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An ongoing debate is whether people with autism spectrum disorder (ASD) have a local processing bias and to what extent impaired contextual processing is associated with this bias. The set of experiments employed in this project examined global and local processing, shifts between global and local processing, and low- and high-level visual processing in an attempt to address this issue. This thesis tested the hypotheses that (1) a local processing bias is associated with impaired global processing in ASD individuals, and (2) atypical processing style is linked with ASD severity. Twenty ASD individuals and 20 IQ and age (15-30 years) matched normal controls were administered a novel embedded figures task (local processing advantageous), a novel form matching task and novel shape integration task (global processing advantageous), a local-global switching task (which assessed attention broadening and attention narrowing ability), and a local and global motion detection task. The Social Responsiveness Scale was used to assess ASD severity. The ASD group correctly detected significantly more embedded shapes than controls. Compared to controls, ASD participants were disproportionately slower on the shape integration task relative to the form perception task. No overall group differences were found in attention broadening or attention narrowing ability. In addition, no group differences were found in local or global motion perception. Results also revealed a significant correlation between ASD severity and (1) faster response time on the embedded figures test, (2) slower response time on the shape integration task, (3) reduced attention broadening ability, and (4) reduced global motion perception. These findings confirm previous reports of enhanced local visual processing in ASD, and suggest that while global form perception is intact in ASD, global integration is more problematic. There was no evidence of generalized attentional impairments or motion perception abnormalities in ASD participants, suggesting that lower-level perceptual functions may be spared in people with ASD. Perhaps most intriguing was the observed association between ASD severity and enhanced local perception and impaired global processing. This association suggests that both a local processing bias and impaired global processing may play a role in the behavioral aspects of ASD symptomatology.

Autism is a behaviourally defined disorder. The impairments in social communication and repetitive behaviours are individually non-specific. The disorder has indistinct boundaries both with other psychiatric disorders and with normal personality types. At the cognitive level, groups of people with autistic disorder can be differentiated from people without the disorder by their ability to reason about beliefs and knowledge (Theory of Mind) and by tests of visual disembedding (central coherence). This study examined whether young people with some of the behavioural features of autism but not necessarily a diagnosis, would show this distinctive cognitive profile. In a sample of 60 young people with additional learning support needs, we found that those with high levels of autistic traits (n=40) showed the same cognitive profile as has been found in people diagnosed with autistic disorder. This supports the view that autism is an extreme on a continuum of cognitive traits. Given the highly heritable nature of autism, we hypothesised that the parents of the young people with autistic traits will also display these cognitive features. The results indicated that there was no difference between the groups of parents on an advanced test of social cognition. Parents of people with high autistic traits were more resistant to one of the visual illusions and saw fewer reversals of an ambiguous figure when IQ was statistically controlled. These results in a sample with a low genetic load suggest ambiguous figures will be important in delineating the broader cognitive phenotype of autism.

The present study examined the relationships between anxiety, cognitive functioning, weak central coherence, and social skills in a group of 102 children diagnosed with an Autism Spectrum Disorder (ASD; Autistic disorder, Asperger's disorder, and PDD-NOS). The results indicated that children diagnosed with Asperger's disorder had significantly higher cognitive functioning and Block Design scores (i.e., weaker central coherence) compared to those diagnosed with autism or PDD-NOS. Regression analyses results showed that anxiety and cognitive functioning moderated the association between weak central coherence and social skills. For children with low cognitive functioning and high anxiety, weak central coherence was associated with poorer social skills than those with low cognitive functioning, high anxiety, and strong central coherence. For children with high cognitive functioning and high anxiety, weak central coherence was associated with better social skills than those with high cognitive functioning and strong central coherence. Implications of these findings are discussed. / acase@tulane.edu

