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PSY 101 ![]() |
Adolescence
1. Physical Changes of Adolescence
Puberty: the maturation of sexual functions
- Males: between 11 and 16 years old
- Females: between 10 and 15 years old
- Both males and females today are reaching sexual maturity (puberty) at a younger age than those who grew up in the 19th and early 20rh centuries.
- This phenomenon may be due to better diet and medical care. It also may be due to environmental exposure to "endocrine disruptors" (chemicals)
- which speed up the onset of puberty.
- Early maturation in girls and late maturation in boys is associated with self-consciousness about looks
- Early maturation in both girls & boys is associated with increased alcohol/drug use, risky behaviors, and trouble with law
- Early maturing girls do more poorly academically; have earlier intercourse, higher risk for eating disorders
Primary Sexual Characteristics = the structures necessary for reproduction
- Males: penis, testes
- Sperm produced in US males ca. 14 years old
- Females: ovaries, vagina, uterus
- Onset of menstruation in females = menarche (in US ca. 12.5 years old)
Neural Development
After early school age, the size of the brain overall doesn't change much (Bava & Tapert, 2010). But processes of maturation – especially in the prefrontal cortex, limbic system, and longer distance connection fibers – continue throughout adolescence.
- The brain's grey matter (neurons) reaches its peak number at ca. 12-14 years old and then the number declines.
- However, the brain's white matter (myelin-covered axons) increases (becomes more plentiful) particularly in the fronto-parietal areas. The combination of these processes indicates that synaptic pruning, eliminating less-efficient or used synapses, is going on and the most used network of neurons is strengthening.
- Further, the maturation of the prefrontal cortex, intimately involved in executive control, judgment, and planning, continues to about 25 years old.
- The lack of maturation, however, cannot be the sole cause for risky behaviors by adolescents. Rather, teens who spend much of their time with peers seem to be much more likely to take risks when peers are present rather than when they are not. This is not true for adults.
3. Identity Development in Late Adolescence
- Erik Erikson argued that the central struggle of adolescence is Identity vs. Role Confusion
- Identity = a stable sense of your own individuality including a cohesive set of values and beliefs about morality, political orientation, religious issues, etc.
- The absence of identity (confusion) has been associated with problematic behaviors among adolescents such as substance abuse, unprotected sexual activity, anxiety, etc.
A more elaborate and contemporary version of Erikson's thesis was developed by the Canadian psychologist, James E. Marcia, and describes late adolescents (roughly ages 16-22). See the chart below.
- Are there people or characters in the media (TV, movies, etc.) who seem like they fulfill any of these four types of identity development?
The concept of the "Adult Transition" or "Emerging Adulthood" as a distinct period in Western culture has begun to get more and more attention in the last decade (see Arnett, 2014; Arnett et al. 2014).
Identity Achievement Know what they want to do and have or are taking steps to do it Identity Foreclosure
Know what they want to do and have for a long time because they are going to do what others like their parents have told them what to do Identity
MoratoriumDon't know right now exactly what they will be doing, but are continuing their education or otherwise doing something temporarily until they can commit themselves to further training and/or action Identity
DiffusionDon't know what they want or will be doing in the future, don't care that they don't know, and are doing nothing to remedy the absence of any future direction
- From ages 18/19 through roughly 27/28 years old, individuals have generally not settled down yet as independent. Increasing numbers of emerging adults are still living at home or continue in graduate school
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Characteristics of this period include
- Identity exploration: Individuals are exploring and trying out different solutions in both their work settings and love relationships. Career pathways are generally given greater priority than getting married. The average age of marriage is increasing. Now in the late 20s.
- Sense of instability (the flip side of explorations) in both love and work. Multiple changes in jobs (average number of different jobs in decade after high school graduation is 7). Lack of certitude is often reflected in the affective responses of emerging adults, e.g., 60% of people in their 20s describe themselves as "anxious" and 40% as "depressed" from time to time (Arnett et al, 2014).
- Focus upon the self: for many this is the period with the lowest number of social roles and commitments.
- Feeling "in between" adolescence and full adulthood (not still adolescent, not yet adult).
- Possibilities & Optimism: Despite the "Great Recession" of 2008, research in the early 2010s shows a strikingly high positive outlook in this age group.
- What will happen because of 2020s coronavirus pandemic is gradually becoming clear:
- Higher levels of mental health issues (ca. 50% of 18-24 yo report anxiety or depression)
- Greater feelings of being emotionally "stuck" including lowered levels of motivation, problems in social interactions, and avoiding new responsiblities
- In communities of color, much higher levels of economic insecurity and disproportionate job loss.
Adulthood1. Personality Development
- How similar is our personality (does it change?) across the years of adulthood?
- Research suggests that there is BOTH stability and changes in personality across the adult years.
- When we compare adults to other adults, personality trait scores as measured on tests tend to remain at about the same relative levels (i.e., the same percentiles vis-a-vis other adults of the same age) as we get older.
