Melanin has many biological functions, including colouring the skin and hairs or feathers, strengthening plant cell walls and insect cuticle, absorbing light (and so providing photoreceptor shieldlng, thermoregulation, photoprotectlon), and it is an important free radical sink.
Medical Definition of autistic disorder. : autism Autistic disorder is classic autism, one of the more severe disorders on the spectrum. Persons with autistic disorder have substantial impairment in social skills, verbal communication, and cognitive and behavioral flexibility.âIsabelle Rapin , The New England Journal of Medicine, 1 Aug. 2002.
Autistic disorder, sometimes called autism or classical ASD, is the most severe form of ASD, while other conditions along the spectrum include a milder form known as Asperger syndrome, and childhood disintegrative disorder and pervasive developmental disorder not otherwise specified (usually referred to as PDD-NOS).n some cases, parents and other relatives of a child with ASD show mild impairments in social and communicative skills or engage in repetitive behaviors. Evidence also suggests that some emotional disorders, such as bipolar disorder, occur more frequently than average in the families of people with ASD.