Moreover, there is only limited information on the functional impact one region has over neurons in other regions ( 8, 9). However, little effort to date has been expended to measure the strengths of the anatomical connections. Also, based on varying levels of transported-label density in target structures, it is widely recognized that the anatomical strength of the connections between visual system components varies considerably. For example in the cat, based on functional, architectonic, and connectional features, there are 19 visual cortical areas ( 5– 7) and a number of subcortical structures that are interconnected by a large number of diverging and converging pathways ( 5– 6). The mammalian visual system consists of numerous anatomically and functionally defined cerebral cortical and subcortical components ( 1– 5). We conclude that these and future functional measures, obtained using the same combination of techniques, will furnish fundamental, new information that complements and extends current models of static cerebral networks, and lead to more realistic models of cerebral network function and component interactions. For higher processing stages, the converse holds: projections from MS cortex have stronger functional influence than predicted from the anatomy. Relative to major efferent projections from MS cortex that have a strong influence, projections to early visual processing stages have weaker functional influences than predicted from the anatomy. These functional measures were obtained by analyzing the local and distant effects of MS cooling deactivation on deoxyglucose uptake. Here, we compare the anatomically defined strengths of a set of cerebral pathways emerging from the visual middle suprasylvian (MS) cortex of the cat with measures of the functional impact the same region has over distant sites. ![]() However, measures on both magnitude and functional significance of connections are extremely limited. This static anatomical description has been pivotal in guiding our understanding of signal processing within cerebral networks. ![]() Cerebral networks are complex sets of connections that resemble a ladder-like web of multiple parallel feedforward, lateral, and feedback connections.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |