Weeks, D.L. 386- 390, 398, 403, 407 413,418 Weiner, M.J. 16, 36, 412, 418 Vaughan, C.L. 171,195 Weinmann,H.M. 207, 227 Veldhuyzen, W. 99, 140 Weinrich, M. 51, 54 Vereijken, B. 141, 144, 167, 221,230 Weissenbom, S. 78, 92 Vetere-Overfield, B. 62, 75, 89 Weissendanger, M. 5, 41, 59 Vince, M.A. 365, 381 Weissendanger, R. 41, 59 Visser, G.H.A 205, 225 Welford, A.T. 103, 140, 365, 381 Viviani, P. 173, 179, 194, 195, 244, Wertz, V. 99, 128, 136 252 Whitall, J. 73, 74, 92, 218, 230 Vies, J. 206, 229 Whiting, H.T.A. 141, 144, 170, 221, Vogt, S. 141, 144, 167 von Hofsten, C. 203, 221,230 230, 345-347, 349, 359, 360 von Seelan, W. 105, 139 Wichmann, T. 38, 41, 59 Vorberg, D. 144, 146, 170 Wickens,C.D. 98, 140

438 Author Index Widrow, B. 106, 140 Zelaznik, H.N. 232, 252, 290, 312, Wielunsky, E. 220, 226 315,317 Wilson, D.L. 71, 93, 199, 226 Wilson, D.M. 37, 59, 71, 93 Zemicke, R.F. 173-175, 194, 211, Wing, A.M.. 144, 146, 170, 268, 287, 228, 229 382, 384, 405 Zilch, O. 248, 251 Winter, D.A. 71, 74, 93, 174, 178, 196 Zuberec, 345, 357 Wirta, R. 174, 191 Wise, S.P. 51, 59 Wittenmark, B. 116, 136 Wolf, W. 361,374, 379 Wolff, P.H. 179, 191,208, 221,230, 257, 286 Woods, R. 357 Wright, C.E. 121,138, 313,315, 316 Wrisberg, C.A. 268, 287 Wroe, M. 64, 93 Yakouleff 75, 87 Yamada, J. 20. 36 Yamaguchi,Y. 181,194 Yamamoto, Y.L. 41, 42, 58, 66, 91 Yamanishi, J. 146, 170 Yang, J.F. 178, 196 Yekutiel, M.P. 82, 93 Yeterian, E.H. 40, 59 Yonekura,Y. 42, 58 Yoshida, S. 39, 59 Young, D.S. 78, 92, 110, 140 Young, L.R. 99, 121,140 Zaal, F.T.J.M. 383, 385, 386, 389, 390, 398, 407 Zanone, P.G. 173, 196

439 Subject Index accommodation 355 task 147 accuracy speed trade-off 107, 121 binocular disparity 343 action systems 141 bradykinesia 38 adaptation 11-32, 108, 321,324, 326 central pattern generators 71-73, 171 cerebellar speed of 110 adaptive ataxia 16, 62 cortex 17, 20, 41 control theory 99 cerebellum 11-13, 16-20, 23-27, 32, optimal control 99, 115, 120, 121, 72, 173, 412 cognitive approach 141-145, 151, 166, 127, 313, 416 181,201,412-414 value 204 coherence 295-300, 304-307, 311 Adaptive Model Theory (AMT) 101- collective variables 203, 232, 233, 256 104, 108, 129,130, 133-135 computational afferent feedback 247 approach 5 affordances 357 models 101, 134, 413 aiming tasks 290, 385, 386 connectionist approach 5, 141, 142 akinesia 38, 62, 64, 69, 82, 412 contextual variation 5, 201 Amplitude Transition Function (ATF) control 361,366 open-loop 48, 100, 390 apoptosis 204 parameters 182, 183, 258 Arnol'd tongues 149, 155-160, 163- systems 165 aspect ratio 241,242 manual 361,364, 365, 373 balance 75, 82 oculomotor 361,364, 366, ballistic movements 69, 105, 111, 112, 370 392, 393, 400 convergence 355 basal ganglia 37-53, 62, 66-70, 72, 78- coordinate space 321 80, 85, 412 coordinate system 322, 324 basic unit of motor production extrinsic 321,322-325, 334, 335, (BUMP) 102-104 416 bimanual intrinsic 322, 325-329, 334, 335, circling 231, 241, 415 416 coordination 233, 234, 244, 281, 289, 292, 293, 305, 415

