AbstractThe purpose of the present study was to determine how humans code homologous body parts of nonhuman mammal and reptilian animals with respect to the representation of the human body. To this end, participants completed a compatibility task while viewing static images of mammalian and reptilian animals. Participants completed thumb-press or foot-pedal responses to red or blue targets, respectively, that appeared over different meerkat and lizard images in bipedal and quadrupedal postures. A head condition was added to assess any possible vertical compatibility effects. The results support the notion that the limbs of nonhuman mammalian animals are mapped onto the human body schema when the mammal is in a bipedal posture. However, an inconsistent pattern of limb compatibility effects was observed in the reptilian condition when in a bipedal posture. Finally, a nonhuman body representation is referenced when observing both nonhuman mammals and reptiles in a typical (quadrepedal) animal stance. It can be concluded that differences in body representation exist when observing mammalian and reptilian forms in both bipedal and quadrupedal postures. In addition, this pattern of results suggests that the bipedal body representation may be class-specific and lends support to the idea of a graded level of activation within the extrastriate body area associated with body plans that are similar to that of humans.
Acknowledgments: This work was supported by operating grants from the Natural Sciences and Engineering Research Council of Canada and the Ontario Ministry of Research and Innovation.