The relationship between the degree of paw preference and excitability of motor neurons innervating foreleg flexors in right- and left-preferent cats

Abstract

The relationship between the degree of paw preference and the degree of excitability of motor neurons innervating the foreleg flexor muscles was studied in unanesthetized spinal cats. The paw preference was assessed by a food-reaching test. The cats were spinalized at the first cervical segment of the spinal cord. It was found that there is an inverse relationship between the degree of H-reflex excitability and the degree of paw preference in right- and left-preferent cats. This main result was discussed with respect to functional implications and evolution of human handedness.

Key Words:

• paw preference
• spinal motor asymmetry
• motor neuron
• spinal cord
• cat