- However, when looking at fundamental traits (the Big 5: Extraversion vs. Introversion, Neuroticism, Agreeableness, Openness to Experience, and Conscientiousness) there ARE changes that appear across adulthood
- Adults tend to remain relatively stable on the trait of extraversion vs. introversion.
- Adults tend to become more agreeable and and conscientious as they get older while neuroticism grows less.
- There are conflicting findings about openness to experience: some researchers see a steady though small decline wiht age while others see an increase through middle age and a decline in older age.
- Changes in personality are more widely seen in the period from roughly age 20 to age 40. For example, levels of conscientiousness tend to grew significantly during a person's 20s.
- Erikson's Three Stages in Adulthood
- Intimacy vs. Isolation (early to late 20s): The challenge is to be able to enter into an intimate relationship with another adult. Otherwise, an individual may experience an enduring sense of isolation. In society traditionally this has meant marriage.
- Generativity vs. Self-absorption (late 20s-mid-50s): As middle adults, the psychosocial task is to shape the future generation in multiple ways: raising and guiding young children into their own adulthood, contributing to the well-being of the world via one's job (teaching, inventing, producing, nurturing, caring for the sick, etc.). On the other hand, a failure to be generative finds an adult as self-absorbed, selfish, concerned with his/her own needs and desires.
- Integrity vs. Despair (after the mid-50s into old age): Older adults, particularly those who have "retired" from the work of their middle age and whose children are now themselves adults, look back and assess what they have achieved in life and how life "fits together." Was life "worth it"? Did I make a contribution? Can I continue to find meaning and satisfaction in my life or do I become bitter, resentful, and feeling like a complete failure?
2. Life Transitions in Adulthood
- Adjusting to Marriage
- Careers: whose is more important - the man's or the woman's? Often, men see their careers are more important.
- Who does the household work? 2/3 is still done by women
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- Adjusting to Parenthood
- Impact of child's birth is heavier on women. About 10-20% experience postpartum depression. There tends to be a decline in marital satisfaction with the arrival of the new child.
- Parents experience greater impact upon children when they are younger, much less so when they are adolescents.
- Adjusting to the "Empty Nest"
- With the increase in women working, the sense of "empty nest" is far less now than previously.
- The return of adult children to the home can itself be much more stressful on the parents.
3. Aging
Physical Changes
- Decline in visual & auditory acuity
- Sensitivity to color and color contrast decreases
- After 60, amount of brain tissue & weight decreases & this is NORMAL
- Increased rates of dementia (multiple cognitive problems, esp. memory). Over 75 years, dementia rate is 15-20% and over 85 years is at least 40%.
- Primary form of dementia is Alzheimer's disease which begins with memory loss. However, this leads to complete disorientation and, gradually, the inability to take care of self over the course of 7-10 years.
- Cognitive Changes
- Overall intelligence remains relatively stable (only a slight decline after age 60)
- Memory capabilities appear to decrease, especially regarding episodic (autobiographical/event) & working memory [less loss of procedural ("how to") & semantic ("fact") memory].
- Cognitive problems are first manifested by decreased speed: longer to learn, solve problems, process information.
- HOWEVER, given sufficient time, ability to solve problems does not decrease in absolute terms. Give an older adult enough time and he/she usually can do as well as a younger adult on most intellectual tasks.
- Research by Verissimo et al. (2021) notes: "Older adults have been found to outperform younger adults in other domains … [including] ‘wisdom’, theory of mind, emotional regulation, aspects of decision-making abilities, motivation related to one’s job, and certain dimensions of personality such as agreeableness and conscientiousness" (p. 1)
- Further: We tested ageing effects on the alerting, orienting and executive (inhibitory) networks posited by Posner and Petersen’s influential theory of attention, in a cross-sectional study of a large sample (N = 702) of participants aged 58–98. Linear and nonlinear analyses revealed that whereas the efficiency of the alerting network decreased with age, orienting and executive inhibitory efficiency increased, at least until the mid-to-late 70s. [Abstract]
-attentional network => decreased vigilance & preparedness to respond to incoming information, but...
-orienting network => increased selection of information from sensory inputs by shifting from previous processing
-executive network => increased inhibition, that is, actually detecting conflict and inhibiting distracting or conflicting information
Arnett, J. J. (2014). Emerging Adulthood: The Winding Road from the Late Teens through the Twenties (2nd ed.). New York, NY: Oxford University Press.References
Arnett, J. J., Žukauskienė, R., & Sugimura, K. (2014). The New Life State of Emerging Adulthood at Ages 18-29 Years: Implications for Mental Health. Lancet Psychiatry, 1, 569-576.
Marcia, J. E., (1966). Development and validation of ego identity status. Journal of Personality and Social Psychology, 3, 551-558.
Veríssimo, J., Verhaeghen, P., Goldman, N. et al. (2021). Evidence that ageing yields improvements as well as declines across attention and executive functions. Nature Human Behavior. https://doi.org/10.1038/s41562-021-01169-7
This page was originally posted on 10/10/03 and last updated on Sept. 1, 2025