Hemispheric asymmetry of the space-motion component of a food-conditioned motor reflex

The preference of movement direction in the process of motor food conditioned reaction has been investigated in rats with intact brain and after unilateral cortical inactivation. It was shown that the degree of motorspatial preference diminished with the maturation of reaction. At the high level of differentiation the valid preference was shown only in 38% of animals investigated but it was absent in the rest of animals. After inactivation of right hemisphere cortex left-side preference occurred in the presence as well as in the absence of the original preference. Inactivation of the left hemisphere cortex is less significant; it influences the original preference of movement direction permanently affecting those animals which normally had evident preference. It is concluded that the right hemisphere cortex plays dominant part in both sensor and motorspatial components of motor food conditioned reaction. It is supposed that the definite relationship exists between the degree of preference of movement direction and the functional asymmetry of cerebral hemispheres.