Billstedt, E., Gillberg, I. C., & Gillberg, C. (2005). Autism after Adolescence: Population-based 13- to 22-year Follow-up Study of 120 Individuals with Autism Diagnosed in Childhood. Journal of Autism and Developmental Disorders, 35, 351-360.
ABSTRACT: Individuals with autism demonstrate impairments on measures of executive function (EF) relative to typically developing comparison participants. EF is comprised of several processes including inhibition, working memory and set shifting that develop throughout the lifespan. Impairments in EF may appear early in development and persist, or may represent a more transient delay which resolves with time. Given the unevenness of the cognitive profile of persons with autism, understanding the development of EF poses methodological challenges. These issues include those related to matching measures and the choice of comparison participants to which the performance of persons with autism will be compared. In the current review, we attempt to break down the processes of inhibition, working memory and set shifting among persons with autism. We propose to do this within a developmental perspective that highlights how matching measures and comparison participants can affect the interpretation of research findings. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Bogte, H., Flamma, B., van, d. M., Jaap, & van, E., Herman. (2008). Cognitive flexibility in adults with high functioning autism. Journal of Clinical and Experimental Neuropsychology, 30(1), 33-41.
ABSTRACT: The goal of the current study was to evaluate presetting, response inhibition, set shifting, and a priori planning in autism: abilities that can be lumped together under the term cognitive flexibility. Cognitive flexibility is an aspect of executive functioning, which in turn is mediated by the prefrontal cortical lobes. A group of adults with high-functioning autism (HFA; n=23) were compared with a normal control group (n=32), by using a computerized variant of the Sternberg response bias paradigm. Contrary to the results of earlier studies, no deficit was found in presetting, response inhibition, set shifting, and a priori planning in participants with autism, even when the medication factor was taken into account. Methodological issues that could be explanatory for this difference are discussed. An additional finding was, that individuals with HFA (especially those on medication) were slow in reacting. Possible origins and consequences of this slowness, also for cognitive flexibility, are discussed. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Boucher, J. (2007). Memory and generativity in very high functioning autism: A firsthand account, and an interpretation. Autism, 11, 255-264.
ABSTRACT: JS is a highly able person with Asperger syndrome whose language and intellectual abilities are, and always have been, superior. The first part of this short article consists of JS's analytical account of his atypical memory abilities, and the strategies he uses for memorizing and learning. JS has also described specific difficulties with creative writing, which are outlined here. The second part of the article consists of an interpretation of the problems JS describes in terms of their implications for understanding the problems of generativity that contribute to the diagnostic impairments of imagination and creativity in autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Brosnan, M. J., Scott, F. J., Fox, S., & Pye, J. (2004). Gestalt processing in autism: Failure to process perceptual relationships and the implications for contextual understanding. Journal of Child Psychology and Psychiatry, 45, 459-469.
ABSTRACT: Deficits in autism have been characterised as a bias towards local over global processing. This paper examines whether there is a deficit in gestalt grouping in autism. Method: Twenty-five low-functioning children with autism and 25 controls who were matched for chronological age and verbal mental age took part in the study. Results: The autism group utilised gestalt grouping principles (proximity, similarity, closure) significantly less than the controls. Calculating an overall index of gestalt grouping, the autism group performed at chance level. There was also a deficit in identifying certain impossible figures. This pattern was not reflected in a drawing task, in which the autism sample conformed more to gestalt grouping principles than controls (non-significantly). Conclusions: The results are discussed in terms of a failure in autism to process inter-element relationships that would allow for the appreciation of larger perceptually coherent units that comprise of multiple elements and, consequently, context. The processes are argued to be preattentive. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Burack, J. A. (1994). Selective attention deficits in persons with autism: Preliminary evidence of an inefficient attentional lens. Journal of Abnormal Psychology, 103, 535-543.
