Search for a common neurocognitive mechanism for language and movements.

Examination of the common properties in the three Ss (i.e., speech, script, and sign languages) of human communication suggests that duality of patterning is the key feature in the development of these communication systems. This feature is in essence a sequential strategy that serves as an interface between the increasing number of messages and the limited capacity of our signal production-reception systems. It is argued that since the left hemisphere has a much finer temporal resolution than the right hemisphere, both language and movement systems might have made use of this advantage provided by the left hemisphere to fulfill the requirements of sequential strategy in their early evolution.