Final answer:
The continuity theory in aging suggests that older adults strive to maintain consistency in internal and external structures to preserve stability. It is contrasted with theories like disengagement theory, but faces criticism for overlooking those with chronic illnesses.
Step-by-step explanation:
The continuity theory implies maintenance of consistency in internal structures, such as personality and beliefs, and external structures, including relationships. Seniors are believed to actively choose to engage in activities and roles that are consistent with their prior experiences to maintain this consistency, perhaps to a greater degree, compared to other theories of aging such as disengagement theory. The continuity theory promotes the idea that maintaining established roles and activities contributes to social equilibrium and personal stability as one ages.
However, criticism arises due to the theory's tendency to focus on so-called "normal" aging, which may ignore or marginalize the experiences of older adults with chronic illnesses, such as Alzheimer's, who might not be able to maintain these consistencies.