Today s goals. Today s reading. Autistic Spectrum Disorder. INF1-CG 2014 Lecture 27

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1 INF1-CG 2014 Lecture 27 Autistic Spectrum Disorder Richard Shillcock 1 /26 Today s goals Look at Autistic Spectrum Disorder (ASD) and cognition, with particular attention to language and the linguistic savant Christopher. 2/26 Today s reading Bates, E. (1997). On language savants and the structure of the mind: A review of Neil Smith and Ianthi-Maria Tsimpli, The mind of a savant: Language learning and modularity. International Journal of Bilingualism, 1, /26

2 Autism Calendrical skills Counting skills Drawing skills Autism spectrum and Asperger syndrome 4 /26 Physiological changes in ASD agenesis of the superior olive dysgenesis of the facial nucleus reduced numbers of Purkinje neurons hypoplasia of the brainstem and posterior cerebellum increased neuron-packing density of the medial, cortical and central nuclei of the amygdala and the medial septum abnormal brain growth regulation 5 /26 Face processing in ASD Pierce et al. (2001) Blue = normal Autistics have less experience with faces and show reduced, idiosyncratic patterns of activation 6 /26

3 Stephen Wiltshire 7/26 Delayed development ASD and language Gillberg (1998) Superficially perfect expressive language Formal pedantic language Odd prosody, peculiar voice characteristics Impairment of comprehension including misinterpretations of literal/implied meanings 8/26 ASD and social interaction Gaze judgement task Sally-Anne task (see later film) Theory of Mind deficit 9 /26

4 ASD and spatial skills There are similarities between ASD and RH dysfunction, leading to neurophysiological models of ASD. 10 /26 The mind of a savant: Language learning and modularity Neil Smith & Ianthi-Maria Tsimpli (1995) 11/26 The mind of a savant: 12/26

5 The mind of a savant: 13/26 Christopher s spatial skills Tsimpli & Smith Noughts and crosses 14/26 First language: minor deficits How come you goed home so early? How come did you go home so early? Christopher s language skills Problems with jokes, meta-level representations John said that Harry is leaving the next day Second languages: translation skills in languages, but more lexical than syntactic 15/26

6 Theory of Mind Mason, Williams, Kana, Minshew & Just (2008) 16 /26 Theory of Mind Mason, Williams, Kana, Minshew & Just (2008) 17 /26 A RH spill-over effect Mason, Williams, Kana, Minshew & Just (2008) 18 /26

7 ASD and coherence Grinter, Maybery & Badcock (2010) The task is to spot that some proportion of the dots are moving coherently. It is impaired in ASD and other neurodevelopment disorders. 19 /26 ASD and coherence Ronconi, Gori, et al. (2012) A zooming-out attentional deficit is implicated, related to severity of autism. 20 /26 ASD and attentional zooming Ronconi, Gori, et al. (2012) A zooming-out attentional deficit is implicated, related to severity of autism. 21 /26

8 Weak coherence Happé & Frith (2006) ASD individuals can present with acute attention to detail, a preoccupation with parts and not wholes. Normally we need the gist, the meaning of something. Frith (1989) characterized ASD concentration on detail as weak central coherence. This analysis changed to one of a contributory processing bias. 22/26 Weak coherence and Theory of Mind Happé & Frith (2006) ASD has also been discussed in terms of Theory of Mind (ToM) (Baron-Cohen, Leslie & Frith,1985). Computational perspectives have included an overemphasis on conjunctive coding (McClelland, 2000) leading to hyper specificity. Other architectural and parameter-based proposals have been made in the connectionist framework, all leading to poorer generalization. 23/26 Challenges To delineate the advanced skills that autistic savants possess, and discern what is social and what is non-social in their behaviour. To understand non-social, lexically oriented aspects of language as one such skill. To understand what is new and specific at each level of functioning, not reducing phenomena to a language of neuophysiology. To understand the gradedness and heterogeneity of ASD and its relation to processing in the 24 neurotypical range. /26

9 References Pierce, K., Müller, R. A., Ambrose, J., Allen, G., & Courchesne, E. (2001). Face processing occurs outside the fusiformface area in autism: evidence from functional MRI. Brain, 124(10), Gillberg, C. (1998). Asperger syndrome and high-functioning autism. The British Journal of Psychiatry, 172(3), Hugdahl, K., Gundersen, H., Brekke, C., Thomsen, T., Rimol, L. M., Ersland, L., & Niemi, J. (2004). FMRI brain activation in a finnish family with specific language impairment compared with a normal control group. Journal of Speech, Language & Hearing Research, 47(1), Mason, R. A., Williams, D. L., Kana, R. K., Minshew, N., & Just, M. A. (2008). Theory of mind disruption and recruitment of the right hemisphere during narrative comprehension in autism. Neuropsychologia, 46(1), Ronconi, L., Gori, S., Ruffino, M., Franceschini, S., Urbani, B., Molteni, M., & Facoetti, A. (2012). Decreased coherent motion discrimination in autism spectrum disorder: The role of attentional zoom-out deficit. PloS one, 7(11), e Grinter EJ, Maybery MT, Badcock DR (2010) Vision in developmental disorders: Is there a dorsal stream deficit? Brain Res Bull 82(3 4): Happé, F., & Frith, U. (2006). The weak coherence account: detail-focused cognitive style in autism spectrum disorders. Journal of Autism and Developmental Disorders, 36(1), /26 References Frith, U., (1989). Autism: Explaining the Enigma. Blackwell. Baron-Cohen, S., Leslie, A. M., & Frith, U. (1985). Does the autistic child have a theory of mind? Cognition, 21, McClelland, J. L. (2000). The basis of hyperspecificity in autism: A preliminary suggestion based on properties of neural nets. Journal of Autism & Developmental Disorders, 30, /26