ABSTRACT: A forced-choice reaction time (RT) task was used to assess the filtering component of selective attention in mental-age (MA) matched groups of persons with autism (n = 12), organic mental retardation (n = 32), familial mental retardation (n = 30), and no handicap (n = 34). Conditions varied with regard to the presence or absence of a window and number (zero, two, or four) and location of distractors. The RTs of the persons with autism improved relative to the other groups in the presence of the window without distractors, but this effect was negated when distractors were also presented. The performance of the persons with autism was the most impaired in the presence of distractors. These findings represent preliminary behavioral evidence of an inefficient attentional lens among persons with autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Cashin, A., & Waters, C. (2006). The Undervalued Role of Over-regulation in Autism: Chaos Theory as a Metaphor and Beyond. Journal of Child and Adolescent Psychiatric Nursing, 19, 224-230.
ABSTRACT: A triad of impairment that consists of impaired communication, impaired social skills and over-regulated behavior characterizes autism. Causality of autism is yet to be identified. Therapy has been devised to apply to the work with children and adolescents with a diagnosis of autism in the domains of impaired communication and impaired social skills. Little attention has been paid to the importance of the over-regulated behavior that forms part of the triad of impairment. Purpose: This paper considers this point of over-regulation in the triad of impairment in autism through the lens of Chaos theory. Sources: Contemporary literature on autism and Chaos theory. Conclusions: Implications for nursing practice and research are raised. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Delorme, R., Gouss˝, V., Roy, I., Trandafir, A., Mathieu, F., Mouren, S., Marie Christine et al. (2007). Shared executive dysfunctions in unaffected relatives of patients with autism and obsessive-compulsive disorder. European Psychiatry, 22, 32-38.
ABSTRACT: Executive dysfunctions have been studied as a potential endophenotype associated with the genetic basis of autism. Given that recent findings from clinical and molecular genetic studies suggest that autism and obsessive-compulsive disorder (OCD) could share a common pattern of heritability, we assessed executive functions as a possible common cognitive endophenotype in unaffected family members of individuals with either autism or OCD. Methods: Five tests assessing executive functions (Tower of London, verbal fluency, design fluency, trail making and association fluency) were proposed to 58 unaffected first-degree relatives (parents and siblings) of probands with autism and 64 unaffected first-degree relatives of OCD patients. Results were compared with those of 47 healthy controls matched for age, sex, and level of education. Results: In the Tower of London test, both groups of unaffected relatives showed significantly lower scores and longer response times compared with controls. No differences were observed between autism and OCD relatives and healthy controls in the four other tasks (verbal fluency, design fluency, trail making test and association fluency). Conclusions: Our findings show the existence of executive dysfunction in the unaffected first-degree relatives of probands with OCD, similar to those observed in the relatives of patients with autism. These results support and extend previous cognitive studies on probands indicating executive dysfunctions in autism and OCD. Planning and working memory processes could thus represent a common cognitive endophenotype in autism and OCD that could help in the identification of genes conferring vulnerability to these disorders. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Gastgeb, H. Z., Strauss, M. S., & Minshew, N. J. (2006). Do Individuals With Autism Process Categories Differently? The Effect of Typicality and Development. Child Development, 77, 1717-1729.
ABSTRACT: This study examined the effect of exemplar typicality on reaction time and accuracy of categorization. High-functioning children (age 9-12), adolescents (age 13-16), and adults with autism (age 17-48) and matched controls were tested in a category verification procedure. All groups showed improved processing throughout the lifespan for typical and somewhat typical category exemplars. However, individuals with autism responded more slowly than matched controls to atypical exemplars at all ages. The results are discussed in terms of potential differences in the type of processing that may be required for categorizing typical and atypical category exemplars. Parallels are also drawn to the results of previous studies on face processing in individuals with autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Geurts, H. M., Vert˝, S., Oosterlaan, J., Roeyers, H., & Sergeant, J. A. (2004). How specific are executive functioning deficits in attention deficit hyperactivity disorder and autism? Journal of Child Psychology and Psychiatry, 45, 836-854.