Children with autism spectrum disorder show imaginative and representational drawing deficits, despite reports of a “visual thinking style”. I examined whether these two drawing characteristics could be explained by the unique cognitive style of children with autism (specifically, executive dysfunction and a local processing bias). I administered a cognitive/drawing task battery to a group of 24 school-age children with autism and 29 mental age-matched neurotypically developing controls. I expected that better executive function ability would be associated with better imaginative and representational drawing, and that a local processing bias (weak central coherence) would be associated with better representational drawing but worse imaginative drawing. In children with autism, better executive function was associated with better imaginative drawing. Greater central coherence was associated with better representational drawing, but executive function was associated with worse representational drawing. Underlying cognitive components of imaginative and representational drawing were different for the neurotypically developing children. Overall, findings were unexpected, leading to novel theoretical suggestions for the field of autism cognition and drawing research. / Graduate / 0620 / 0623 / kd.teneycke@gmail.com

<p>Savant syndrome is a rare condition in which some people have extraordinary talents despite some serious mental or physical disability. It is a syndrome with remarkable features, standing in stark contrast to a person’s overall character. The term savant, or idiot savant, describes a person who, in spite of low intelligence, has a skill in some specific narrow area. Savants can have a specific talent in, for instance, music, art, calendar calculation or foreign language but whatever the specific talent is, it is always connected to extraordinary memory. Savant syndrome seems to be also connected to autism or autistic characteristics. In this paper I aim to give a clear description of the savant syndrome and explain its connection to autism. Further, I present how specific theories try to describe the causes of savant syndrome, and connect the theories to results of empirical research in order to give an overall view of the syndrome’s appearance. I will also compare the theories and evaluate their strengths and weaknesses with respect to the discoveries and progress that has been made within the area of savant syndrome research.</p>

The aim of the present thesis was twofold, first to map the semantic memory decline in Alzheimer patients over time, second to take the patient’s perspective and create a multifaceted picture of the individual with Alzheimer’s disease through the study of memory, awareness, central coherence and emotions. Further issues concerned how Alzheimer individuals handled their cognitive erosion in everyday life and if they were well calibrated with their spouse in disease related matters. Two studies were performed, the first involved a longitudinal study of sematic deterioration, the second had a mixed methods design involving both quantitative and qualitative measures as in neuropsychological assessment and interviews. Through the longitudinal study it could be concluded that the nature of semantic deterioration is best described as loss of memory information rather than problems in accessing the information. It was further concluded that semantic concepts gradually lose their specific features during course of illness. The results from the second study revealed that the Alzheimer individuals were aware of their disease although they could not foresee the implications of their cognitive shortcomings in their everyday life. They evidenced weak central coherence, in that they were unable to infer details into a meaningful whole. This implies that they perceive their surrounding world in a fragmented way as consisting of separate objects rather than a comprehensible context. Concerning emotions it was found that they responded to negatively valenced words in the same way as normal ageing individuals, although being impaired in their response to positively and neutral words. Finally, the Alzheimer individuals and their spouses were not well calibrated regarding disease related issues. The findings of the present thesis have important clinical implications and gives valuable input to the understanding of the individual with Alzheimer’s disease. / Föreliggande avhandling hade två huvudsyften; dels att kartlägga försämringen av semantiskt minne hos Alzheimerpatienter över tid; dels att ta patientens perspektiv och skapa en mångfacetterad bild av individen med Alzheimers sjukdom. Fyra begrepp studerades i relation till detta, nämligen minne, medvetande, central koherens och emotioner. Ytterligare aspekter som studerades var hur Alzheimerindivider hanterar sina kognitiva tillkortakommanden i sin vardag samt hur väl kalibrerade de är med sin make/maka angående sjukdomsrelaterade frågor. Två studier genomfördes varav den första var en longitudinell studie av semantisk minnesförsämring och den andra hade en ’mixed methods’ design, inkluderande både kvantitativa (neuropsykologiska tester) och kvalitativa (intervjuer) metoder. Resultaten från den longitudinella studien avslöjade att semantiska begrepp som inte längre är välrepresenterade hos individen har gått förlorade snarare än att det skulle vara från om att individerna inte kan plocka fram informationen. Vidare kunde konstateras att semantiska begrepp gradvis tappar sina nyanser i takt med att sjukdomen fortskrider. Den andra studien visade att Alzheimerindividerna var medvetna om sin sjukdom och sina minnesproblem men att de inte kunde förutsäga vilka problem deras kognitiva tillkortakommanden skapade i deras vardag. De konstaterades ha svag central koherens vilket innebär att de ser sin omgivning på ett fragmentariskt sätt utan att kunna få ihop de olika objekten runt omkring sig till en meningsfull kontext. Vad gäller emotioner så kunde konstateras att Alzheimerindivider reagerar likadant som normalt åldrande individer på negativt laddade ord men att de är signifikant försämrade i förmågan att känna igen positiva och neutrala ord. Alzheimerindividerna och deras make/maka var inte väl kalibrerade vad gäller sjukdomsrelaterade frågor. Avhandlingens resultat har viktiga kliniska implikationer och ger ett värdefullt bidrag till förståelsen av en individ med Alzheimers sjukdom.

