Hello. We are the Association for Child and Adolescent Mental Health or ACAMH for short. I'm Uta Frith. I'm emeritus professor of cognitive development at University College, London. And I have done research in autism since my PhD years, which were 1966 to 1968. Everyone knows the Sally Anne test. It was designed together with Simon Baron-Cohen, who was my PhD student at the time and carried out the experiment, and with Alan Leslie, who was a theoretician of development and who brought a particular insight into this triangle. And that was his idea that pretense, pretend play is a critical very first appearance of theory of mind. So you can see the link to the lack of symbolic pretend play as in Wing and Gould's study and the idea that perhaps that is leading in the case of autism to certain communication difficulties and maybe not understanding that people have beliefs, or false beliefs, true beliefs, or even desires, or other mental states. So attributing mental states, how can we test this? Simon Baron-Cohen did the experiment, which is now known as the Sally Anne experiment. It's too well known, but here are the dolls. I think this one is Sally, and this one is naughty Anne. And of course, Sally has her basket and puts a marble in there. Naughty Anne takes it out and puts the marble into her own box. Child watches all this. Sally goes out. Sally doesn't watch this, and when Sally comes back, the question is where would Sally look for her marble. And of course, Sally must look in the basket where she put the marble because she wasn't there. So she doesn't know that the marble is no longer in her basket. She has a false belief. She believes the marble's in the basket. So children aged 5 or so immediately know this, immediately get this. But younger children actually don't, and that's very, very interesting why they don't and what is different and what it actually means. But this was only one of several experiments with autistic children. There was this other one, the Smarties experiment, where again the question is what you think is in this. Of course, you'd say Smarties. And then surprise, it's a horrible pencil. That's very disappointing. Anyway, that's what's in the box. The question is, if I call the next child in, what will that child say in the box. You ask this question. What will Billy say? Now, autistic children tended to say pencil because that's what's really in the box. And they knew it. And that's reality. But they didn't take into account that Billy who has never been in this room before has never seen this must believe that it's Smarties in the box. So the correct answer, of course, is Smarties and not pencil. So it's the reality. So this interesting idea that perhaps autistic children can orient to the physical world very well and are dominated by that, but the mental world of beliefs and desires and so on is a bit of a closed book to them. They do not attribute to the states. And so much of the work with Alan Leslie in particular was trying to trace consequences of this, what would it explain about autism if that was the case, which we believed it was that they had this essential problem in interpreting mental states to others. And we thought that it really does explain a lot about their particular difficulties in social relationships, which are actually much more subtle than people often assume. So these children are not totally oblivious, totally asocial. This is one of the things that I also learned quite slowly. But it's that they cannot quite anticipate in a communication what it is that you know and what they need to tell you and what it is that you want them to know and what's really important, what's really relevant in a particular situation. So it seemed-- for example, it explained to us children who would always say the same thing in a way that people would say, well, that's just boring. Well, that's much worse than boring is actually they don't seem to take into account that you've heard it before, you know it. It's not something they should tell you. They should tell you only the thing that you don't know. It would explain why we had all these reports about autistic children who maybe had pain, some accidents, some falling, and they would not tell about it. They would not tell their parents or their teachers what actually happened. That was a big puzzle why they wouldn't do that. But again, it seemed as if they assumed-- I mean, that was our interpretation. Not consciously, of course, that they assume that what they knew, everybody else knew. Now, if you are in that situation, communication is unnecessary. Communication has to do with transmitting things that you don't know. To be part of the advancement of child and adolescent mental health, visit www.acamh.org.