ABSTRACT: The objective of this study is to identify intact and deficient cognitive processes in children with attention deficit hyperactivity disorder (ADHD) and children with high functioning autism (HFA). Method: Three rigorously diagnosed groups of children aged between 6 and 12 years (54 ADHD, 41 HFA, and 41 normal controls) were tested on a wide range of tasks related to five major domains of executive functioning (EF): inhibition, visual working memory, planning, cognitive flexibility, and verbal fluency. In addition, the role of comorbid oppositional defiant disorder (ODD) and comorbid conduct disorder (CD) in ADHD was investigated by directly comparing 20 children with ADHD and 34 children with comorbid ADHD + ODD/CD. Results: ADHD was associated with EF deficits in inhibiting a prepotent response and verbal fluency. Children with HFA demonstrated deficits in all EF domains, except interference control and working memory. The HFA group showed more difficulties than the ADHD group with planning and cognitive flexibility. The comorbid ADHD + ODD/CD group did not show a distinctive pattern of performance on the EF tests compared to the ADHD group. Conclusion: The present study indicates that children with HFA exhibit more generalised and profound problems with EF tasks... (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Goldberg, M. C., Mostofsky, S. H., Cutting, L. E., Mahone, E. M., Astor, B. C., Denckla, M. B. et al. (2005). Subtle Executive Impairment in Children with Autism and Children with ADHD. Journal of Autism and Developmental Disorders, 35, 279-293.
ABSTRACT: The executive functions of inhibition, planning, flexible shifting of actions, and working memory are commonly reported to be impaired in neurodevelopmental disorders. Method: We compared these abilities in children (8-12 years) with high functioning autism (HFA, n = 17), attention deficit-hyperactivity disorder (ADHD, n = 21) and healthy controls (n = 32). Response inhibition was assessed using the Stroop Color and Word Test (Golden, 1978). Problem solving, set-shifting, and nonverbal memory were assessed using three tasks, respectively, from the CANTAB˝ (Cambridge Cognition, 1996): the Stockings of Cambridge task; the Intra-Dimensional/Extra-Dimensidnal set-shifting task; and the Spatial Working Memory task (SWM) with tokens hidden behind 3, 4, 6, and 8 boxes. Results: There were no group differences on the response inhibition, planning, or set-shifting tasks. On the SWM task, children with HFA made significantly more between-search errors compared with controls on both the most difficult problems (8-box) and on the mid-difficulty problems (6-box); however, children with ADHD made significantly more errors compared to controls on the most difficult (8-box) problems only. Conclusion: Our findings suggest that spatial working memory is impaired in both ADHD and HFA, and more severely in the latter. More detailed investigation is needed to examine the mechanisms that differentially impair spatial working memory, but on this set of tasks there appears to be sparing of other executive functions in these neuropsychiatric developmental disorders. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Goldstein, G., Allen, D. N., Minshew, N. J., Williams, D. L., Volkmar, F., Klin, A. et al. (2008). The structure of intelligence in children and adults with high functioning autism. Neuropsychology, 22(3), 301-312.
ABSTRACT: Confirmatory factor analyses of the commonly used 11 subtests of the Wechsler child and adult intelligence scales were accomplished for 137 children and 117 adults with high functioning autism (HFA) and for comparable age groups from the standardization samples contained in the Wechsler manuals. The objectives were to determine whether the structure of intelligence in HFA groups was similar to that found in the normative samples, and whether a separate "social context" factor would emerge that was unique to HFA. Four-factor models incorporating a Social Context factor provided the best fit in both the autism and normative samples, but the subtest intercorrelations were generally lower in the autism samples. Findings suggest similar organization of cognitive abilities in HFA, but with the possibility of underconnectivity or reduced communication among brain regions in autism. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Hala, S., Rasmussen, C., & Henderson, A. M. E. (2005). Three Types of Source Monitoring by Children With and Without Autism: The Role of Executive Function. Journal of Autism and Developmental Disorders, 35, 75-89.
ABSTRACT: Earlier investigations have found mixed evidence of source monitoring impairment in autism. The present study examined three types of source monitoring ability in children with autism and typically developing children. In three different conditions, participants were presented with word lists after which they were required to recall the source of the word for reality, external and internal source monitoring tasks. Group differences were found across all three conditions, with the comparison group outperforming the children with autism. The pattern of performance across the three conditions, however, was comparable for the two groups. Specifically, performance was higher on the reality monitoring task than either the external or internal source tasks. We suggest that the overall impairment found for the children with autism may be due to broader impairments in executive function. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Happe', F., & Booth, R. (2008). The power of the positive: Revisiting weak coherence in autism spectrum disorders. The Quarterly Journal of Experimental Psychology, 61(1), 50-63.