Savant syndrome is a rare condition in which some people have extraordinary talents despite some serious mental or physical disability. It is a syndrome with remarkable features, standing in stark contrast to a person’s overall character. The term savant, or idiot savant, describes a person who, in spite of low intelligence, has a skill in some specific narrow area. Savants can have a specific talent in, for instance, music, art, calendar calculation or foreign language but whatever the specific talent is, it is always connected to extraordinary memory. Savant syndrome seems to be also connected to autism or autistic characteristics. In this paper I aim to give a clear description of the savant syndrome and explain its connection to autism. Further, I present how specific theories try to describe the causes of savant syndrome, and connect the theories to results of empirical research in order to give an overall view of the syndrome’s appearance. I will also compare the theories and evaluate their strengths and weaknesses with respect to the discoveries and progress that has been made within the area of savant syndrome research.

Bien que les troubles du langage formel affectent une grande partie des enfants avec Trouble du Spectre Autistique (TSA), leur nature reste encore incertaine. Certaines études postulent que le trouble observable chez ces enfants est de même nature que celui dont souffrent les enfants avec trouble spécifique du langage (TSL), tandis que d’autres argumentent en faveur de deux troubles qui diffèrent dans leur étiologie. Au centre de ce débat réside la complexité à recueillir des données sur le langage chez les enfants avec TSA, notamment quand il s’agit de participer de manière active. Dans cette étude, nous explorons l’interprétation en temps réel des indices grammaticaux chez des enfants avec TSA monolingues francophones, en nous intéressant aux pronoms clitiques objets, dont la faible production en contexte obligatoire a été proposée comme marqueur du TSL pour le français. / It is well-known that children with Autism Spectrum Disorder (ASD) often have language impairment. However, the nature of this impairment is still largely unknown. Some studies hold that language impairment in children with ASD is of the same nature as impairment found in children with Specific Language Impairment (SLI), whereas others argue that SLI and language impairment in ASD may be different both in their structure and their etiology. At the heart of this debate lies the difficulty of assessing language abilities of children with ASD, especially when active participation is required. Moreover, to date, few studies have investigated formal aspects of language in children with ASD in languages other than English. In this study, we explore real-time interpretation of grammatical cues in French-speaking children with ASD, with a focus on object clitics.

The dissertation thesis addresses the topic of mathematical tasks processing in students with autism spectrum disorder (ASD) and problematic points of their solution. The aim of this work is to delineate methods that ASD students use to approach these tasks and solve them. We focus primarily on whether it is possible to identify different procedures than those used by typically developing students, and whether these procedures show specifics corresponding to distinct cognitive processes. In the theoretical part we provide a theoretical background for the study. Firstly, we create a frame to understand the complexity of autism, furthermore we deal with psychological theories examining the topic, and describe specifics of development of ASD students during their adolescence. Thereafter, we reflect on studies addressing mathematical skills of ASD students. Mathematics is considered as their great strength, however is not sufficiently scrutinized, as highlighted by various international studies (for example Oswald et al., 2016). The empiric part is based on qualitative methodology and pursues comparisons of mathematical tasks processing between six ASD students and typically developing peers. We strive to document differences and common points in solutions as well as to analyze cognitive processes of...