Developmental disability

Developmental disability is a diverse group of chronic conditions, comprising mental or physical impairments that arise before adulthood. Developmental disabilities cause individuals living with them many difficulties in certain areas of life, especially in "language, mobility, learning, self-help, and independent living".^[1] Developmental disabilities can be detected early on and persist throughout an individual's lifespan. Developmental disability that affects all areas of a child's development is sometimes referred to as global developmental delay.^[2]

The most common developmental disabilities are:

• Motor disorders, and learning difficulties such as dyslexia, Tourette's syndrome, dyspraxia, dysgraphia, dyscalculia, and nonverbal learning disorder.
• Autism spectrum disorder (ASD, formerly the PDD umbrella covering Asperger syndrome and classic autism) causes difficulties in social communication as well as repetitive behaviors and restrictive interests. ASD affects speech, understanding body language and social interactions, as well as causing difficulty in understanding others social cues (such as sarcasm and feelings). ASD also causes repetitive behaviors known as stimming, often as a result of hyper- or hypo-sensitivity to sensory input.
• Down syndrome is a genetic condition in which people are born with an extra copy of chromosome 21. This extra copy affects the development of the body and brain, causing a range of physical and mental impairments for the individual.
• Fragile X syndrome, most frequent among males, is thought to cause autism and intellectual disability.
• Fetal alcohol spectrum disorders are a group of conditions caused prior to birth that can occur in a person whose mother drank alcohol during pregnancy.
• Cerebral palsy is a group of disorders that affect a person's ability to move and maintain balance and posture. They are the most common motor disability in childhood.^[1]
• Intellectual disability or mental retardation, is defined as assessed to have an IQ below 70, along with limitations in adaptive functioning and onset before the age of 18 years.^[3]
• Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by executive dysfunction. It has effects on attention span, cognition, self-control, and emotional regulation.