Final answer:
Jeffrey Jensen Arnett is the psychologist associated with the concept of emerging adulthood, describing a phase from 18 to the mid-20s when individuals experience extended transitions into adult responsibilities.
Step-by-step explanation:
The psychologist most prominently associated with the idea of emerging adulthood is Jeffrey Jensen Arnett. Arnett's groundbreaking concept, proposed in his 2000 paper, describes emerging adulthood as a distinct period of life from approximately 18 to the mid-20s where young people are granted an extended transition into adult roles. This reflects a global shift wherein young adults now take longer to achieve traditional markers of adulthood such as stable employment, financial independence, marriage, and starting a family.
Several factors contribute to this new stage, including longer life expectancy, higher educational demands, and shifting cultural expectations. In more industrialized societies, there is a trend where young adults pursue higher education, leading to delayed entry into the workforce and therefore a postponement of financial and familial independence. This transition period allows for exploration and delayed commitment in areas such as work and relationships, which is indicative of the changes observed in population demographics and socio-economic structures of developed nations. Arnett's theory suggests that emerging adulthood is a unique period where individuals explore various life possibilities and gradually ease into adult responsibilities.