As we explore development across the lifespan, we will divide the lifespan into discrete stages or periods of development. Each of these stages is associated with a range of ages and we can describe what is expected during each of them. This general understanding of each stage of life is what makes this course valuable and, at times, a little overwhelming. In order to make it manageable, we'll strive to make connections between life stages and across theories. In addition, important concepts and terminology will be emphasized to assist you in learning them. In addition to exploring basic development theories and the research methods that are employed to develop our understanding, we will progress through the following periods of development:
Conception and Prenatal Development
Infancy
Early Childhood
Middle Childhood
Adolescence
Emerging/Early Adulthood
Middle Adulthood
Late Adulthood
Death and Dying
As we consider each stage of life, we'll consider physical, cognitive, and psychosocial development. So, while both an 5-year-old and a 10-year-old are considered children, they have very different 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, both considered adults. We will discover the distinctions between being 28 or 48 as well. But first, here is a brief overview of the stages.
Figure 1.5.1: Two smiling girls. (License; Author via Source)
Prenatal Development
The developmental journey begins at conception, when egg and sperm combine to form a zygote. All of the major structures of the body are forming and the health of the pregnant person is of primary concern. Understanding nutrition, teratogens (environmental factors that can interfere with development), and labor and delivery are primary concerns. We'll explore the role of genes and chromosomes, the importance of the prenatal environment, and the various prenatal stages as we consider the processes that result in a new life entering the world.
Figure 1.5.2: At the embryo stage the head is large and arms and legs are visible. (CC BY; lunar caustic via Flickr)
Infancy and Toddlerhood
The first few 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
Early childhood is also referred to as the preschool years consisting of the years which follow toddlerhood and precede formal schooling. As a 3-5-year-olds, the child is busy learning language, gaining a sense of self and greater independence, and beginning to learn the workings of the physical world. This knowledge does not come quickly, however, and preschoolers may initially have interesting conceptions of size, time, space, and distance - such as fearing that they may go down the drain if they sit at the front of the bathtub or by demonstrating how long something will take by holding out their two index fingers several inches apart. A toddler’s fierce determination to do something may give way to a four-year-old’s sense of guilt for doing something that brings the disapproval of others.
Middle Childhood
The ages of about 6-11 comprise middle 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 by assessing one’s abilities and accomplishments by making comparisons between self and others. Schools compare students and make these comparisons public through team sports, test scores, and other forms of recognition and children begin to learn about social relationships beyond the family through interaction with friends and other students.
Adolescence is a period that begins with the physical changes associated with puberty and ends with the transition to adulthood (approximately ages 10–18ish). It is a period of dramatic physical change marked by an overall physical growth spurt and sexual maturation, known as puberty. It is also a time of cognitive and psychological change as the adolescent begins to think of new possibilities and to consider abstract concepts such as love, fear, and freedom. Ironically, adolescents have a sense of invincibility that puts them at greater risk of dying from accidents or contracting sexually transmitted infections that can have lifelong consequences.
Emerging/Early Adulthood
Emerging adulthood is a newer term that has been proposed as a new life stage between adolescence and early adulthood, lasting roughly from ages 18 to 25. Not everyone experiences emerging adulthood though, as this is a cultural phenomenon we will explore. The twenties and thirties are more traditionally thought of as early adulthood. We will be studying the difference between emerging adulthood and early adulthood in this course. It is a time when we are at our physiological peak but are most at risk for involvement in violent crimes and long term substance abuse. It is a time of focusing on the future and putting a lot of energy into making choices for that. Typically, love and work are primary concerns at this stage of life.
Middle Adulthood
The 40's-60's is referred to as middle adulthood. This is a period in which aging, that began earlier, becomes more noticeable and a period at which many people are at their peak of productivity in love and work. It may be a period of gaining expertise in certain fields and being able to understand problems and find solutions with greater efficiency than before. It can also be a time of becoming more realistic about possibilities in life previously considered; of recognizing the difference between what is possible and what is likely.
Late Adulthood
Late adulthood is sometimes subdivided into two or three categories such as the “young old," "middle old," and “oldest old”. We will follow the former categorization and make the distinction between the “young old” who are people between 65 and 79 and the “old old” or those who are 80 and older. One of the primary differences between these groups is that the young old are very similar to midlife adults; still working, still relatively healthy, and still interested in being productive and active. The “old old” remain productive and active and the majority continues to live independently, but risks of the diseases of old age such as arteriosclerosis, cancer, and cerebral vascular disease increases substantially for this age group. Issues of housing, healthcare, and extending active life expectancy are only a few of the topics of concern for this age group. A better way to appreciate the diversity of people in late adulthood is to go beyond chronological age and examine whether a person is experiencing optimal aging (aging with maximum psychological and physical well-being for one's own makeup, which can vary greatly from person to person), normal aging (in which the changes are similar to most of those of the same age), or impaired aging (referring to someone who has more physical and/or psychological challenges and disease than others of the same age).
Death and Dying
This topic 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. We will be examining the physical, psychological, and social aspects of death, exploring grief or bereavement, and addressing ways in which helping professionals work in death and dying. And we will discuss cultural variations in mourning, burial, and grief.
