Cross‐sectional studies of IQ show young adults performing better than middle or older adults, while longitudinal studies of IQ tend to show the same people increasing in intelligence at least until their 50s. The results of the cross‐sectional studies may be due more to cohort influences:
the effects of practice, increased comfort taking such tests, and the tendency for those who remain in the studies to perform better than those who drop out.
Young adults score higher on tests of fluid intelligence, which is the ability to think abstractly and deal with novel situations, while middle adults improve over time on tests of crystallized intelligence, which involves using learned information collected throughout a life span. In summary, the results of traditional IQ tests imply that intelligence continues at approximately the same level at least into middle adulthood, and probably beyond.
Middle‐age adult thinking differs significantly from that of adolescents and young adults. Adults are typically more focused in specific directions, having gained insight and understanding from life events that adolescents and young adults have not yet experienced. No longer viewing the world from an absolute and fixed perspective, middle adults have learned how to make compromises, question the establishment, and work through disputes. Younger people, on the hand, may still look for definitive answers.
Many middle‐age adults have attained Piaget's stage of formal operations, which is characterized by the ability to think abstractly, reason logically, and solve theoretical problems. Many of the situations facing adults today require something more than formal operations. That is, the uncertain areas of life may pose problems too ambiguous and inconsistent for such straightforward thinking styles. Instead, middle adults may develop and employ postformal thinking, which is characterized by the objective use of practical common sense to deal with unclear problems. An example of postformal thinking is the middle adult who knows from experience how to maneuver through rules and regulations and play the system at the office. Another example is the middle adult who accepts the reality of contradictions in his or her religion, as opposed to the adolescent who expects a concrete truth in an infallible set of religious doctrines and rules. Postformal thinking begins late in adolescence and culminates in the practical wisdom so often associated with older adulthood.
Does intellectual development stop at age 22? Not at all. In fact, in recent years, colleges and universities have reported an increased enrollment of adult learners—students age 25 or older. Of course, labeling this age group as adult learners is not to imply that the typical college student is not also an adult. Academic institutions typically identify those outside the 18–21 range as adults, because most have been working and rearing families for some time before deciding to enter or reenter college. Compared with younger students, adult learners may also have special needs: anxiety or low self‐confidence about taking classes with younger adults, feelings of academic isolation and alienation, fears of not fitting in, or difficulties juggling academic, work, and domestic schedules.
Adults most often choose to go to college for work‐related purposes. Many employers require workers to attain certain levels of education in order to qualify for promotions. Other workers go to college to learn new skills in preparation for another career. Additionally, certain organizations, such as state licensing boards, may require professionals to have a certain number of continuing education hours each year to maintain their licenses. Finally, adults may also return to college simply for personal enrichment.
Many adults today choose distance education as their primary learning method. Numerous educational institutions offer accredited courses, certificates, and undergraduate and graduate degrees by correspondence or via alternative learning formats, such as intensive study classes conducted one weekend per month, telecourses provided over the television, or virtual classrooms set up on the Internet. Some of the programs have minimal residency requirements (time actually spent on campus); others do not, which benefits adults in rural areas who use these alternative methods to access studies that were previously unavailable to them. Adult students who successfully complete external programs tend to be highly self‐motivated and goal‐oriented.