Precentral projections to different parts of the spinal intermediate zone in therhesus monkey.

Summary In the cat and the rhesus monkey the descending pathways from the brain stem terminate respectively in the dorsolateral and the ventromedial parts of the spinal intermediate zone. In the rhesus monkey precentral corticospinal fibers are distributed to both these subdivisions of the intermediate zone, in addition to their distribition to the motoneuronal cell groups. An attempt has been made to clarify the differential precentral origin of the fibers to these subdivisions. In 25 rhesus monkeys lesions were made in the precentral gyrus. The distribution of the degenerating corticospinal elements was studied by means of a modified Albrecht-Fernstro¨m and the Fink-Heimer technique. The distribution of the degenerating elements was charted quantitatively. The results thus obtained indicate that in the rhesus monkey there exist two separate areas along the central sulcus that distribute their fibers primarily to the dorsolateral part of the intermediate zone, predominantly contralaterally. The intervening area along the central sulcus and the rostral parts of the precentral gyrus distribute at least a portion of their fibers to the ventromedial parts of the intermediate zone bilaterally. In addition, in the enlargements an inverse relationship was observed between the distribution of degenerating elements in the ventromedial part of the intermediate zone and the motoneuronal cell groups.

[1]  G. Brindley,et al.  The extrapyramidal cortical motor map. , 1965, Brain : a journal of neurology.

[2]  J. Petras.  Cortical, tectal and tegmental fiber connections in the spinal cord of the cat. , 1967, Brain research.

[3]  C. G. Phillips,et al.  THE PYRAMIDAL PROJECTION TO MOTONEURONES OF SOME MUSCLE GROUPS OF THE BABOON'S FORELIMB. , 1964, Progress in brain research.

[4]  R. Nyberg‐hansen.  Functional Organization of Descending Supraspinal Fibre Systems to the Spinal Cord , 1966, Ergebnisse der Anatomie und Entwicklungsgeschichte / Reviews of Anatomy, Embryology and Cell Biology / Revues d’anatomie et de morphologie expérimentale.

[5]  P Sterling,et al.  Anatomical organization of the brachial spinal cord of the cat. 3. The propriospinal connections. , 1968, Brain research.

[6]  C. Bernhard,et al.  Cortical representation and functional significance of the corticomotoneuronal system. , 1954, A.M.A. archives of neurology and psychiatry.

[7]  C. Bernhard,et al.  The localization of the premotor interneurons discharging through the peroneal nerve. , 1945, Journal of neurophysiology.

[8]  P. Sterling,et al.  Anatomical organization of the brachial spinal cord of the cat. II. The motoneuron plexus. , 1967, Brain research.

[9]  E M GLASER,et al.  A SEMI-AUTOMATIC COMPUTER-MICROSCOPE FOR THE ANALYSIS OF NEURONAL MORPHOLOGY. , 1965, IEEE transactions on bio-medical engineering.

[10]  L. Heimer,et al.  Two methods for selective silver impregnation of degenerating axons and their synaptic endings in the central nervous system. , 1967, Brain research.

[11]  D. Pandya,et al.  Interhemispheric connections of the precentral motor cortex in the rhesus monkey. , 1969, Brain research.

[12]  A. Reed.  The nuclear masses in the cervical spinal cord of Macaca mulatta , 1940 .

[13]  B. Rexed.  The cytoarchitectonic organization of the spinal cord in the cat , 1952, The Journal of comparative neurology.

[14]  H. Hoff,et al.  SPINAL TERMINATIONS OF THE PROJECTION FIBRES FROM THE MOTOR CORTEX OF PRIMATES , 1934 .

[15]  W. Chambers,et al.  An Experimental study of the cortico‐spinal system in the monkey (Macaca mulatta). The spinal pathways and preterminal distribution of degenerating fibers following discrete lesions of the pre‐ and postcentral gyri and bulbar pyramid , 1964, The Journal of comparative neurology.

[16]  H. Kuypers,et al.  Propriospinal fibers interconnecting the spinal enlargements in the cat. , 1969, Brain research.

[17]  A. Scheibel,et al.  Spinal motorneurons, interneurons and renshaw cells. A golgi studi , 1966 .

[18]  W. McCulloch.  THE FUNCTIONAL ORGANIZATION OF THE CEREBRAL CORTEX , 1944 .

[19]  E. Hoff.  CORTICOSPINAL FIBERS ARISING IN THE PREMOTOR AREA OF THE MONKEY: DISTRIBUTION OF BOUTON TERMINATIONS , 1935 .

[20]  D. G. Lawrence,et al.  Cortical projections to the red nucleus and the brain stem in the Rhesus monkey. , 1967, Brain research.

[21]  H. Kuypers,et al.  THE DESCENDING PATHWAYS TO THE SPINAL CORD, THEIR ANATOMY AND FUNCTION. , 1964, Progress in brain research.

[22]  H. Kuypers,et al.  Subcorticospinal projections in the Rhesus monkey , 1962, The Journal of comparative neurology.

[23]  C. Woolsey,et al.  Patterns of localization in precentral and "supplementary" motor areas and their relation to the concept of a premotor area. , 1952, Research publications - Association for Research in Nervous and Mental Disease.

[24]  D. G. Lawrence,et al.  The functional organization of the motor system in the monkey. II. The effects of lesions of the descending brain-stem pathways. , 1968, Brain : a journal of neurology.

[25]  M. Albrecht,et al.  A modified Nauta-Gygax method for human brain and spinal cord. , 1959, Stain technology.

[26]  H. Kuypers.  Central cortical projections to motor and somato-sensory cell groups. An experimental study in the rhesus monkey. , 1960, Brain : a journal of neurology.

[27]  P. Sterling,et al.  Simultaneous demonstration of normal boutons and degenerating nerve fibres and their terminals in the spinal cord. , 1966, Journal of anatomy.