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A Genotype Resource for Postmortem Brain Samples from the Autism Tissue Program (Research Article, Accepted November 12)

Richard F. Wintle, Anath C. Lionel, Pingzhao Hu, Stephen D. Ginsberg, Dalila Pinto, Bhooma Thiruvahindrapduram, John Wei, Christian R. Marshall, Jane Pickett, Edwin H. Cook, and Stephen W. Scherer

LAY ABSTRACT

Autism is a complex disorder, in which there is a strong familial predisposition. Many studies have been performed examining behaviour, anatomy and chemistry of the central nervous system, and the inheritance (genetics) of the spectrum of autistic disorders. One initiative, the Autism Tissue Program, has banked brain samples donated after death, for research use. Our study has extracted DNA from these brain samples, and analyzed them for millions of genetic “markers”, in hope that this information can provide insight into the findings of other studies. We have also identified some rare changes in the DNA that may be associated with autism susceptibility, and point to specific genes that may be involved. Nevertheless, our main focus is in providing an ongoing resource of genetic data to the autism research community, so that other researchers can correlate their findings with genetic variation that we have described. All of these data are available to researchers through a peer-reviewed approval process used by the Autism Tissue Program, to ensure appropriate and ethical use of this information. © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 89–97. DOI: 10.1002/aur.173

Cardiac Responses to an Emotional Stroop Task in Medicated and Unmedicated Adults with Autism Spectrum Disorders (Research Article, Accepted November 11)

Karen J. Mathewson, Irene E. Drmic, Michelle K. Jetha, Susan E. Bryson, Joel O. Goldberg, Geoffrey B. Hall, Diane L. Santesso, Sidney J. Segalowitz, and Louis A. Schmidt

LAY ABSTRACT

For adults with autism spectrum disorder (ASD), the cardiovascular system may be in an over-aroused state. Why this would be is not known, but medications frequently prescribed for ASD could be an important factor. We compared cardiac functioning in a non-clinical group, and a group of adults with ASD, half of whom were taking antipsychotic medications and half of whom were not. Test conditions included quiet rest and performing a “Stroop” task that requires attending to the color of colorized emotional faces while ignoring their expressions. At rest and during task performance, heart rates were more relaxed in the control group than in the medicated ASD group, with no difference between control and ASD participants who were medication-free. Heart rates increased in all groups for Stroop performance, but greater autonomic adjustment was linked to better performance (faster responses) only among control participants. Results suggest that being able to appropriately adjust autonomic control when necessary may have helped non-clinical participants, either to avoid being “captured” by the distracting emotional faces or to generate color names more quickly. The relation was reversed in the unmedicated ASD group and absent in the medicated ASD group. Clearly, the effects of medication should be considered when studying psychological or physiological functioning in ASD. © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 98–108. DOI: 10.1002/aur.176

Probabilistic Reinforcement Learning in Adults with Autism Spectrum Disorders (Research Article, Accepted November 24)

Marjorie Solomon, Anne C. Smith, Michael J. Frank, Stanford Ly, and Cameron S. Carter

LAY ABSTRACT

Background: Autism spectrum disorders (ASDs) can be viewed as disorders of learning, but there have been relatively few experimental studies in this area. Methods: We examined probabilistic reinforcement learning performance of 28 adults with ASDs and 30 typically developing adults on a task requiring learning relationships between three stimulus pairs consisting of Japanese characters with feedback that was valid with a different probability (80%, 70% and 60%). We analyzed data using traditional methods as well as those that are used more commonly in the animal literature. Results: Both groups were able to learn the task. However there were group differences in early learning. In the first task block, individuals with ASDs acquired the most frequently accurately reinforced stimulus pair (80%) comparably to typically developing individuals; exhibited poorer acquisition of the less frequently reinforced 70% pair using one method of analysis (although this was not found when using a second method); but outperformed typically developing individuals on the near chance (60%) pair. Individuals with ASDs also demonstrated deficits in using positive feedback. Conclusions: Individuals with ASDs exhibit strengths and challenges in early probabilistic reinforcement learning suggesting deficits in the neural circuits involved in effortful early learning. One way to explain these results using what is known about neurobiology and a computer simulation model is that ASDs involve impairments in the functioning of the prefrontal cortex with compensation by the basal ganglia and other brain regions. This hypothesis can be tested with functional magnetic resonance imaging (fMRI). © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 109–120. DOI: 10.1002/aur.177

Towards Specifying Pervasive Developmental Disorder—Not Otherwise Specified (Research Article, Accepted November 24)

