Alexander GE, Crutcher MD (1987) Preparatory activity in primate motor cortex and putamen coded in spatial rather than limb coordinates. Soc Neurosci Abstr 13: 245 Google Scholar
Alstermark B, Lundberg A, Norrsell U, Sybirska E (1981) Integration in descending motor pathways controlling the forelimb in the cat. 9. Differential behavioral defects after spinal cord lesions interrupting defined pathways from higher centres to motoneurones. Exp Brain Res 42: 299–318 CASPubMed Google Scholar
Alstermark B, Kummel H, Pinter MJ, Tantisira B (1987) Branching and termination of C3-C4 propriospinal neurones in the cervical spinal cord of the cat. Neurosci Lett 74: 291–296 Google Scholar
Alstermark B, Kummel H (1986) Transneuronal labelling of neurones projecting to forelimb motoneurones in cats performing different movements. Brain Res 376: 387–391 Google Scholar
Alstermark B, Lundberg A, Sasaki S (1984a) Intergration of descending motor pathways controlling the forelimb in the cat. 11. Inhibitory pathways from higher motor centres and forelimb afferents to C3–C4 propriospinal neurones. Exp Brain Res 56: 293–307 Google Scholar
Alstermark B, Lundberg A, Sasaki S (1984b) Integration of descending motor pathways controlling the forelimb in the cat. 12. Interneurones which may mediate descending feedforward inhibition and feed-back inhibition from the forelimb to C3–C4 propriospinal neurones. Exp Brain Res 56: 308–322 Google Scholar
Asanuma H (1981) The pyramidal tract. In: Handbook of physiology. The nervous system II. American Physiological Society, Bethesda MD, pp 703–733 Google Scholar
Cochran WG, Cox GM (1957) Experimental designs, 2nd edn. Wiley, New York Google Scholar
Crutcher MD, Schwartz AB, Georgopoulos AP (1985) Representation of movement direction in primate motor cortex in the absence of immediate movement. Soc Neurosci Abstr 11: 1273 Google Scholar
Evarts EV (1981) Role of the motor cortex in voluntary movements in primates. In: Handbook of physiology. The nervous system II. American Physiological Society, Bethesda MD, pp 1083–1120 Google Scholar
Fisher NI, Lee AJ (1983) A correlation coefficient for circular data. Biometrika 70: 327–332 Google Scholar
Georgopoulos AP, Kalaska JF, Massey JT (1981) Spatial trajectories and reaction times of aimed movements: effects of practice, uncertainty, and change in target location. J Neurophysiol 46: 725–743 Google Scholar
Georgopoulos AP, Kalaska JF, Caminiti R, Massey JT (1982) On the relations between the direction of two-dimensional arm movements and cell discharge in primate motor cortex. J Neurosci 2: 1527–1537 CASPubMed Google Scholar
Georgopoulos AP, Caminiti R, Kalaska JF, Massey JT (1983) Spatial coding of movement: a hypothesis concerning the coding of movement direction by motor cortical populations. Exp Brain Res [Suppl] 7: 327–336 Google Scholar
Georgopoulos AP, Kalaska JF, Crutcher MD, Caminiti R, Massey JT (1984) The representation of movement direction in the motor cortex: single cell and population studies. In: Edelman GM, Cowan WM, Gall WE (eds) Dynamic aspects of neocortical function. Wiley, New York, pp 501–524 Google Scholar
Georgopoulos AP, Schwartz AB, Kettner RE (1986) Neuronal population coding of movement direction. Science 233: 1416–1419 CASPubMed Google Scholar
Georgopoulos AP, Massey JT (1987) Cognitive spatial-motor processes. 1. The making of movements at various angles from a stimulus direction. Exp Brain Res 65: 361–370 Google Scholar
Georgopoulos AP, Kettner RE, Schwartz AB (1988) Primate motor cortex and free arm movements to visual targets in three-dimensional space. II. Coding of the direction of movement by a neuronal population. J Neurosci 8: 2928–2937 CASPubMed Google Scholar
Georgopoulos AP, Lurito JT, Petrides M, Schwartz AB, Massey JT, (1989) Mental rotation of the neuronal population vector. Science (in press)
