Biological theories of aging focus on the cellular and molecular changes that occur in the body over time and how these changes contribute to the aging process.

The Error Catastrophe Theory proposes that aging occurs due to the accumulation of errors in DNA replication, leading to a decline in cellular function and an increased risk of disease.

The Free Radical Theory suggests that aging is caused by the accumulation of free radicals, which are unstable molecules that can damage cells and tissues.

Psychological theories of aging focus on the role of psychological factors, such as personality, coping mechanisms, and social support, in influencing the aging process.

The Cognitive Decline Theory proposes that aging is characterized by a decline in cognitive abilities, such as memory, attention, and problem-solving skills.

Social theories of aging focus on the role of social factors, such as social support, social networks, and social norms, in influencing the aging process.

The Disengagement Theory proposes that aging is characterized by a gradual withdrawal from social activities and roles, as individuals adapt to the changes associated with aging.

The Activity Theory suggests that aging is best managed by maintaining social engagement and activity, as these factors can contribute to a sense of purpose and well-being.

The Continuity Theory proposes that aging is best managed by maintaining a sense of continuity and consistency in one's life, including social roles, activities, and relationships.

Disability Theory focuses on the role of disability in the aging process, including the social, economic, and cultural factors that influence the experience of disability in later life.

Disability Studies Theory emphasizes the importance of understanding the lived experiences of people with disabilities, including the social, cultural, and political factors that shape their experiences.

Policy Theory focuses on the role of social policies and programs in addressing the needs of older adults with disabilities, including the development and implementation of policies that promote equity and inclusion.

Interdisciplinary Theory emphasizes the importance of interdisciplinary approaches to understanding and addressing the challenges of aging and disability, drawing on insights from multiple disciplines to develop comprehensive and effective solutions.

Intersectionality Theory emphasizes the importance of considering the intersectionality of aging and disability with other social identities and experiences, such as race, gender, class, and sexual orientation, to understand the unique challenges and opportunities faced by individuals.