William Mandy, Tony Charman, Jane Gilmour, and David Skuse

LAY ABSTRACT

Pervasive developmental disorder – not otherwise specified (PDD-NOS) is the most common and least satisfactory of the PDD diagnoses. It is not clearly defined in the diagnostic manuals, limiting the consistency with which it is used by researchers and clinicians. This in turn limits the amount that we have learned about individuals with PDD-NOS. In a sample of 256 young people (mean age=9.1 years) we aimed to implement a clear, transparent definition of PDD-NOS, and then to describe those receiving this diagnosis (n=66), investigating whether they differed from people with autistic disorder (n=97) and Asperger's disorder (n=93). Groups were compared on measures of core PDD symptomatology, associated autistic features, and intelligence. Contrary to the assumption that PDD-NOS is heterogeneous, almost all (97%) of those with PDD-NOS had one distinct symptom pattern, namely impairments in social communication, without significant repetitive and stereotyped behaviours (RSB). Compared to autistic disorder and Asperger's disorder, they had comparably severe but more circumscribed social communication difficulties, with fewer non-social features of autism, such as sensory, feeding and visuo-spatial problems. These individuals appear to have a distinct variant of autism that does not merely sit at the less severe end of the same continuum of symptoms. The current draft guidelines for DSM-V, which insist on the presence of RSBs for any PDD diagnosis, would exclude such people from the autistic spectrum. © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 121–131. DOI: 10.1002/aur.178

Deficits in Adults with Autism Spectrum Disorders When Processing Multiple Objects in Dynamic Scenes (Research Article, Accepted December 1)

Kirsten O'Hearn, Laura Lakusta, Elizabeth Schroer, Nancy Minshew, and Beatriz Luna

LAY ABSTRACT

People with autism spectrum disorder (ASD) process visual information in a manner that is distinct from typical individuals. They may be less sensitive to people's goals, and focus on individual elements more than on the overall scene. To examine these differences, we tested the ability of people with and without ASD to detect changes in dynamic scenes with multiple elements, which sometimes included a person. Such scenes reflect more accurately the complexity of visual information in the real world than do static scenes or pictures. Changes were to the moving figure (person or inanimate object) or to the stationary inanimate objects at the beginning or end of the movement. We predicted that—when the figure was a person—typical developing individuals would detect changes in the end object (the “goal”) more accurately than other changes, but that this goal bias might not be evident in ASD. Alternately, people with ASD might attend to fewer elements regardless of whether the figure was a person. Contrary to our predictions, individuals with ASD displayed a similar goal bias as controls. However, adults with ASD were less sensitive to changes in the start and end objects than controls for all types of scenes. Importantly, these differences were evident in adults only, not children and adolescents, with ASD. These limitations impact the ability to see all the potentially important objects in complex scenes; that they emerge with development indicates that ASD affects the maturation of visual processes, and that adolescence is an important stage to study. © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 132–142. DOI: 10.1002/aur.179

Increased Rates of Depressed Mood in Mothers of Children with ASD Associated with the Presence of the Broader Autism Phenotype (Short Report, Accepted October 12)

Brooke Ingersoll, Katherine Meyer, and Mark W. Becker

LAY ABSTRACT

This study examined the relationship between the broader autism phenotype (BAP) and depressed mood in mothers of children with and without ASD. 165 mothers (71 with an ASD child, 94 with a non-ASD child) completed a survey of child autism severity (ASD mothers only), parenting stress, broader autism phenotype, and depression. Mothers of children with ASD reported greater depressed mood, higher parenting stress, and more characteristics associated with the BAP than mothers of children without ASD. The BAP and parenting stress were related to depressed mood in both groups. These findings suggest that the higher rate of depression found in mothers of children with ASD may be attributed both to the increased stress of raising a child with ASD, as well as a greater number of autistic features in the mothers that may place them at higher risk for developing depression. © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 143–148. DOI: 10.1002/aur.170

Developing the Frith-Happé Animations: A Quick and Objective Test of Theory of Mind for Adults with Autism (Short report, Accepted November 12)

Sarah J. White, Devorah Coniston, Rosannagh Rogers, and Uta Frith

LAY ABSTRACT

It is now widely accepted that individuals with autism have difficulties understanding other people's thoughts and feelings, an ability commonly known as mentalising. Mentalising ability has traditionally been assessed with tasks in which one person has a false belief about the state of the world or about another person's thoughts or actions. More recently, silent geometric animations portraying mental interactions between moving triangles have been found to be more sensitive in detecting these difficulties with high-functioning individuals; however, analysis of participants' verbal descriptions of these animations is time consuming and subjective. Here, we developed and tested a new objective method of response involving a series of multiple-choice questions. 16 adults with autism spectrum disorder and 15 typically-developing adults took part, matched for age and intelligence. The participants categorised a series of animations as to whether they involved a mental or physical interaction or whether no interaction had occurred, and selected the emotion felt by each triangle in those involving mental interactions. The adults with autism were less accurate at categorising the animations into whether a mental or physical interaction occurred or whether no interaction was observed. Furthermore, they were less able to select the correct emotions felt by the triangles in animations involving mental interactions. This new objective method for assessing understanding of the animations succeeded in being as sensitive as the original subjective method, as it was still able to detect mentalising difficulties in autism, as well as being quicker and easier to administer and analyze. © 2011 INSAR/Wiley Periodicals, Inc.

Article Citation:Autism Res2011, 4: 149–154. DOI: 10.1002/aur.174