Final answer:
The Sigma pattern is the personality prototype introduced in Millon's 2011 updates and included for the first time in the MCMI-IV.
Step-by-step explanation:
The personality prototype introduced in Millon's 2011 updates to the theory and included for the first time in the Millon Clinical Multiaxial Inventory-IV (MCMI-IV) is the Sigma pattern. Theodore Millon's theories on personality disorders and assessments have been influential in the field of psychology. The MCMI-IV is a psychological assessment tool used to diagnose personality disorders, and the addition of the Sigma pattern reflects updates and refinements to Millon's theoretical framework. This pattern is described as comprising adaptive self-perception and interpersonal relations, with individuals seen as self-sufficient and capable of high functioning.