Show Summary Details
Page of

The Motor Cortical Areas and Descending Pathways 

The Motor Cortical Areas and Descending Pathways
Chapter:
The Motor Cortical Areas and Descending Pathways
Author(s):

Per Brodal

DOI:
10.1093/med/9780190228958.003.0022
Page of

PRINTED FROM OXFORD MEDICINE ONLINE (www.oxfordmedicine.com). © Oxford University Press, 2021. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use (for details see Privacy Policy and Legal Notice).

date: 01 March 2021

Chapter 22 deals with the control of complex, purposeful movements. The most direct control is exerted by upper motor neurons in the cerebral cortex, forming the pyramidal tract that is indispensable precise finger movements. The corticoreticulospinal pathways are important for fairly crude, stereotyped voluntary movements of the extremities. Rhythm generators in the spinal cord and the brain stem control locomotion and respiration. Supraspinal control of locomotion depends on a mesencephalic locomotor region (MLR). Motor cortical areas, notably the primary motor area (MI), the premotor area (PMA), and the supplementary motor area (SMA) are also discussed. The MI gives origin to a large part of the pyramidal tract fibers. The PMA and SMA act largely by “instructing” the MI what to do. The final part of the chapter deals with symptoms resulting from damage to the central motor pathways. Main characteristics of central pareses are hyperreflexia (spasticity) and loss of dexterity.

Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription.

Please subscribe or login to access full text content.

If you have purchased a print title that contains an access token, please see the token for information about how to register your code.

For questions on access or troubleshooting, please check our FAQs, and if you can't find the answer there, please contact us.