The organization of the corticocortical projection of area 5 upon area 7 in the parietal lobe of the monkey.

The distribution of labelled cells and of extracellular granules in the cortex of area 5 of the parietal lobe of the monkey has been studied after injections of horseradish peroxidase into area 7. Area 5 is related only to area 7b (PF) and not to area 7a (PG). The corticocortical connections between area 5 and 7b are reciprocal and well organized so that the same representations in each area are interconnected. No corticocortical fibres pass between areas 7a (PG) and 7b (PF).