Based on theoretical analysis, in the present paper, we defined the structure of the characteristics of personality psychological maturity, which is considered an adult development criterion. The objective of this paper was to identify the mechanisms that contribute to the formation of psychological maturity in adulthood development. We first assumed that one of the possible mechanisms is the normative crisis of development. In turn, previously formed psychological maturity traits can relieve the experiences associated with this normative crisis. The aim of the present study was to analyze the formation of psychological maturity during periods of emerging and middle adulthood, with a specific focus on normative crisis experiences. The study design included cross-sectional and longitudinal methods. The participants included 309 adults. The emerging adulthood group ranged in age from 18 to 25 years, and the participants in the middle adulthood group were between 38 and 45 years of age. To study crisis events and experiences, we used three author-designed questionnaires. A self-actualization test by E. Shostrom (SAT), the Big Five personality test by Costa and MacCrae, a value and availability ratio in various vital spheres technique by E.B. Fantalova, a purpose-in-life test by D.A. Leontiev, and a coping test by Lazarus were used to define the personality characteristics used to overcome difficult life situations.

In this paper, we described experiences specific to the crises associated with emerging adulthood and middle adulthood in the context of developmental tasks. Using cluster analysis, we defined groups with different intensities of crisis experiences and analyzed psychological content of crisis experiences in different groups. Using ANOVA, we found that participants with low intensity crisis experiences show more developed characteristics of psychological maturity. During emerging adulthood, the overcoming of crises associated with the separation from family contributes to the formation of such aspects of psychological maturity as self-management, life organization and responsibility. In a longitudinal study of midlife crises, the data suggest that in groups where there are more intense crisis experiences, there are more significant dynamics in the meaning and value sphere over the course of a year that lead to the achievement of greater personal integrity and congruence.

The current study proved the hypothesis regarding the role of the crisis mechanism of psychological maturity development in two phases of adulthood. It also proved that psychological maturity contributes to a decrease in the intensity of crisis experiences.