Skip to main content
PMC home page
Proceedings of the Royal Society B: Biological Sciences logoLink to Proceedings of the Royal Society B: Biological Sciences
. 1999 Apr 22;266(1421):853–857. doi: 10.1098/rspb.1999.0715

Changes in posture alter the attentional demands of voluntary movement.

R G Carson 1, R Chua 1, W D Byblow 1, P Poon 1, C J Smethurst 1
PMCID: PMC1689907  PMID: 10343408

Abstract

Two simple experiments reveal that the ease with which an action is performed by the neuromuscular-skeletal system determines the attentional resources devoted to the movement. Participants were required to perform a primary task, consisting of rhythmic flexion and extension movements of the index finger, while being paced by an auditory metronome, in one of two modes of coordination: flex on the beat or extend on the beat. Using a classical dual-task methodology, we demonstrated that the time taken to react to an unpredictable visual probe stimulus (the secondary task) by means of a pedal response was greater when the extension phase of the finger movement sequence was made on the beat of the metronome than when the flexion phase was coordinated with the beat. In a second experiment, the posture of the wrist was manipulated in order to alter the operating lengths of muscles that flex and extend the index finger. The attentional demands of maintaining the extend-on-the-beat pattern of coordination were altered in a systematic fashion by changes in wrist posture, even though the effector used to respond to the visual probe stimulus was unaffected.

Full Text

The Full Text of this article is available as a PDF (118.0 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Blinkenberg M., Bonde C., Holm S., Svarer C., Andersen J., Paulson O. B., Law I. Rate dependence of regional cerebral activation during performance of a repetitive motor task: a PET study. J Cereb Blood Flow Metab. 1996 Sep;16(5):794–803. doi: 10.1097/00004647-199609000-00004. [DOI] [PubMed] [Google Scholar]
  2. Carson R. G. Neuromuscular-skeletal constraints upon the dynamics of perception-action coupling. Exp Brain Res. 1996 Jun;110(1):99–110. doi: 10.1007/BF00241379. [DOI] [PubMed] [Google Scholar]
  3. Carson R. G., Riek S. The influence of joint position on the dynamics of perception-action coupling. Exp Brain Res. 1998 Jul;121(1):103–114. doi: 10.1007/s002210050442. [DOI] [PubMed] [Google Scholar]
  4. Cheney P. D., Fetz E. E., Mewes K. Neural mechanisms underlying corticospinal and rubrospinal control of limb movements. Prog Brain Res. 1991;87:213–252. doi: 10.1016/s0079-6123(08)63054-x. [DOI] [PubMed] [Google Scholar]
  5. Dettmers C., Fink G. R., Lemon R. N., Stephan K. M., Passingham R. E., Silbersweig D., Holmes A., Ridding M. C., Brooks D. J., Frackowiak R. S. Relation between cerebral activity and force in the motor areas of the human brain. J Neurophysiol. 1995 Aug;74(2):802–815. doi: 10.1152/jn.1995.74.2.802. [DOI] [PubMed] [Google Scholar]
  6. Duncan J., Martens S., Ward R. Restricted attentional capacity within but not between sensory modalities. Nature. 1997 Jun 19;387(6635):808–810. doi: 10.1038/42947. [DOI] [PubMed] [Google Scholar]
  7. Gordon A. M., Huxley A. F., Julian F. J. The variation in isometric tension with sarcomere length in vertebrate muscle fibres. J Physiol. 1966 May;184(1):170–192. doi: 10.1113/jphysiol.1966.sp007909. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Kelso J. A., Fuchs A., Lancaster R., Holroyd T., Cheyne D., Weinberg H. Dynamic cortical activity in the human brain reveals motor equivalence. Nature. 1998 Apr 23;392(6678):814–818. doi: 10.1038/33922. [DOI] [PubMed] [Google Scholar]
  9. Ketchum L. D., Thompson D., Pocock G., Wallingford D. A clinical study of forces generated by the intrinsic muscles of the index finger and the extrinsic flexor and extensor muscles of the hand. J Hand Surg Am. 1978 Nov;3(6):571–578. doi: 10.1016/s0363-5023(78)80008-2. [DOI] [PubMed] [Google Scholar]
  10. Lee T. D., Blandin Y., Proteau L. Effects of task instructions and oscillation frequency on bimanual coordination. Psychol Res. 1996;59(2):100–106. doi: 10.1007/BF01792431. [DOI] [PubMed] [Google Scholar]
  11. Lemon R. The output map of the primate motor cortex. Trends Neurosci. 1988 Nov;11(11):501–506. doi: 10.1016/0166-2236(88)90012-4. [DOI] [PubMed] [Google Scholar]
  12. Nathan R. H. The isometric action of the forearm muscles. J Biomech Eng. 1992 May;114(2):162–169. doi: 10.1115/1.2891367. [DOI] [PubMed] [Google Scholar]
  13. Schieber M. H., Hibbard L. S. How somatotopic is the motor cortex hand area? Science. 1993 Jul 23;261(5120):489–492. doi: 10.1126/science.8332915. [DOI] [PubMed] [Google Scholar]
  14. Schlaug G., Sanes J. N., Thangaraj V., Darby D. G., Jäncke L., Edelman R. R., Warach S. Cerebral activation covaries with movement rate. Neuroreport. 1996 Mar 22;7(4):879–883. doi: 10.1097/00001756-199603220-00009. [DOI] [PubMed] [Google Scholar]
  15. Vallbo A. B., Wessberg J. Organization of motor output in slow finger movements in man. J Physiol. 1993 Sep;469:673–691. doi: 10.1113/jphysiol.1993.sp019837. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the Royal Society B: Biological Sciences are provided here courtesy of The Royal Society

RESOURCES