is the study of the social, psychological and biological aspects
of aging. It is distinguished from geriatrics, which is the
branch of medicine that studies the diseases of older adults.
Gerontologists include researchers and practitioners in the
fields of biology, medicine, optometry, dentistry, social work,
physical and occupational therapy, psychology, psychiatry,
sociology, economics, political science, architecture, pharmacy,
nursing public health, housing and anthropology.
Gerontology encompasses the following:
studying physical, mental, and social changes in people as they
age investigating the aging (ageing) process itself (biogerontology)
investigating the interface of normal aging and age-related
investigating the effects of an ageing population on society
applying this knowledge to policies and programs, including the
macroscopic (for example, government planning) and microscopic
(for example, running a nursing home) perspectives.
The multidisciplinary nature of gerontology means that there are
a number of subfields, as well as associated fields such as
psychology and sociology that overlap with gerontology.
Gerontologists view aging in terms of four distinct processes:
chronological aging, biological aging, psychological aging, and
social aging. Chronological aging is the definition of aging
based on a person's years lived from birth. Biological aging
refers to the physical changes that reduce the efficiency of
organ systems. Psychological aging includes the changes that
occur in sensory and perceptual processes, cognitive abilities,
adaptive capacity, and personality. Social aging refers to an
individual's changing roles and relationships with family,
friends, and other informal supports, productive roles and