Quantifying Narrative Ability in Autism Spectrum Disorder: A Computational Linguistic Analysis of Narrative Coherence

Abstract

Autism is a neurodevelopmental disorder characterized by serious difficulties with the social use of language, along with impaired social functioning and ritualistic/repetitive behaviors (American Psychiatric Association in Diagnostic and statistical manual of mental disorders: DSM-5, 5th edn. American Psychiatric Association, Arlington, 2013). While substantial heterogeneity exists in symptom expression, impairments in language discourse skills, including narrative (or storytelling), are universally observed in autism (Tager-Flusberg et al. in Handbook on autism and pervasive developmental disorders, 3rd edn. Wiley, New York, pp 335–364, 2005). This study applied a computational linguistic tool, Latent Semantic Analysis (LSA), to objectively characterize narrative performance in high-functioning individuals with autism and typically-developing controls, across two different narrative contexts that differ in the interpersonal and cognitive demands placed on the narrator. Results indicated that high-functioning individuals with autism produced narratives comparable in semantic content to those produced by controls when narrating from a picture book, but produced narratives diminished in semantic quality in a more demanding narrative recall task. This pattern is similar to that detected from analyses of hand-coded picture book narratives in prior research, and extends findings to an additional narrative context that proves particularly challenging for individuals with autism. Results are discussed in terms of the utility of LSA as a quantitative, objective, and efficient measure of narrative ability.

Appendix

Frog Prince Story (Opie and Opie 1974)

Once upon a time there was a princess. She went one day to play at the pond. She took her golden ball with her, which was her favorite toy. She played with the ball at the pond, until-oops-the ball fell in the water. She began to cry, and said, “Oh dear, I would give anything to have my lovely ball back again!” Suddenly a frog stuck his head out of the water and said, “Why are you crying?” The princess said, “What use are you, you nasty frog? My ball has fallen into the pond.” The frog said, “I will get your ball for you, if you will be my friend and let me live with you and eat from your plate and sleep on your bed.” “What nonsense,” the princess thought, “He will never be able to get out of the pond, but I will promise what he asks because perhaps he can get my ball back.” So she said to the frog, “If you will get my ball for me I will do all the things you ask.” So the frog dived into the water, picked up the ball with his mouth, and threw it on the ground in front of the princess. When she saw it, she was so happy that she ran off home without thinking of the kind frog. Next day the princess heard a knock just as she was having her dinner. She opened the door and there was the frog! The princess did not like the frog but she remembered her promise. The frog said, “Let me come in and sit near you, and eat your dinner with you.” So the frog ate dinner with the princess. After they had eaten, the frog said, “Carry me upstairs and put me on your bed.” And the princess did what he asked, even though she still thought he was a wet and nasty frog. She secretly hoped that he would be gone when she woke up. But the next morning she was amazed to find that the frog was gone. Instead there was the most handsome prince she had ever seen. He told her that a bad fairy had changed him into a frog until he could find a princess who would be his friend and let him eat with her and sleep on her bed. And the prince and the princess were married and lived happily ever after.

Practical Princess Story (Williams 1978)

Princess Bedelia was as lovely as the moon shining upon a lake full of water lilies. She was as graceful as a cat leaping. And she was also extremely practical. When she was born, three fairies had come to her cradle to give her gifts. The first fairy had given her beauty. The second had given her grace. But the third, who was a wise old creature, had said, “I give her common sense.” “I don’t think much of that gift,” said King Ludwig, raising his eyebrows, “What good is common sense to a princess? All she needs is charm.” Nevertheless, when Bedelia was eighteen, something happened which made the king change his mind. A dragon moved into the neighborhood. He settled in a dark cave on top of a mountain. He sent a message to the king. “I must have a princess to devour,” the message said, “or I shall breathe out my fiery breath and destroy the kingdom.” Sadly, King Ludwig called together his councilors and read them the message. “Perhaps,” said the Prime Minister, “we had better advertise for a knight to slay the dragon. That is what is generally done in these cases.” “I’m afraid we haven’t time,” answered the king. “The dragon has only given us until tomorrow morning. There is no help for it. We shall have to send him the princess.” Princess Bedelia had come to the meeting because, as she said, she liked to mind her own business and this was certainly her business. “Rubbish!” she said, “Dragons can’t tell the difference between princesses and anyone else. Use your common sense. He’s just asking for me because he’s a snob.” “That may be so,” said her father, “but if we don’t send you along, he’ll destroy the kingdom.” Bedelia said, “I see 1’11 have to deal with this myself!” She left the council chamber. She got the largest and gaudiest of her state robes and stuffed it with straw, and tied it together with string. She packed 100 pounds of gunpowder into the center of the bundle. She got a strong young man to carry it up the mountain for her. She stood in front of the dragon’s cave and called. “Come out! Here’s the princess!” The dragon came peering out of the darkness. Seeing the bright robe covered with gold and silver embroidery, and hearing Bedelia’s voice, he opened his mouth wide. When Bedelia gave the signal, the young man heaved the robe down the dragon’s throat. Bedelia threw herself flat on the ground, and the young man ran away. As the gunpowder met the flames inside the dragon, there was a tremendous explosion. Bedelia got up, dusting herself off. “Dragons,” she said, “are not very bright.” She left the young man sweeping up the pieces, and she went back to the castle to have her geography lesson.