Plasticity and primary motor cortex

• Published in: Annual review of neuroscience 2000-01, Vol.23 (1), p.393-415
• Main Authors: SANES, J. N, DONOGHUE, J. P
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cognition - physiology; Fundamental and applied biological sciences. Psychology; Humans; Learning - physiology; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Motor Cortex - physiology; Neural Pathways - physiology; Neuronal Plasticity - physiology; Vertebrates: nervous system and sense organs
• ISSN: 0147-006X; 1545-4126
• DOI: 10.1146/annurev.neuro.23.1.393

One fundamental function of primary motor cortex (MI) is to control voluntary movements. Recent evidence suggests that this role emerges from distributed networks rather than discrete representations and that in adult mammals these networks are capable of modification. Neuronal recordings and activation patterns revealed with neuroimaging methods have shown considerable plasticity of MI representations and cell properties following pathological or traumatic changes and in relation to everyday experience, including motor-skill learning and cognitive motor actions. The intrinsic horizontal neuronal connections in MI are a strong candidate substrate for map reorganization: They interconnect large regions of MI, they show activity-dependent plasticity, and they modify in association with skill learning. These findings suggest that MI cortex is not simply a static motor control structure. It also contains a dynamic substrate that participates in motor learning and possibly in cognitive events as well.