The formation of lateralized motor habits in rats.

Wistar rats were trained to obtain food from a narrow tube feeder using the forepaw in conditions of free choice of which limb to use. It was found that the presence or absence of limb preference, identified in short preliminary tests, often did not coincide with the nature and degree of lateralization formed during the process of prolonged training. Achievement of the maximum degree of lateralization by the animals finally forming the right-handed group was found to require longer average training periods than was the case for left-handed rats.