ABSTRACT: This paper reexamines Frith's original concept of weak coherence, its historical origins, recent reformulations, and alternative accounts. We suggest that the key notion of reduced global integration of information, which Frith proposed to underlie the assets in local processing, has been neglected in recent accounts of autism spectrum disorders (ASD). In fact, most paradigms used to test weak coherence conflate global and local processing, often placing them in direct trade-off, so that it is not possible to tell whether patterns of performance in ASD reflect reduced global processing, increased local processing, or both. We review the literature from typical development and ASD that may be pertinent to this distinction and examine some data from our own studies. Only once tasks are devised that measure separately the effects of reduced global processing and increased local processing will it be possible to test the on-line and developmental relations between these two aspects of "weak coherence". Some preliminary ideas about these relationships are discussed, and suggestions are made for why disentangling two possibly independent dimensions of weak coherence may be timely and productive. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Hobson, R. P. (2007). On being moved in thought and feeling: An approach to autism. New developments in autism: The future is today., 139-154.
ABSTRACT: I can explain the title of this chapter, 'On being moved in thought and feeling: An approach to autism', because I want to approach the question 'What is autism?' from a fresh starting-point, one that encompasses a particular view of typical development. The view is that early interpersonal experience is critically important for the acquisition of cognitive as well as social abilities. On the other side to this coin is a thesis about what makes autism 'autism'. The thesis is closely allied to Kanner's (1943) suggestion that the children have 'inborn disturbances of affective contact'. The story is one that focuses both on what individual children lack by way of the necessary equipment to achieve fully-fledged intersubjective engagement with others, and what follows by way of interference with the kinds of interpersonal process that normally promote flexibility in children's thinking and attitudes. The central idea is that being moved by others--and here I am talking about movement in subjective orientation, especially as these involve feelings and attitudes--is one of the most significant features of human social life. It is foundational for experiencing people as people with their own subjective orientations to the world, for evolving forms of self-other awareness, for the construction of increasingly sophisticated concepts about the mind ('theory of mind'), for self-reflection and aspects of executive functioning, and for the kinds of symbolic functioning and flexible stance in relation to the world that contribute so much to human creativity in thinking and action. Of course it will not be possible for me to argue for each and every one of these claims. I have tried to do so in two books (Hobson 1993, 2002), of which the most recent (The Cradle of Thought) is intended to be reader-friendly to a wide audience. What I shall try to do in this contribution is to illustrate what I mean by 'being moved'. I shall do this by citing specific studies, mainly but not exclusively conducted in the Developmental Psychopathology Research Unit, Tavistock Clinic and University College London. En route, I shall offer some reflections on the implications of the findings for our notion of what is 'basic' to autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Hughes, C., Russell, J., & Robbins, T. W. (1994). Evidence for executive dysfunction in autism. Neuropsychologia, 32, 477-492.
ABSTRACT: Administered 2 tests of executive function to autistic Ss and control Ss to show that impairments in executive control (EC) also exist in the larger population of less able individuals with autism. 35 autistic Ss (aged 7-18 yrs) and 2 control groups of 38 nonautistic Ss with moderate learning disabilities (MLDs) and 47 normal Ss completed an intradimensional-extradimensional set-shifting test. 30 autistic Ss (aged 8-19 yrs), 37 Ss with MLDs, and 44 normal Ss completed the Tower of London planning task. On each task, autistic Ss were differentially impaired with respect to controls. This impairment was specific to the stages of each task that placed greatest demands on EC. Results demonstrate significant executive dysfunction in autism in the domains of attentional set-shifting and planning. The lack of association between performances on the 2 tasks suggests separable elements of EC. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Iarocci, G., I. (2003). Global and local perception in autism: The role of basic and higher-order attention. Univ Microfilms International, US.
