1.3 Age and Periods of Human Development
Learning Objectives
- Differentiate conceptions of age
- Describe the basic periods of human development
Conceptions of Age
Lifespan vs. Life expectancy
At this point you must be wondering what the difference between lifespan and life expectancy is, according to developmentalists. Lifespan, or longevity, refers to the maximum age any member of a species can reach under optimal conditions. For instance, the grey wolf can live up to 20 years in captivity, the bald eagle up to 50 years, and the Galapagos tortoise over 150 years (Smithsonian National Zoo, 2016). The longest recorded lifespan for a human was Jean Calment who died in 1994 at the age of 122 years, 5 months, and 14 days (Guinness World Records, 2016). Life expectancy is the average number of years a person born in a particular time period can typically expect to live (Vogt & Johnson, 2016).
How old are you?
Chances are you would answer that question based on the number of years since your birth, or what is called your chronological age. Ever felt older than your chronological age? Some days we might “feel” like we are older, especially if we are not feeling well, are tired, or are stressed out. We might notice that a peer seems more emotionally mature than we are, or that they are physically more capable. So years since birth is not the only way we can conceptualize age.
Biological age
Another way developmental researchers can think about the concept of age is to examine how quickly the body is aging, this is your biological age. Several factors determine the rate at which our body ages. Our nutrition, level of physical activity, sleeping habits, smoking, alcohol consumption, how we mentally handle stress, and the genetic history of our ancestors, to name but a few.
Psychological age
Our psychologically adaptive capacity compared to others of our chronological age is our psychological age. This includes our cognitive capacity along with our emotional beliefs about how old we are. An individual who has cognitive impairments might be 20 years of age, yet has the mental capacity of an 8-year-old. A 70- year-old might be travelling to new countries, taking courses at college, or starting a new business. Compared to others of our age group, we may be more or less active and excited to meet new challenges. Remember you are as young or old as you feel.
Social age
Our social age is based on the social norms of our culture and the expectations our culture has for people of our age group. Our culture often reminds us whether we are “on target” or “off target” for reaching certain social milestones, such as completing our education, moving away from home, having children, or retiring from work. However, there have been arguments that social age is becoming less relevant in the 21st century (Neugarten, 1979; 1996). If you look around at your fellow students at college you might notice more people who are older than traditional aged college students, those 18 to 25. Similarly, the age at which people are moving away from the home of their parents, starting their careers, getting married or having children, or even whether they get married or have children at all, is changing.
Those who study lifespan development recognize that chronological age does not completely capture a person’s age. Our age profile is much more complex than this. A person may be physically more competent than others in their age group, while being psychologically immature. So, how old are you?
Periods of Human Development
Think about the lifespan and make a list of what you would consider the basic periods of development. How many periods or stages are on your list? Perhaps you have three: childhood, adulthood, and old age. Or maybe four: infancy, childhood, adolescence, and adulthood. Developmentalists often break the lifespan into eight stages, described in Table 1.2.
Table 1.2 Age Periods of Development
| Age Period | Description |
| Prenatal | Starts at conceptions, continues through implantation in the uterine wall by the embryo, and ends at birth. |
| Infancy and Toddlerhood | Starts at birth and continues to two years of age. |
| Early Childhood | Starts at two years of age until six years of age. |
| Middle and Late Childhood | Starts at six years of age and continues until the onset of puberty. |
| Adolescence | Starts at the onset of puberty until 18 |
| Emerging Adulthood | Starts at 18 until 25. |
| Early Adulthood | Starts at 25 until 40-45. |
| Late Adulthood | Starts at 65 onward. |
adapted from Lally & Valentine-French, 2019
In addition, the topic of “Death and Dying” is usually addressed after late adulthood since overall, the likelihood of dying increases in later life (though individual and group variations exist). Death and dying will be the topic of our last module, though it is not necessarily a stage of development that occurs at a particular age.
Table 1.2 shows the developmental periods that will be explored in this book, starting with prenatal development and continuing thought late adulthood. Both childhood and adulthood are divided into multiple developmental periods. So, while both an 8-month old and an 8-year-old are considered children, they have very different motor abilities, social relationships, and cognitive skills. Their nutritional needs are different and their primary psychological concerns are also distinctive. The same is true of an 18-year-old and an 80-year-old, even though both are considered adults.
Prenatal Development
Conception occurs and development begins. All of the major structures of the body are forming, and the health of the mother is of primary concern. Understanding nutrition, teratogens, or environmental factors that can lead to birth defects, and labor and delivery are primary concerns.
Infancy and Toddlerhood
The first two years of life are ones of dramatic growth and change. A newborn, with a keen sense of hearing but very poor vision, is transformed into a walking, talking toddler within a relatively short period of time. Caregivers are also transformed from someone who manages feeding and sleep schedules to a constantly moving guide and safety inspector for a mobile, energetic child.
Early Childhood
This period is also referred to as the preschool years and consists of the years that follow toddlerhood and precede formal schooling. As a two to six-year-old, the child is busy learning language, gaining a sense of self and greater independence, and beginning to understand the workings of the physical world.
Middle and Late Childhood
The ages of six to the onset of puberty comprise middle and late childhood, and much of what children experience at this age is connected to their involvement in the early grades of school. Now the world becomes one of learning and testing new academic skills, and assessing one’s abilities and accomplishments by making comparisons between self and others.
Adolescence
Adolescence is a period of dramatic physical change marked by an overall growth spurt and sexual maturation, known as puberty. It is also a time of cognitive change as the adolescent begins to think of new possibilities and to consider abstract concepts such as love, fear, and freedom. At the same time, adolescents have a sense of invincibility that puts them at greater risk of accidents or contracting sexually transmitted infections that can have lifelong consequences.
