What Is Developmental Psychology?

Developmental psychology can focus on how and why people might grow and change physically, emotionally, and intellectually throughout their lives. Those that work in this field, primarily developmental psychologists, may treat mental health conditions connected to certain life events during a specific life stage. In some cases, they work on research or teaching. Those looking to work in the field of developmental psychology may need to pursue a Ph. D., university degree, or other certification.

What is developmental psychology?

The American Psychological Association defines developmental psychology as “the branch of psychology that studies the changes—physical, mental, and behavioral—that occur from conception to old age.” This field focuses on investigating the biological, social, cultural, psychological, and environmental factors that affect development throughout a person’s life span. The roots of this field were established long before it became a formal discipline, all the way back in medieval times. 

Children weren't often seen as complete people in medieval times and during the reformation period. Some individuals may have believed that children were born evil and that harsh punishment was needed to teach a child how to be an adult. 

During the enlightenment period, Jean-Jacques Rousseau and John Locke had different ideas about children. Locke believed that children were born blank slates and that knowledge was acquired through life experience and adult guidance. Rousseau believed that children were born pure and morally sound. He described children as "noble savages" and stated that they could be born good but taught unhealthy behaviors over time. 

Many other psychologists developed theories of childhood development. One of the later influences on this area of study was Sigmund Freud. Sigmund Freud is known for his theory of human personality, specifically that it is comprised of the ego, superego, and id psychology. Many of Freud's theories about psychological development and the human mind have been debunked. However, his first theories on childhood development may have paved the way for others. 

Freud's psychosexual theory

Freud developed his psychosexual theory in the early 1900s to explain five "erogenous zones" on which children focus throughout development. He claimed that if there were difficulties during development, children would form an innate fixation, which may look like anxiety or another mental health issue. 

Oral

The oral stage was labeled from birth to 12 months. Babies put many objects in their mouth, may suckle from their parents or a bottle, and may start to grow teeth. 

Anal

From one to three years, potty training occurs. A child may become fascinated with their digestive system overall. 

Phallic

From three to five years, the child may become aware of their reproductive system for the first time. 

Latency

From age five to puberty, a child's sexuality may be repressed. 

Genital

From puberty to adulthood, Freud stated that sexuality would return, and teens and adults would explore it in greater detail. Freud's genital stage extended human development into adulthood. However, other theorists expanded developmental psychology to include life stages beyond childhood and into the elderly years. 

The eight life stages according to Erik Erikson

American psychologist Erik Erikson developed an eight-stage model describing each life stage's psychosocial development in the early 1900s. He believed that when the fundamental aspects of a stage were not completed successfully, the following stages may also not be completed successfully, and an individual may develop mental health concerns. In these cases, Erik believed a developmental psychologist could help clients return to past life-stage failures and repair them. 

Birth to 18 months: Trust vs. mistrust

Infants are entirely dependent on their caregivers. During this stage, a baby learns to trust or mistrust the world around them. If caregivers are inconsistent and unreliable, the infant might develop a sense of mistrust and experience anxiety.

18 months to 3 years: Autonomy vs. shame and doubt

The toddler age is when children might develop a will of their own. They could start choosing what they want to wear, eat, and play with. If caregivers encourage a child to make their own choices and give help when asked, the child could become independent and confident. 

On the other hand, if caregivers are critical of the child's choices or don't allow them to be independent, the child might develop low self-esteem. They may feel ashamed and internalize the experience, doubting their abilities. 

3 to 5 years: Initiative vs guilt

Children are often active from three to five years, and they might ask their caregivers and those around them many questions. As children start interacting with others, primarily through play, they may create imaginary games with other children. This creates an environment that can be conducive to social learning and help aid in childhood development.

If children are encouraged to develop these interpersonal skills, they may develop decision-making and leadership skills. On the other hand, children who are criticized for asking too many questions, or are consistently limited in their play with other children may feel that they're a nuisance and develop a sense of guilt.

5 to 12 years: Industry vs. inferiority

In this stage, children may want approval. They could strive to develop skills that others admire and feel a sense of pride in their accomplishments. Children encouraged to show initiative and develop skills might feel diligent and confident. Children subjected to criticism and limitations could feel inferior and hold back on following their dreams as adults. 

12 to 18 years: Identity vs. role confusion

When an adolescent transitions from early childhood to adulthood, it can be challenging and confusing for all involved. Adolescents might question who they are and what influence they want to have in the world. They might also want to fit in with the crowd. Often, they consider careers and first loves. As this happens, teenagers might challenge the values and beliefs of their caregivers.

In addition to the intense exploration of self, the adolescent can deal with significant and uncomfortable body changes. Teenagers who complete this life stage healthily may develop a solid sense of identity. Unsuccessful teenagers may be confused, unsure, and unhappy. They may experiment with different lifestyles and unhealthy behaviors. 

