While there is no exact consensus as to the age range of this period of life, it generally refers to the ages between approximately 40 and 60, with the lower limit sometimes placed as low as age 35 and the upper one as high as 65 years of age.
In Erik Erikson's influential scheme of human development, middle age is the period in which an individual is presented with the developmental task of choosing between ego stagnation (self-interest) and generativity, the capacity to care for others and make a positive contribution to society by being productive in work, parenting, or other activities. Carl Jung characterized the middle years as a time for self-realization and the exploration of spiritual and social values once the practical tasks of finding an occupation and establishing a family have been accomplished.
For many people, middle age is a stable period in which they are settled in a long-term love relationship, have committed themselves to a career, and have established a family and a permanent home. The middle years can also be a time of exploration and radical change, sometimes fueled by the much-publicized "midlife crisis." For some individuals, failure to achieve goals set earlier in life or reassessment of those goals may produce discontent or even despair, resulting in major lifestyle changes, both professional and personal. It is important to note that personal and professional growth at midlife may also be indicative of an individual's socioeconomic status: the poor generally have less flexibility and fewer opportunities to make sweeping changes in their lives at this stage.
The ability to realize one's full potential in middle age is also closely related to developmental experiences earlier in life. Unresolved issues of childhood and adolescence are often felt keenly during this period, and the greatest number of psychotherapy clients are thought to be of middle aged. In addition, coping with aging parents and their eventual deaths compels middle-aged individuals to acknowledge their own mortality, resulting in a restructuring of priorities. Professionally, people may change careers, return to school, or enter into business for themselves, voluntarily decreasing their earning potential or accepting a lower measure of financial security in order to pursue their dreams while they still have a chance. Some women who have stayed home to raise children often reenter the job market at midlife, a challenge that can involve major personal reassessments and lifestyle changes.
Women in midlife are confronted with the approaching end of their childbearing years and begin experiencing symptoms of menopause. Men commonly become concerned about their levels of sexual prowess and activity in middle age. Affluent, well-educated men are especially prone to engaging in extramarital affairs at this time, often with younger women. Both sexes also face the disengagement of their children, first through the detachment of adolescence, and then when the children finally leave the family home.
Anderson, Clifford. The Stages of Life: A Groundbreaking Discovery: the Steps to Psychological Maturity. New York: Atlantic Monthly Press, 1995.
Berger, Kathleen Stassen. The Developing Person Through the Life Span. 2nd ed. New York: Worth Publishers, 1988.
Inglehart, Marita Rosc. Reactions to Critical Life Events: A Social Psychological Analysis. New York: Praeger, 1991.
Zimbardo, Philip G. The Psychology of Attitude Change and Social Influence. Philadelphia: Temple University Press, 1991.