ABSTRACT: This study focused on specific conceptual, methodological and developmental issues pertinent to investigating the role of attention in global-local processing among high-functioning children with autism (average verbal mental age (MA) of 89 months and nonverbal MA of 116 months) as compared to their verbal and nonverbal MA matched peers. Two experiments were conducted to assess separately basic processing; focal attention that is drawn by the physical properties of the stimuli and higher-order processing associated with strategically directing attention in accordance with the observer's priorities within a given task. These components of attention are implicated in the typical development of global-local perceptual organization. In Experiment 1, a visual search task was used to explore the role of basic focal attention to perceptually group dots at either a long or short spatial range. In Experiment 2, a visual search and target identification task was used to assess higher-order voluntary control of attention to the global or the local level of a hierarchical geometric pattern. To assess changes in voluntary attending to a specific target level, an implicit manipulation of increased probability of the target appearing at the global or local level or equally at both levels was included. The main finding was that high-functioning children with autism and their verbal and nonverbal MA matched peers showed comparable focused attention to perceptually organize stimuli over a short or long spatial range but different higher-order attentional processing of hierarchical global-local targets. In all groups, search efficiency for long range targets decreased as a function of display size but the search for short range targets was efficient regardless of display size. Long range grouping performance involves goal-driven, focused attention that is constrained by serial inspection whereas the short range grouping performance implicates a sensory-driven, preattentive spatial-indexing mechanism. At higher levels of attentional control, high-functioning children with autism show a preference for using a local attentional strategy whereas their typically developing peers rely on a global attentional strategy to search for hierarchical global-local targets among distractors. The particular style of visual processing used to search for targets was not influenced by implicit changes in the probability of a target appearing at the local or global level. The findings support the interpretation that a perceptual disturbance in global-local processing in persons with autism may be associated with different higher-order strategy-based processing rather than an enhanced ability to integrate features. (PsycINFO Database Record (c) 2004 APA, all rights reserved)
Johnson, K. A., Robertson, I. H., Kelly, S. P., Silk, T. J., Barry, E., D˝ibhis, A. et al. (2007). Dissociation in performance of children with ADHD and high-functioning autism on a task of sustained attention. Neuropsychologia, 45, 2234-2245.
ABSTRACT: Attention deficit hyperactivity disorder (ADHD) and autism are two neurodevelopmental disorders associated with prominent executive dysfunction, which may be underpinned by disruption within fronto-striatal and fronto-parietal circuits. We probed executive function in these disorders using a sustained attention task with a validated brain-behaviour basis. Twenty-three children with ADHD, 21 children with high-functioning autism (HFA) and 18 control children were tested on the Sustained Attention to Response Task (SART). In a fixed sequence version of the task, children were required to withhold their response to a predictably occurring no-go target (3) in a 1-9 digit sequence; in the random version the sequence was unpredictable. The ADHD group showed clear deficits in response inhibition and sustained attention, through higher errors of commission and omission on both SART versions. The HFA group showed no sustained attention deficits, through a normal number of omission errors on both SART versions. The HFA group showed dissociation in response inhibition performance, as indexed by commission errors. On the Fixed SART, a normal number of errors was made, however when the stimuli were randomised, the HFA group made as many commission errors as the ADHD group. Greater slow-frequency variability in response time and a slowing in mean response time by the ADHD group suggested impaired arousal processes. The ADHD group showed greater fast-frequency variability in response time, indicative of impaired top-down control, relative to the HFA and control groups. These data imply involvement of fronto-parietal attentional networks and sub-cortical arousal systems in the pathology of ADHD and prefrontal cortex dysfunction in children with HFA. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Kaland, N., Smith, L., & Mortensen, E. L. (2008). Brief report: Cognitive flexibility and focused attention in children and adolescents with Asperger syndrome or high-functioning autism as measured on the computerized version of the Wisconsin Card Sorting Test. Journal of Autism and Developmental Disorders, 38(6), 1161-1165.
ABSTRACT: The aim of the present study was to assess mental flexibility and set maintenance of a group of individuals with Asperger syndrome (AS) or high-functioning autism (HFA) (N = 13; mean age 16,4), as compared with a matched group of typically developing children and adolescents (N = 13; mean age 15,6) on the computerized version of the Wisconsin Card Sorting Test (WCST). The participants in the AS/HFA group performed less well than the controls on all categories of the WCST, but the differences did not reach conventional statistical significance on most categories of the WCST. On the category failure to maintain set, however, the AS/HFA participants performed significantly less well than the controls, suggesting a deficit of focused attention. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Klin, A., Jones, W., Schultz, R., T., & Volkmar, F., R. (2005). The Enactive Mind-From Actions to Cognition: Lessons from Autism., 682-703.
