[The hypercolumns of the guinea pig visual cortex. The heterogeneity and multilevel topical organization of the...

Spatial distribution of neural responses to spots, slits, and bars in the guinea pig visual cortex reveals hypercolumns like those in the brain of higher mammals. The regular heterogeneities of topic projections within and between hypercolumns (reflected in a distribution of focal potentials in different cortical areas) suggest that the described columns are discrete cortical zones (or macromodules) about 0.6 mm in size. They consist of 7-10 on/off polar orientation micromodules about 0.2 mm in size. In turn, the latter also have the inner topical organization of their projections. Consequently, the described topical projections have a multilevel hierarchical organization of accordance with different complicity of neural structures. Taking into account the known polar structure of hypercolumns we think that it provides a possibility of comparison between the vectors of signals and polar structures. There are reasons to believe that this is a principle condition for signal recognition.