440 Subject Index coordination nonlinear systems 143 dynamics 278 properties 281,291 interlimb 217, 232, 234, 292, 414 dyskinesia 63,64 interjoint 211,212 dystonia 63 intralimb 211,234, 258, 290, 414 ecological theory 141,202 symmetrical 245, 246 effector system 384 temporal 171, 177 efference copy 100,374 entrainment 74, 279 coordinative structures 202, 268 equilibdum-point hypothesis 335, 375, corollary discharge 21 376 corpus callosum 246 error corrective reaction time 361-367, 371, detection 28 tolerance 388-390, 393 372 tracking 109, 309 coupled oscillators 73, 74, 148, 267, visuo-spatial 361 external 412 cues 48, 70 critical fluctuation 183, 187, 189 load 327-329 cyclic motility 208, 209 pacing 268-282, 292 degrees of freedom 6, 24, 201, 221, extrinsic coordinate system 321,322-325, 222, 255, 256, 314, 323 determinant time interval (D) 361, 334, 335, 416 properties 382 363, 364, 366-368,371,373,375, Farey tree 151,155, 157 378 feedback developmental Schedules 200 afferent 247 double step tracking 361-378 continuous 382 dynamic kinaesthetic 100,246, 247 attractors 203 visual 12, 321 synergy 291,292, 312, 314 feedforward 29 systems 73, 101, 102, 134, 172, fibres 189, 411 climbing 17, 21, 22, 29 dynamical approach 5, 6, 141-145, 166, 173, 180, 181,205, 232, 255,413, 414

Subject Index 441 mossy 17-21, 32 homunculus error 142 parallel 18, 20, 22 Huntington's disease 38 filter hypokinesia 47, 49, 62, 64, 69, 72, 77, compensation 301,302, 304-311, 80, 81-84, 412 313,416 hysteresis 183, 187 digital 99 index of difficulty (ID) 392, 393, 395, low-pass 261,291,294, 300, 303, final amplitude responses (FARs) 367, 404 ,~ 373 infant Fitts' law 121,313, 390 focus of radial outflow 350- 352 cyclic motility 208, 209 foetal motility 205, 206 spontaneous movements 199, gain 21,113-115, 118-120, 295-300, 200, 205-223, 414 307, 311 preterm movement 219, 220 gait 171 inferior olive (IO) 16, 18, 19, 21, 22, akinesia 63 29 control 70, 71, 171 information digitigrade 201 processing 101 disorders 62 processing approach 141, 142, kinematics 174, 175-178 381 plantigrade 201 interlimb asymmetries 245-249, 257, timing 73, 171-190 258, 262, 281 general movements 206 intermediate amplitude responses generalised (IMARs) 367, 374 minimum variance 117 intermittency 103, 106, 130 motor programs 202 interstimulus interval 361,363, 367- prediction controller 117, 118, 371,376 121 intrinsic grasping 383, 385, 400 coordinate system 322, 325-329, gravitational scaling 330 334, 335, 416 hierarchical organization 5 cues 49, 53, 68 hippocampus 32 dynamics 143, 233, 279 properties 381,382 invariant features 172, 173, 179, 202, 414

442 Subject Index inverse dynamics 322, 330, 331 pattern generators (MPGs) 11, joint angle 13, 23, 32, 412 displacement 211 planning 334 kinematics 171 program 201,364, 374-376 velocities 211,323 kinaesthetic feedback 100, 246, 247, generalized 202 321,322, 326 programming 141,142, 172 kinematics 171, 175-178, 261,326, set 68 331,335 movement lambda (Z,)model 335, 375 amplitude 385, 387, 390-392, limb synergies 291 394-404 dynamic 291,292 perturbation 74, 241,323, 325, non-dynamic 291,292 327 linear behaviour 314, 315 rehabilitation 64-66, 80-85 manual control 361,364, 365, 373 sequencing 44, 45, 49 mass-spring 202 synergies 291 master equation 152 time 385-404, 416 maturational approach 200, 206, 414 muscle microcomplex 17, 23 co-activation 209, 210, 213, 246 microzones 17, 18, 29, 32, 412 co-contraction 209, 210, 213, 246 minimum force 73, 74 jerk model 323, 376, 377, 378 rigidity 37, 38, 63 torque change model 377 tremor 37, 38, 63 variance controller 116-120 neural modality 183, 184 modeling 24-29 motion parallax 350 networks 141 motor neurophysiology 5 behaviour modeling 141 non-linearity 203, 315 control 334 non-linear oscillator 73, 148, 232 cortex 39, 40, 42-46 occlusion 342 instability 47 oculomotor 361,364, 366, 371 open-loop control 48, 100, 392 optical looming 343, 346-349