Emerging Adulthood
The period of emerging adulthood is a transitional time between the end of adolescence and before individuals acquire all the benchmarks of adulthood. Continued identity exploration and preparation for full independence from parents are negotiated. Although at one’s physiological peak, emerging adults are most at risk for involvement in violent crimes and substance abuse.
Early Adulthood
The twenties and thirties are identified as early adulthood. Intimate relationships, establishing families (of all shapes and sizes), and work are primary concerns at this stage of life. For adults with children, developmental changes can become organized around the family life cycle.
Middle Adulthood
The forties through the mid-sixties are referred to as middle adulthood. This is a period in which aging becomes more noticeable and when many people are at their peak of productivity in love and work. At this age, some people are negotiating adolescent children and aging parents at the same time.
Watch It: The UP Series
In 1964, researchers and filmmakers began a fascinating and landmark documentary series known as the UP Series. The UK-based World in Action team, inspired by the Jesuit maxim, “Give me the child until he is seven and I will give you the man,” interviewed a diverse group of seven-year-old children from all over England. In the first film, called “Seven Up!,” they asked seven-year-old children about their lives, dreams, and fears for the future. Michael Apted, a researcher for the original film, has returned to interview these individuals every seven years since then, at ages 14, 21, 28, 35, 42, 49, 56, and finally at age 63.
This video gives a nice overview of the series (through the lens of a film analysis about what makes it so successful and engaging). You can watch the Up Series on YouTube.
You can view the transcript for “Some Kind of Connection- the Up Series” here (opens in new window).
Late Adulthood
Late adulthood is sometimes subdivided into two categories: The young-old who are from 65-84 years and the oldest-old who are 85 years and older. One of the primary differences between these groups is that the young-old are still relatively healthy, productive, active, and the majority continue to live independently. With both age groups the risks of diseases such as arteriosclerosis, cancer, and cerebral vascular disease increase substantially.
Death and Dying
The study of death and dying is seldom given the amount of coverage it deserves. Of course, there is a certain discomfort in thinking about death, but there is also a certain confidence and acceptance that can come from studying death and dying. Factors such as age, religion, and culture play important roles in attitudes and approaches to death and dying. The most common causes of death vary with age, gender, race, culture, and time in history. Dying and grieving are processes and may share certain stages of reactions to loss.
Try It
Think It Over
Think about your own development. Which period or stage of development are you in right now? Are you dealing with similar issues and experiencing comparable physical, cognitive, and psychosocial development as described above? If not, why not? Are important aspects of development missing and if so, are they common for most of your cohort or unique to you?
Licenses & Attributions (Click to expand)
CC Licensed Content
- “Lifespan Development: A Psychological Perspective, Second Edition” by Martha Lally and Suzanne Valentine-French is licensed under a CC-BY-NC-SA-3.0
- “What is Development?” by Ellen Skinner, Glen Richardson, Jennifer Pitzer, and Cynthia Taylor, Portland State University is licensed under a CC BY-NC-SA 4.0.
- Psyc 200 Lifespan Psychology. Authored by: Laura Overstreet. Located at: http://opencourselibrary.org/econ-201/. License: CC BY: Attribution
- “Periods of Human Development” by Lumen Learning. License: CC BY: Attribution
Media Attributions
- Embryo at 8 weeks. Located at: https://commons.wikimedia.org/wiki/File:Human_Embryo_-_Approximately_8_weeks_estimated_gestational_age.jpg. License: CC BY: Attribution
- brothers. Authored by: sathyatripodi. Provided by: Pixabay. Located at: https://pixabay.com/photos/brothers-family-siblings-boys-love-457237/. License: CC0: No Rights Reserved
- Girl in grass. Provided by: pxhere. Located at: https://pxhere.com/el/photo/815322. License: CC0: No Rights Reserved
- teenagers. Provided by: Pxhere. Located at: https://pxhere.com/en/photo/913153. License: CC0: No Rights Reserved
- Coworkers. Authored by: WOCinTech. Provided by: Flickr. Located at: https://www.flickr.com/photos/wocintechchat/25926634151/. License: CC BY: Attribution
- Big kid brothers. Provided by: Pxhere. Located at: https://pxhere.com/en/photo/1563851. License: CC0: No Rights Reserved
- Older man at bar. Provided by: Pxhere. Located at: https://pxhere.com/en/photo/1452979. License: CC0: No Rights Reserved
- Elderly man. Provided by: Pxhere. Located at: https://pxhere.com/en/photo/35917. License: CC0: No Rights Reserved
All Rights Reserved Content
- Some Kind of Connection- the Up Series. Provided by: The Royal Ocean Film Society. Located at: https://www.youtube.com/watch?v=VVQ96wfbf_0. License: Other. License Terms: Standard YouTube License
References (Click to expand)
Guinness World Records. (2016). Oldest person (ever). Retrieved from http://www.guinnessworldrecords.com/search?term=oldest+person+%28ever%29
Neugarten, B. L. (1979). Policy for the 1980s: Age or need entitlement? In J. P. Hubbard (Ed.), Aging: Agenda for the eighties, a national journal issues book (pp. 48-52). Washington, DC: Government Research Corporation.
Neugarten, D. A. (Ed.) (1996). The meanings of age. Chicago, IL: The University of Chicago Press.
Smithsonian National Zoo. (2016). Retrieved from http://nationalzoo.si.edu/
Vogt, W.P., & Johnson, R.B. (2016). The SAGE dictionary of statistics and methodology. Los Angeles, CA: Sage