How people grow and change across the entire lifespan is a fascinating field of psychology. It can answer the questions about why we develop into who we are and why we change as time goes on.
What is Developmental Psychology?
As you can imagine, this field has a very wide scope. This scope includes understanding how genetic, environmental, and cultural factors influence development.
Researchers in this field study a wide range of topics, like language acquisition, motor skills, identity formation, moral reasoning, and ageing.
By examining these areas, developmental psychologists aim to understand the complex interplay between biological, cognitive, and emotional processes that shape human development.
As this field is so broad, developmental psychologists can come from different backgrounds.
It can be of interest to those pursuing a graduate diploma of psychology advanced, looking to answer specific questions about the cognitive ageing process, as much as it can be fascinating for teachers who want a better understanding of childhood development.
Stages of Development in Developmental Psychology
Splitting these areas of research into more manageable sections makes it easier for researchers to hone in on one specific time in development.
It also allows us to conceptualize different stages in development and see what is, or should be, happening at each stage.
Different theorists have proposed different stages–Jean Piaget created a four-stage model, whereas Erik Erikson created an eight-stage model, but more on that later.
1. Infancy and Early Childhood (0 to 6)
This is where it all begins and is when we develop some key life skills. Infants learn how to trust caregivers, develop attachments, and figure out how to start socialising. Early childhood is a time of rapid development, both physically and cognitively.
2. Middle Childhood (6 to 12)
Between these ages, a lot happens. Kids begin to develop a sense of self-esteem. They learn how to navigate increasingly complex social situations through play, observation and, of course, trial and error. They begin to understand their own identity.
3. Adolescence (12 to 18)
During their teenage years, kids develop a stronger sense of individual identity, seek independence, and form deeper relationships outside the family. As most of us know, teenagers are more likely to take risks and try new things. At the same time, this stage is critical for developing abstract thinking and moral reasoning.
4. Adulthood (18+)
Congratulations. You have made it all the way. But adulthood is a long period with its own complexities.
Sometimes, they are further split into early, middle, and late adulthood. Early adulthood focuses on intimacy and building relationships, while career establishment may be the concentration.
Middle adulthood is maintained through relationships and by giving back to society; life transitions are managed. Reflection about one’s life, physical changes, and finding meaning in life experiences happens in late adulthood.
Theories of Development and Their Theorisers
1. Piaget
Jean Piaget was a child prodigy and genius, publishing his first scientific paper at age 10.
His first academic interests were biological, but he quickly shifted towards psychology. Piaget wanted to understand how we acquire knowledge, eventually naming his theory ‘genetic epistemology’.
As I mentioned, Piaget split his developmental stages into four: Sensorimotor (0-2 years), Preoperational (2-7 years), Concrete Operational (7-11 years), and Formal Operational (12 years and up).
Piaget used these stages to predict where a child ‘should’ be developmentally and designed experiments to test cognitive ability at different stages.
For Piaget, however, the focus was not on intelligence as we might conceptualise it but on how children acquire knowledge and understanding from the world around them. This acquisition can occur while playing with other kids in a sandpit, in the classroom, or by observing new phenomena.
Piaget coined the term ‘Schema,’ which is a cognitive framework or concept that helps individuals organise and interpret information. It allows people to categorise and make sense of new experiences by relating them to existing knowledge.
For example, a child might have a schema for dogs that includes four legs, fur, and barking. When they encounter a new animal that fits this schema, they can quickly identify it as a dog. Unless, of course, this new animal is actually a wolf, they must create a new schema for ‘wolf.’
2. Vygotsky
Lev Vygotsky was a Russian psychologist whose work put a heavy emphasis on how social systems and social interactions shaped development–especially in children and young people.
Vygotsky’s Theory of Cognitive Development strongly emphasises the role of social interaction and cultural context in development.
One of Vygotsky’s concepts you may have heard of is the Zone of Proximal Development; that is, the difference between what a child can do independently and what a child can’t but is able to do with the assistance provided by others.
According to Vygotsky, learning happens best within this zone when there is a strong scaffolding from more informed people like parents and caregivers.
Vygotsky also theorised that mental instruments, like language and symbols, played a vital role in the process of reasoning. According to Vygotsky, language forms the base of cognitive development: it merges with thinking to allow complex reasoning.
3. Erikson
Erik Erikson took a slightly different approach, theorising that human development unfolds across eight stages, each with its unique ‘identity crisis’.
The stages range from learning to trust others as babies to working out identity during teenage years and going on until old age.
Erikson made an important shift in emphasis from biological influences to one emphasising social relationships and experiences as influential upon our development.
Meeting these challenges at each stage will help us in developing a healthy sense of self and well-being. Erikson’s ideas about psychosocial development continue to influence our understanding of how we develop across life.
The Importance of Development Psychology
These theories are massively simplified versions of the culmination of great men’s life work. They have impacted how we teach children, how we parent, how we deal with ageing, and how we address challenges like cognitive decline.
Piaget’s theories alone have set useful benchmarks for cognitive development and helped normalise and address developmental challenges.
Some of the most groundbreaking studies are in the field of development. Several of the American Psychological Association’s (APA) most downloaded studies to date relate to questions like what the COVID-19 pandemic did to young people’s social development.
Longitudinal studies like the Dunedin study, which has been going on for 50 years, have published hundreds of papers on key developmental questions, like whether some people are naturally more aggressive.
If you want to find answers to these questions, development is the place to look, and the opportunities are nearly endless.