18 to 40 years: Intimacy vs. isolation

The 18 to 40 stage is often about developing intimate and loving relationships. Persons belonging to young adulthood may search for a life partner or a long-term commitment from another person. In some cases, they may want to settle down or complete a family. 

The completion of this stage is a happy relationship where the young adult feels safe and loved. Failure to establish a healthy, loving relationship during this life stage may be due to a fear of intimacy and commitment or difficulty in relationships. Isolation, loneliness, and depression might follow, according to psychologists. 

40 to 60 years: Generativity vs. stagnation

From 40 to 60, people may start to think about their legacy. They may want to engage with people who will outlive them. Middle adulthood often focuses on raising children, being productive, and helping others achieve goals. Adults in this stage might focus on giving back to society and making positive changes to benefit others. Success during these middle years may lead to feelings of usefulness and accomplishment. Failure could lead to stagnation or feeling disconnected.

65 to death: Ego integrity vs. despair

The last part of Erikson’s stages of development takes place from age 65 to death; this is often the time when people reflect on their lives. If senior citizens look back on their lives and feel a sense of completeness and wisdom, they may feel content and accept death without fear. However, those who feel guilty about their past or didn't reach their goals might feel dissatisfied and bitter, which could lead to despair. 

Debates on developmental psychology

As the study of developmental psychology expanded in the past, debates developed around conflicting opinions and ideas. Some of the ideas and opinions being debated can be found in peer-reviewed academic journals like Developmental Psychology. This journal focuses on articles and studies that advance knowledge and theories pertaining to human development. Due to the manuscript acceptance rules that Developmental Psychology and other academic journals utilize, the information within them may be considered more trustworthy than non-academic sources.

In addition to what can be found in modern journals, debates about developmental psychology can be found throughout history. Some of these debates include:  

Nature vs. nurture

Nature vs. nurture is an ancient philosophical debate. Plato and Descartes believed that we are born with some knowledge, while John Locke believed that people are born a blank slate and gain understanding through experience. Modern psychologists may believe that development is focused on both nature and nurture and that both have an influence. 

Early experience vs. later experience

Freud believed a child's personality was complete and unchangeable by age five. This theory meant that healthy psychological and emotional development would be beyond the reach of those who have experienced childhood trauma. However, current empirical research shows that adults can change their attachment styles, make positive life changes, and develop even after childhood. Additionally, the brain is still developing until age 25. This and other findings are what led to the debunking of much of Freud’s published work. 

If you are experiencing trauma, support is available. Please see our Get Help Now page for more resources.

Abnormal behavior vs. individual differences

Caregivers might feel nervous when a child doesn't meet developmental milestones. Researchers debate whether a child should be labeled abnormal if the milestones aren't met or if their differences are just differences. 

Each child can be unique, and their environment may play a role in their development. For example, research findings have shown that children from dysfunctional families may not meet developmental milestones, and may experience behavioral problems. Child development milestones and environmental issues may be considered simultaneously in modern psychology before creating a treatment plan. 

How do developmental issues form?

Negative developmental outcomes may lead to mental health conditions, such as anxiety or depression. These problems may occur if: 

• Life stages have not been completed
• Adolescents struggle with the challenges and difficulties unique to the teenage years
• People are unable to form healthy relationships and overcome problems relating to emotional growth
• People feel isolated and lonely
• People feel unable to face the challenges of aging

Developmental psychologists study these problems extensively and may be able to help individuals overcome them. They might use screening tools to determine when the problem started in one's life. Depending on the results, the therapist could choose one theory or a combination of development theories to treat symptoms.

Other developmental theories 

There are many developmental theories, including the following: 

• Piaget's Theory Of Cognitive Development: Piaget believed children learn by experimenting and observing.
• Bowlby's Theory Of Attachment: Bowlby's theory focuses on the long-term attachments children form with their caregivers. 
• Vygotsky's Theory Of Sociocultural Development: Vygotsky's theory is newer than others and looks at the interaction between people and their cultures. Vygotsky suggests that human development is a social process.

How to find a counselor 

Developmental psychology may be continually expanding and adapting new theories. Psychologists might continue to explore prenatal development, adult attachment, and how mental health conditions develop over time. The more we gain a complete understanding of developmental psychology and how it relates to us, the more we may fulfill our potential, form healthy relationships, and live happy lives into our old age.

If you're experiencing distressing symptoms or have been diagnosed with a mental health condition related to the developmental stages, you might benefit from speaking to a psychologist about your experiences. You can look for a therapist in your area or try a modern form of therapy, such as online counseling. 

Online therapy is often more convenient and less expensive than traditional therapy. Additionally, it is as effective as in-person therapy in many circumstances. If you're interested in trying this treatment modality, consider reaching out to a counselor on a platform like BetterHelp for individuals or Regain for couples.