ABSTRACT: This chapter begins with an intriguing puzzle posed by normative-IQ individuals with autism. One of the most intriguing puzzles posed by individuals with autism is the great discrepancy between what they can do on explicit tasks of social reasoning and what they fail to do in more naturalistic situations. This chapter examines the social world as an open-domain task, developmental and contextual elements in the emergence of mental representations, temporal constraints on models of social adaptation, social cognition as social action. Collectively, the various examples presented here suggest a need to explain the discrepancy between performance on structured and explicit as against naturalistic and spontaneous tasks and, in so doing, to explore what might be a unique social developmental path evidenced in autism. This chapter contends that theories of the social dysfunction in autism need to address both of these phenomena. The framework presented is called enactive mind (EM) to highlight the central role of motivational predispositions to respond to social stimuli and a developmental process in which social cognition results from social action. (PsycINFO Database Record (c) 2006 APA, all rights reserved)
Landa, R. J., & Goldberg, M. C. (2005). Language, Social, and Executive Functions in High Functioning Autism: A Continuum of Performance. Journal of Autism and Developmental Disorders, 35, 557-573.
ABSTRACT: This study examined language and executive functions (EF) in high-functioning school-aged individuals with autism and individually matched controls. Relationships between executive, language, and social functioning were also examined. Participants with autism exhibited difficulty on measures of expressive grammar, figurative language, planning, and spatial working memory. A mixed profile of impaired and enhanced abilities was noted in set-shifting. While controls showed the typical increase in errors when shifting sets from an intra-dimensional to an extra-dimensional stimulus, this pattern was not noted in participants with autism. Relationships between EF, language, and social performance were weak to nonexistent. Implications for theories of core deficit in autism and dissociable nature of the language and executive impairments in autism are discussed. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Landry, R., & Bryson, S. E. (2004). Impaired disengagement of attention in young children with autism. Journal of Child Psychology and Psychiatry, 45, 1115-1122.
ABSTRACT: The present study examined the disengage and shift operations of visual attention in young children with autism. Methods: For this purpose, we used a simple visual orienting task that is thought to engage attention automatically. Once attention was first engaged on a central fixation stimulus, a second stimulus was presented on either side, either simultaneously or successively. Latency to begin an eye movement to the peripheral stimulus served as the main dependent measure. The two stimulus conditions (simultaneous and successive) provided independent measures of disengaging and shifting attention, respectively. Performance of children with autism was compared to that of children with Down syndrome and a normal group. Results: The main finding was that relative to both comparison groups, children with autism had marked difficulty in disengaging attention. Indeed, on 20% of trials they remained fixated on the first of two competing stimuli for the entire 8-second trial duration. Evidence is also provided for a more subtle problem in executing rapid shifts of attention. Conclusions: Our findings on disengagement in autism parallel those reported in normal 2- month-olds, in whom attention has been described as 'obligatory.' Discussion focuses on the potential role of general versus domain-specific processes in producing some of the core features of autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Luna, B., Doll, S. K., Hegedus, S. J., Minshew, N. J., & Sweeney, J. A. (2007). Maturation of Executive Function in Autism. Biological Psychiatry, 61, 474-481.
ABSTRACT: Executive dysfunction has been reported at different ages in autism. It is not clear however, when this impairment emerges or how its expression is affected by development. Methods: 61 non-mentally retarded autism participants (AUT) and 61 age, gender, and IQ matched typically developing participants (CON) were assessed with two oculomotor executive function tasks, the oculomotor delayed response task (ODR) and the antisaccade task (AS), as well as a visually-guided saccade sensorimotor task (VGS). Results: The AUT group demonstrated impairments in response inhibition and spatial working memory at all ages tested. Developmental improvements in speed of sensorimotor processing and voluntary response inhibition were similar in both groups indicating sparing of some attentional control of behavior. Developmental progression in the speed of initiating a cognitive plan and maintaining information on line over time, however, was impaired in the AUT group indicating abnormal development of working memory. Conclusions: These results indicate that while executive dysfunction is present throughout development, there is evidence for both typical and atypical developmental progression of executive functions in autism. The plasticity suggested by the developmental improvements may have implications regarding appropriate developmental epochs and types of interventions aimed at enhancing cognitive capacities in individuals with autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Minshew, N. J., Sweeney, J., & Luna, B. (2002). Autism as a selective disorder of complex information processing and underdevelopment of neocortical systems. Molecular Psychiatry, 7, S14-S15.
