Cognitive profiles of adults with high functioning autism (HFA) and Asperger Syndrome

Transcription

1 Cognitive profiles of adults with high functioning autism (HFA) and Asperger Syndrome Proefschrift ter verkrijging van de graad van Doctor aan de universiteit Leiden, op gezag van de Rector Magnificus Dr. P.F. van der Heijden, volgens besluit van het college voor promoties te verdedigen op donderdag 2 september 2010 te klokke 13:45 door Antoinette Alida Spek geboren te Lexmond in 1975

2 Promotiecommissie Promotoren Prof. Dr. I.A. van Berckelaer-Onnes Prof. Dr. E.M. Scholte Overige leden Prof. Dr. J.T. Swaab-Barneveld Prof. Dr. R.B. Minderaa, Rijksuniversiteit Groningen Prof. Dr. H. Roeyers, Universiteit Gent, België Prof. Dr. J.A. Sergeant, Vrije Universiteit Amsterdam

3 ISBN: Cover afbeelding: Stefan Bleekrode Printed by: Ipskamp Drukkers B.V. Amsterdam, The Netherlands Copyright A.A. Spek All rights reserved. No part of this thesis may be reproduced in any form by print, photo print, microfilm or any other means without the written permission of the author.

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5 CONTENTS 1 Introduction Aims and Structure Cognitive Theories of ASD 4 2 The Use of WAIS-III in HFA and Asperger Syndrome Introduction Aims of the Present Study Methods Procedure Subjects Assessment of Disorder Assessment of Intelligence Results Differences Between WAIS III VIQ and PIQ Differences Between Factor Scale Scores Differences Between WAIS III Subtest Scores Discussion WAIS VIQ Versus PIQ WAIS III Factor Scale Level WAIS III Subtest Level Conclusions 21 3 Theory of Mind in Adults with HFA and Asperger Syndrome Introduction Theory of Mind in Autism Hypotheses of the Present Study Methods Procedure Assessment of Disorder Assessment of Theory of Mind Assessment of Intelligence Matching Procedure Results Differences in the Neuropsychological Tasks Differences in Self-reported Theory of Mind 33

6 3.3.3 The Association Between the Neuropsychological Tasks and Self-reports The Ability of the Tests to Predict Whether a Diagnosis is Present Discussion Limitations 40 4 Detailed Information Processing in Adults with HFA and Asperger Syndrome: The Usefulness of Neuropsychological Tests and Self-reports Introduction Detailed Information Processing in Autism Detailed Information Processing in Adults with ASD Hypotheses of the Present Study Methods Procedure Assessment of Disorder Assessment of Detailed Information Processing Assessment of Processing Speed Matching Procedure Results Differences in EFT Response-time and Block Design Performance AQ Detailed Information Processing and Systemizing Tendencies The Relationship Between the Neuropsychological Tasks and Questionnaires Exploration of the Predictive Validity of the Tasks and Questionnaires The Influence of Processing Speed on Embedded Figures Test Discussion Limitations 58 5 Verbal Fluency in Adults with HFA and Asperger Syndrome Introduction Verbal Fluency and Underlying Mechanisms Aims of the Present Study Methods Procedure Assessment of Disorder Assessment of Intelligence Assessment of Semantic and Phonemic Fluency Analysis of Underlying Mechanisms 66

7 5.2.6 Matching Procedure Results Differences in Verbal Fluency Between the Three Groups Processing Speed in the Three Groups The Relationship Between Verbal Fluency and Processing Speed The Use of Clustering and Switching Discussion Differences in Verbal Fluency Performance The Relationship Between Verbal Fluency and Processing Speed Cluster-size and Switching Conclusions Limitations 74 6 General Discussion and Conclusions Introduction Main findings Intelligence Profiles Theory of Mind Detailed Information Processing Executive Functioning Autistic Disorder versus Asperger Syndrome Clinical Implications Limitations and Implications for Future Research 83 7 Nederlandstalige Samenvatting 87 References 97 Curriculum Vitae 109 Dankwoord 111

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