Developmental disorder

Developmental disorders are a group of psychiatric conditions that begin during childhood. These conditions involve serious impairments in several different areas of life. These areas can include social skills, communication, physical movement, and intellectual abilities. Some experts use a narrow definition for these conditions. The ICD-10 uses the term "Specific Disorders of Psychological Development" for certain types. This category includes developmental language disorder, learning disorders, and autism spectrum disorders (ASD). In a broader sense, the term neurodevelopmental disorders is used. This broader group includes attention deficit hyperactivity disorder (ADHD) as well. Some definitions even include antisocial behavior or schizophrenia that starts in childhood. However, those two conditions are not as stable as other developmental disorders. They also do not show the same evidence of a shared genetic liability.

These disorders are present from early life onward. Most children see improvements as they grow older. However, some impairments continue throughout a person's entire life. It is important to distinguish these from Pervasive Developmental Disorders (PPD). PPD describes a specific group of five different diagnoses. One of those diagnoses is autism spectrum disorder (ASD). In contrast, developmental disorders represent a much larger network. This network covers many concerns, including genetic, behavioral, and language issues. Learning disabilities are often diagnosed when children first begin school. Most of these are found before a child reaches age 9. Communication disorders can also appear very early. Some children may not speak at all or have a very small vocabulary. As they grow, they may struggle to understand directions or name objects. Older children often have trouble forming words, while teens may struggle with abstract ideas.

Scientists study many different theories to find the causes of these disorders. They look at how the environment and genetics work together. Normal development is a combination of both factors. One theory suggests that environmental disruption causes these issues. Researcher Bruce D. Perry suggests that early childhood traumatization is a factor. He compares these developmental difficulties to adult post-traumatic stress disorder. Other theories suggest that even small stresses can add up over time. These stresses can lead to social or emotional disorders. Genetics also play a major role in development. A 2017 study in the UK and Ireland examined 4,300 families. Researchers tested 20,000 genes to find causes for rare difficulties. They discovered 14 new disorders caused by spontaneous genetic mutations. These mutations are not found in either parent. It is estimated that one in 300 children is born with such mutations.

Autism spectrum disorder (ASD) is a specific type of neurodevelopmental disorder. The first case of ASD was published in 1943 by Leo Kanner. He was an American psychiatrist. ASD is difficult to detect because it has a wide range of severity. A diagnosis can be made accurately before a child turns 3 years old. However, confirmation often happens later. In the USA, the mean age for diagnosis is 4 years old. The age of diagnosis can range from 9 months to 14 years. On average, a case is tested at three different centers before it is confirmed. Early diagnosis is very helpful for families. It can speed up access to special educational programs and reduce family stress. Additionally, the occurrence of ASD in one child increases the risk for the next child. This risk can be 50 to 100 times higher.

In ASD, the brain is wired in a different way. This involves structural changes in several important areas. The cortex is one area that shows changes. The cortex controls memory, sensation, and muscle movements. Structural defects are also seen in the cerebellum. This part of the brain affects motor and communication skills. The distribution of white matter is also often abnormal. White matter consists of the nerve fibers that link different brain parts. The corpus callosum is a specific band of fibers that connects the two hemispheres. In some people, this band is partially or completely absent. This condition is known as agenesis of the corpus callosum (AgCC). Research shows that 33% of people with AgCC score above the autism screening cut-off. An ASD child's brain also grows very rapidly. It is almost fully grown by the age of 10.

Symptoms of ASD vary greatly between individuals. They are often grouped into two main categories. The first category involves persistent issues with social interaction and communication. This includes avoiding eye contact or having difficulty interpreting body language. It also includes being unresponsive in conversations or struggling to maintain relationships. The second category involves repetitive behavioral patterns. This can include repeated hand movements or using the same phrases. Many people with ASD also show a rigid adherence to schedules. They may find it hard to adapt to minor changes in a routine. Sensory patterns are also common. Some individuals have an extreme aversion to certain odors. Others may show indifference to pain or temperature changes.

There are several ways to help people manage these symptoms. There is no single specific treatment for autism. However, many types of therapy are effective. Applied Behavior Analysis (ABA) is considered very effective by the American Academy of Pediatrics. ABA focuses on teaching adaptive skills like social or play skills. It uses reinforcement to encourage positive behaviors. Occupational therapy helps with everyday tasks like personal hygiene. This therapy helps people adapt their environments to their specific skill levels. Speech-language therapy helps improve communication mechanics and social use of speech. For those with low-functioning autism, therapists may help develop basic speech patterns. Finally, sensory integration therapy helps people adapt to stimuli like bright lights or loud sounds. This often involves play with swings or trampolines to engage the senses.

Attention deficit hyperactivity disorder (ADHD) is another neurodevelopmental disorder. It occurs in early childhood and affects 8% to 11% of school-aged children. ADHD is characterized by hyperactivity, inattentiveness, and impulsiveness. There are three distinct subtypes of this disorder. The first is predominantly inattentive. The second is predominantly hyperactive. The third is the combined subtype, which shows both traits. ADHD is twice as common in boys as it is in girls. However, the hyperactive type is more common in boys. The inattentive type affects both sexes equally. Symptoms can lead to academic problems and disruptive behavior. Many children also struggle with social relationships and interpersonal connections. They may also experience mood swings, sleep disturbances, or aggressiveness.