Subject Index 443 order parameters 181, 183, 185, 232, continuous-time 103 256 parallel 5, 101, 102, 141,376 programming 6, 172, 173 Parkinson's disease 39, 47-53, 61-67, proprioceptive 69-72, 75-85, 412 information 321,326 neuromuscular facilitation 64 perception 341 psychological refractory period (PRP) perception-action coupling 3, 185, 363, 364 pulse 411,417 overshoot (PO) 362-367, 372, peripheral-centralist debate 4 378 phase 295, 308 undershoot (PU) 362, 363,364, 367, 371,377 lag 113-115, 118-120, 213-219, Purkinje cell (PC) 17-24, 29-31 235-238, 244-245, 291 reaching 131,383,400 locking 208, 281 reaction time 364, 373 profile 185, 186, 188 corrective 361-367, 370- 372 transitions 74, 181, 183, 184, 189, initial 362, 363, 365 232, 233, 256 relative physical phase (in-phase/anti-phase) 182, systems 181-184 183, 232, 233, 244, 260, 261,263, therapy 64, 65 265-267, 270-282, 290, 415 polyrhythms 144-147, 155, 163, 166, timing 172-190 232, 413 response positron emission tomography (PET) execution 102, 108 42, 68 planning 102, 106 postural control 75 resulting joint moments 329-334 prehension 383-390, 393-404, 416 premotor cortex 26, 27, 39, 68-70 rhythmical premovement activity 43, 44, 51 prescriptive approach 141, 172, 201 kicking 210 preterm infant movement 219, 220 movement 72, 208, 258, 290 primitive reflexes 199, 200 stepping 71, 75, 81 prism adaptation 13-16, 19-32, 324, stereotypies 206 342, 412 processing

444 Subject Index saccade 12, 13, 18,373, 374 symmetrical pulse (SP) 362, 364 generators 20, 21 synergetics 180, 181, 189 synergy 291, 299, 300, 311 Saccadic responses 361,364, 365 dynamic 291,292, 312, 314 suppression 12 non-dynamic 291, 292, 314 synchronisation 232, 290 selectionist approach 204 system dynamics 73, 101, 102, 134, self-organising systems 5, 172, 181, 172, 189 systems theory 143 183, 184, 203, 211,411 tachykinesia 49 self-tuning regulator 117 tangential velocity prof'de 323,328 sensory-motor target perturbation 12, 133, 134 integration 3-5 prediction 113 representation 334 size 385, 386, 388, 390 sequencing 4 width 385, 386 serial Tau 78, 346-349 order 4, 5 temporal processing 5 coordination 171, 177 servomechanisms 201 integration 4, 372 simulation 99, 101, 104-106, 329-331 invariance 171-189, 210, 414 sine circle map 148-150 occlusion 345, 346 somaesthetic information 321,326 proportionality 172, 173, 176, somatic selective processes 204, 205 177-180 spatial scaling 345, 346 sequencing 46 speed-accuracy trade-off 107, 121 thalamic projections 41 spontaneous movements 199,200, time clock 173 205-223, 414 time-to-contact (see Tall) 346-349 staircase stimuli (SC) 362, 363, 364, tracking 98-101, 103, 107-111, 113- 367, 371 121, 129, 130, 293, 295, 299, 303- stance phase 174 315 stereotypic mannerisms 208 double-step 361-378 supplementary motor area 37-53, 67- 70, 78, 80, 412 swing phase 174

Subject Index 445 error 109,309 pursuit 119 single step 365, 372 step 378 visual 99-101, 116 virtual haptic array 356 reality 342 virtual environments 342-357, 417 dual channel system 343, 348, 355 head-mounted display 343-345, 355 single channel system 342, 343, 355 stereoscopic 343, 344, 348, 354 visual cues 48, 78 feedback 12, 321 tracking 99-101, 116 visuo-motor information 363