[An organizational analysis of the neurons forming the descending cortico-hypothalamic pathways]

Quantitative assessment of spatial organization of cortical neurons forming descending fibre systems and hypothalamic structures has been made using technique of retrograde axonal transport of horseradish peroxidase. Heterogeneity of cortico-hypothalamic bonds is determined: the prefrontal cortex exerts a more pronounced effect on the hypothalamus as compared with other cortical areas of the limbic brain. Cortico-hypothalamic neurons form neuronal groups on different frontal levels of the prefrontal cortex and convolution of the cingulum, a form and orientation of the group being determined by the topography of dominating axonal systems running to the hypothalamus. There are various forms of cell associations in the frames of neuronal populations. Ensemble groupings of neurons may underlie the principle of organization of direct cortico-hypothalamic ways.