Autism is a brain development disorder that causes difficulties in communication, social interaction and verbal responses. The autism spectrum disorder describes a range of behaviors for those who are afflicted with the condition, and terms include Asperger syndrome, Rett syndrome, pervasive development disorder-not otherwise specified, and childhood disintegrative disorder.

Like its many names, the condition has a range of symptoms, including intellectual development issues, attention problems, physical coordination difficulties, gastrointestinal disorders and sleep problems. Yet some autistic people have above-average levels of intelligence in math, music and art, and many who are diagnosed with the disorder go on to conduct normal work and social lives.

To date, there is no one definitive cause of autism that has been discovered, although its first signs usually will manifest between 12 months and 18 months of age. But some children get beyond age two and then suddenly start to lose their communication and motor skills, a problem called regression.

The Centers for Disease Control and Prevention believe that one in 68 American children falls somewhere on the autism spectrum, and the problems appear to be increasing. More boys than girls acquire autism, and the differences are stark – one in 42 boys is diagnosed, while just one in 189 girls is placed on the spectrum. It’s a problem for more than 2 million American individuals, and tens of millions internationally.

While some would argue that better diagnosis is responsible for the growth in cases reported, many autism experts disagree, and many blame environmental and genetic issues for its development.