What is Overlap?

Overlap is the process of leading someone from their preferred representation system to a less preferred representation system. For example,  “I can’t do pictures”, “Ok, Imagine you are standing on a beach, and feel the sand against your feet, hear the water lapping against the shore, listen to the birds overhead, and now look up, and notice if you can now, imagine you can see the birds”

See also What is the Primary Representation System?, Predicates, What is NLP?