Study of capability for recognition of complex visual stimuli of different quantities in the lower monkeys

Capability of monkeys for identification of quantitative signs has been studied at recognition and comparison of two-and three-dimensional objects in quantities from 1 to 8. The work was carried out on two species of the lower monkeys: rhesus macaque (Macaca mulatto) and brown capuchins (Cebus apella). The studied representatives of the monkeys have been established to be able to differentiate planar images and casts of cherries in various quantity combinations from 1 to 8 and to identify identical signs of visual stimuli. The obtained data indicate the ability of monkeys to abstract and to form preverbal notions of quantitative signs of objects.