Everyone grows and changes throughout their life, but why do some people have developmental problems? In this lesson, we'll look at common lifespan development disorders and major theories about how people develop them.
Imagine that you are only a year old sitting on the floor next to a chair. From your vantage point, you can't see the seat of the chair because it's above your head. You reach up and put your hands on the edge of the chair. With all the strength in your legs and arms, you pull yourself up to stare over the edge of the seat and look at the top of the chair. Now imagine that you're an adult, sitting in that same place in front of the chair. But, you're bigger now, and you can see the seat of the chair from your sitting position. And, if you want to stand up, you'll probably look very different from that little kid standing up.
Human development is the study of how people change throughout their lives. The way we perceive our environment, like whether you can see the seat of a chair while sitting on the floor, is only one way that humans develop. Other developments include intellectual, emotional, and behavioral development. Let's look closer at how people develop and some lifespan development disorders.
Lifespan Development Disorders
There are general ways that most people develop: children crawl and then walk, students learn to add and then multiply, and people throw temper tantrums and then negotiate. But, not everyone develops at the same rate. Some variability in the way that people develop is normal. For example, some children read at age five, others at age eight.
But, what happens when development, or lack thereof, causes problems in a person's life? Lifespan development disorders are psychological disorders that are characterized by abnormal development. Usually, this means severe developmental delays. There are several major lifespan development disorders:
- Autism and Asperger's Syndrome - People with autism and Asperger's syndrome have emotional and behavioral developmental delays. They have problems communicating and interacting with others. They have very rigid behavioral patterns and don't like it when their schedule is interrupted.
- Attention Deficit Hyperactivity Disorder - ADHD patients have attentional and behavioral developmental issues. They are easily distracted or have trouble paying attention. They are also hyperactive and have trouble controlling their behaviors.
- Conduct Disorder - Patients with conduct disorder, and the related oppositional defiant disorder, have behavioral developmental delays that mean they act like they never outgrew the 'terrible twos.' They are rude and act in ways that show very little respect for others. Conduct disorder patients consistently break rules and disregard other people's rights.
- Learning Disabilities - Some students have issues with reading, writing, and math. These learning disabilities, like dyslexia, dysgraphia, and dyscalculia, prevent people from developing academically.
- Intellectual Disability - Patients with intellectual disability (formerly known as mental retardation) have a significantly low IQ. In other words, they do not develop intellectually.
As we mentioned before, there are natural variances in development. Some people develop at quicker rates than others, and some develop more slowly. As a result, most of the lifespan development disorders are on a spectrum. That is, people show signs of the disorders to varying degrees, and even people who do not have severe enough symptoms to be diagnosed with a disorder may still show symptoms of the disorder.
Major Views of Development
So, if lifespan development disorders are caused by abnormal development, what constitutes normal development? Sarah is only eight years old, but she is able to see both sides of every argument. Even if she disagrees with someone, she understands where they are coming from. On the other hand, Sarah's sister Lynn is eleven and still doesn't understand that other people might have a valid argument. To Lynn, her side is the right side; if it wasn't the right side, she'd switch sides! What could cause the differences in the sisters? How do people develop?
Throughout the course of history, many different psychologists have tried to answer that question. As a result, there are many different theories of development. Freud's psychoanalytic theory of development says that people learn and grow by dealing with or suppressing urges and thoughts. They might believe that Lynn is unable to see another side because she's still stuck in an early stage of development where her ideas are rigidly defined.
On the other hand, social learning theory says that people develop through their relationships with others and the world at large. Social learning theorists might see Sarah as advanced because she has encountered many people different from her, which taught her that a different viewpoint isn't always bad.
The information processing theory of development says that people grow in their ability to perceive and understand the world around them. In this way, perhaps Sarah is advanced because she's able to process more pieces of information, while Lynn is left with a more simplistic view of the world.
Finally, the evolutionary theory of development says that people grow in order to survive and thrive in the world. Maybe Sarah's first grade teacher held a very different view of life than Sarah did. In order to pass the class, Sarah had to see and give credit to her teacher's opinion. As a result, Sarah learned to understand both sides.
At different points in history, each of these theories has been popular. For example, the psychoanalytic theory was the predominant one at the end of the 19th century, whereas social learning theory was popular in the middle of the 20th century. Today, however, most psychologists recognize that different theories have their merits and that a combination of more than one theory can often explain how people develop.
In the late 20th century, a new view of development began to emerge. Before, the term 'development' was only used to describe how children become adults. Once adulthood was reached, it was widely believed that development was over.
But in the last fifty years, psychologists have begun to recognize that people continue to grow and learn throughout their lives. And as people live longer and longer, issues relating to old age have emerged. Dementia, delirium, and other psychological problems associated with old age are becoming more and more common.
As a result of the awareness that people develop throughout adulthood and awareness of the psychological disorders related to aging, the concept of development has been widened from merely how to go from birth to adulthood to how to go from birth to death. The term 'lifespan development' has become a more common and accurate way of looking at how people grow.
Human development is the study of how people change and grow throughout their lives. When a person does not develop normally, they are often diagnosed with one of the lifespan development disorders, including autism, ADHD, conduct disorder, learning disabilities, and intellectual disability. There are many theories to explain how people develop, though the current predominant theory is that there are many factors affecting growth. Finally, development used to be used only to explain the period from birth to adulthood, but more recently it has looked at the entire lifespan from birth to death.
At the end of this lesson, you'll be able to:
- List and describe the characteristics of several developmental disorders
- Describe different psychological theories of development
- Summarize how psychologists are now looking at old age in the lifespan development process