Final answer:
Childhood Disintegrative Disorder (CDD) is a rare neurodevelopmental disorder that leads to a significant loss of previously acquired skills.
Step-by-step explanation:
Childhood Disintegrative Disorder (CDD), also known as Heller's syndrome, is a rare neurodevelopmental disorder that affects children. It is characterized by a significant loss of previously acquired skills in multiple areas of functioning, including language, social skills, motor skills, and cognitive abilities. The regression usually occurs between the ages of 3 and 4 years, after a period of typical development.
Individuals with Childhood Disintegrative Disorder may lose the ability to speak, lose bladder and bowel control, have difficulty with social interactions, and experience intellectual disability. They may also exhibit repetitive behaviors, such as hand flapping or rocking.
Unlike Autism Spectrum Disorder (ASD), which is a lifelong condition, CDD leads to a severe decline in functioning and can have lasting effects on an individual's life and independence. The exact cause of CDD is unknown, but research suggests that genetic and environmental factors may play a role.