Godschalk M, Lemon RN, Kuypers HGJM, van der Steen J (1985) The involvement of monkey premotor cortex neurones in preparation of visually cued arm movements. Beh Brain Res 18: 143–157 Google Scholar
Howell AB, Straus WL (1983) The muscular system. In: Hartman EG, Straus WL (eds) The anatomy of the rhesus monkey. Hafner, New York, pp 89–175 Google Scholar
Humphrey DR (1979) On the cortical control of visually directed reaching: contributions by nonprecentral motor areas. In: Talbott RE, Humphrey DR (eds) Posture and movement. Raven, New York, pp 51–112 Google Scholar
Kettner RE, Schwartz AB, Georgopoulos AP (1988) Primate motor cortex and free arm movements to visual targets in three-dimensional space. III. Positional gradients and population coding of movement direction from various movement origins. J Neurosci 8: 2938–2947 Google Scholar
Kubota K, Funahashi S (1982) Direction-specific activities of dorsolateral prefrontal and motor cortex pyramidal tract neurons during visual tracking. J Neurophysiol 47: 362–376 Google Scholar
Kubota K, Hamada I (1979) Preparatory activity of monkey pyramidal tract neurons related to quick movement onset during visual tracking performance. Brain Res 168: 435–439 Google Scholar
Lamarre Y, Busby L, Spidalieri G (1983) Fast ballistic arm movements triggered by visual, auditory, and somesthetic stimuli in the monkey. I. Activity of precentral cortical neurons. J Neurophysiol 50: 1343–1358 Google Scholar
Lecas J-C, Requin J, Anger C, Vitton N (1986) Changes in neuronal activity of the monkey precentral cortex during preparation for movement. J Neurophysiol 56: 1680–1702 Google Scholar
Lundberg A (1979) Integration in a propriospinal motor centre controlling the forelimb in the cat. In: Asanuma H, Wilson VS (eds) Integration in the nervous system. Igaku-Shoin, Tokyo, pp 47–69 Google Scholar
Mountcastle VB, Talbot WH, Sakata H, Hyvarinen H (1969) Cortical neuronal mechanisms in flutter-vibration studied in unanesthetized monkeys. Neuronal periodicity and frequency discrimination. J Neurophysiol 32: 452–484 Google Scholar
Murphy JT, Kwan HC, MacKay WA, Wong YC (1982) Precentral unit activity correlated with angular components of a compound arm movement. Brain Res 246: 141–145 Google Scholar
Murphy JT, Wong YC, Kwan HC (1985) Sequential activation of neurons in primate motor cortex during unrestrained forelimb movement. J Neurophysiol 53: 435–445 Google Scholar
Phillips CG, Porter R (1977) Corticospinal neurones. Academic, New York Google Scholar
Porter R, Lewis MMc (1975) Relationship of neuronal discharges in the precentral gyrus of monkeys to the performance of arm movements. Brain Res 98: 21–36 ArticleCAS Google Scholar
Schwartz AB, Kettner RE, Georgopoulos AP (1988) Primate motor cortex and free arm movements to visual targets in three-dimensional space. I. Relations between single cell discharge and direction of movement. J Neurosci 8: 2913–2927 Google Scholar
Snedecor GW, Cochran WG (1980) Statistical methods, 7th edn. Iowa State University Press, Ames Iowa Google Scholar
Sokal RR, Rohlf FJ (1969) Biometry. Freeman, San Francisco Google Scholar
Tanji J, Evarts EV (1976) Anticipatory activity of motor cortex neurons in relation to direction of an intended movement. J Neurophysiol 39: 1062–1068 Google Scholar
Tanji J, Taniguchi K, Saga T (1980) Supplementary motor area: neuronal response to motor instructions. J Neurophysiol 43: 60–68 Google Scholar
Thach WT (1978) Correlation of neural discharge with pattern and force of muscular activity, joint position, and direction of intended next movement in motor cortex and cerebellum. J Neurophysiol 41: 654–676 Google Scholar
Weinrich M, Wise SP, Mauritz K-H (1984) A neurophysiological study of the premotor cortex in the rhesus monkey. Brain 107: 385–414 PubMed Google Scholar
Wise SP, Weinrich M, Mauritz K-H (1986) Movement-related activity in the premotor cortex of rhesus macaques. Prog Brain Res 64: 117–131 CASPubMed Google Scholar