The effects of combined red nucleus and pyramidal lesions in cats

✍ Scribed by Byron H. Evans; W. R. Ingram

• Publisher: John Wiley and Sons
• Year: 1939
• Tongue: English
• Weight: 849 KB
• Volume: 70
• Category: Article
• ISSN: 0021-9967
• DOI: 10.1002/cne.900700307

✦ Synopsis

It has been reported (Ingram and Ranson, '32; Ingram, Barris and Ranson, '34) that bilateral lesions in the red nuclei or rubro-spinal tracts in cats produce a certain measure of ataxia, dysmetria, and increase in extensor tonus as determined by resistance to passive flexion, Other features are delay and hypermetria of the hopping and other postural reactions, which in some cases may even be absent for a time. Somewhat similar results, at least as to certain aspects of these findings, were previously observed by Pike, Elsberg, &IcCulloch and Chappell ( '31), and Rademaker ( '26) has ascribed the extensor rigidity of decerebration to destruction of the red nuclei. Keller and Hare ('34), on the other hand, found no alteration in extensor tonus to follow rubro-spinal lesions in the monkey, although they observed transient ataxia and tremor. I n man, lesions of the red nuclei are ordinarily held (Giacomo, '29; van Gehuchten, '33) to cause hypotonia. It should be recalled, however, that in the primates the magnocellular portion of the nucleus ruber is relatively poorly developed as compared with the small celled part, lesions of which are held to be associated with loss of tone, and Giacomo implies that involvement of the pars magnocellularis may be accompanied by hypertonia. The results of experimental lesions in the cat, which possesses a strongly developed pars magnocellularis, are quite clear-cut and have been repeatedly confirmed in a number of series of experiments. I n the course 461