| Popis: |
The octopus is an active predator with a highly flexible body and a rich behavioral repertoire. It d isplays advanced cognitive abilities, and the size of its large nervous system rivals that of many mammals. However, only one third of the neurons comprise the CNS, while the rest are located in an elaborate PNS, including eight arms, each of which contain s myriad sensory receptors of various modalities. This organization led early workers to question the extent to which the CNS is privy to non - visual sensoryinput from the periphery, and to suggests that the octopus brain has little or no capacity to finely control arm movement. We recently demonstrated that octopuses use visual information to control goal - directed complex movements of single arms. However, that study did not establish whether animals use information from the arm itself. We here report on de velopment of two - choice, single arm mazes which test the ability of an octopus to perform operant learning tasks that mimic normal octopus tactile exploration behavior, and that require the CNS to use pertinent sensory information from single arms. We show that the brain of the octopus uses peripheral information about arm motion as well as tactile input to accomplish learning tasks that entail directed control of movement. We conclude that although the arms of this cephalopod have a great capacity to act i ndependently, they also are subject to considerable central control, allowing for well organized, purposeful behavior of the organism as a whole. |
