disorder" was redefined, and supplemented with the new conditions Asperger syndrome, Rett syndrome and childhood disintegrative disorder (CDD). PDD-NOS remained. The definition of Asperger syndrome included speech and language difficulties. American animal behaviourist Temple Grandin came to prominence in 1995, with the publishing of her popular book Thinking in Pictures: My Life with Autism. She would later become a board member of the Autism Society of America. The term "neurodiversity" was coined in 1998 by Australian sociologist Judy Singer and American self-advocate Jane Meyerdin. Neurodiversity is the idea that people can think differently to the norm without those differences being a medical problem. The influential book Asperger’s Syndrome: A guide for parents and professionals was published by British-Australian psychologist Tony Attwood in 1998. Attwood went on to publish widely on autistic topics. A survey of Ontario autism support workers in 2011 found that 52% had support programs influenced by him. Also in 1998, British doctor Andrew Wakefield published a controversial paper claiming a link between some vaccines and autism. It was subsequently found to be fraudulent. 2000–2004 The DSM-IV TR (2000) contained an almost complete rewrite of the definition of Asperger syndrome. Notably, it now no longer included speech and language difficulties. In 2003, British child psychologist Elizabeth Newson at the University of Nottingham published an article in the Archives of Disease in Childhood journal arguing that pathological demand avoidance (PDA) be recognised as a unique profile within the autism spectrum. She had first seen the pattern of PDA in children in 1980. She believed that autistic people with pronounced PDA symptoms tend to behave quite differently to those that don't. Autistic-specialist employment services company Specialisterne was founded by Danish IT worker Thorkil Sonne in 2003. It has gone on to operate in various parts of Europe, North America and Australia. 2005–2009 World Autism Awareness Day was established by the United Nations in 2007. Lighting buildings with blue light at night is a common means of awareness raising on this day. Autism Speaks has embraced it. The character Sheldon Cooper first appeared on American television in 2007, in the popular sitcom The Big Bang Theory. While he is not explicitly autistic, according to the actor who plays him as an adult, the character "couldn't display more traits" of Asperger's syndrome. The concept of the double empathy problem was conceived in 2012 by British psychologist Damian Milton. The idea proposes that