ABSTRACT: Autism is now widely accepted as being a developmental neurobiologic disorder of polygenetic origin. The cause of autism is viewed as a cascade of events occurring across genetic, developmental neurobiologic, neural, cognitive and neurologic, and behavioral levels. The conceptualization of autism as a selective disorder of complex information processing identifies a common denominator of all the cognitive and neurologic manifestations of this syndrome, thus unifying the syndrome at a clinical level. The neural basis of the cognitive deficits in autism has been investigated with saccadic eye movements. The studies have provided evidence that autism is a disorder of information processing in general, and complex information processing in particular. They further demonstrated that these cognitive deficits are the result of dysfunction of neocortical systems and of the under incorporation of higher brain regions into these neural systems. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Ozonoff, S., South, M., & Provencal, S. (2007). Executive functions in autism: Theory and practice. New developments in autism: The future is today., 185-213.
ABSTRACT: The chapter also appeared in The Handbook of Autism and Pervasive Developmental Disorders, Volume 1, Diagnosis, Development, Neurobiology, and Behaviour, 3rd Edition, edited by F. R. Volkmar, R. Paul, A. Klin and D. J. Cohen. Executive function is the cognitive construct used to describe goal-directed, future-oriented behaviors thought to be mediated by the frontal lobes, including planning, inhibition of prepotent responses, flexibility, organized search, self-monitoring, and use of working memory. Executive dysfunction has been found in both individuals with autism and their family members, across many ages and functioning levels, on many different instruments purported to measure executive function. This chapter summarizes this still growing literature. We explore a number of issues that have emerged in the executive function literature as the field has matured, including the developmental trajectory of executive function, its relation to other cognitive abilities and features of autism, and its association with other neurodevelopmental disorders. We conclude the chapter with thoughts about future research directions, including new findings that executive dysfunction may be familial and suggestions for remediation. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Reed, T. (2002). Visual perspective taking as a measure of working memory in participants with autism. Journal of Developmental and Physical Disabilities, 14, 63-76.
ABSTRACT: Notes that there is mounting evidence that people with autism have executive function deficits and that those deficits are linked to the social impairment characteristic of autism. L. Bennetto et al. (1996) suggest that, more specifically, people with autism may have a deficit in working memory. This hypothesis was tested using a visual perspective-taking task whose working memory load could be systematically varied. Three groups of Ss participated in this study: participants with autism (aged 5.2-39.11 yrs; 10 of whom were also mildly retarded), participants with retardation (aged 3.1-17 yrs; who were not autistic), and typically developing participants (aged 6.4-52 yrs). The performance of participants with autism on this task was significantly worse than that of the control participants. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Rehfeldt, R. A., Dillen, J. E., Ziomek, M. M., & Kowalchuk, R. K. (2007). Assessing Relational Learning Deficits in Perspective-Taking in Children with High-Functioning Autism Spectrum Disorder. Psychological Record, 57, 23-47.
ABSTRACT: Perspective-taking, or the ability to demonstrate awareness of informational states in oneself and in others, has been of recent interest in behavioral psychology. This is, in part, a result of a modern behavioral approach to human language and cognition known as Relational Frame Theory, which views perspective-taking as generalized operant behavior based upon a history of reinforcement for relational responding. Previous lines of research have developed a behavioral protocol for assessing relational learning deficits in perspective-taking and have implicated the lack of perspective-taking as a basis for the social deficits observed in children with autism. However, no empirical investigations have been conducted on relational learning deficits in perspective-taking with autistic populations. The present paper reports 2 experiments that investigated whether children with autism spectrum disorder demonstrated relational learning deficits in a perspective-taking task as compared to their age-matched typically developing peers. We also investigated whether accuracy in perspective-taking correlated with scores on standardized instruments commonly used in the assessment of autism spectrum disorder, and whether relational responding in perspective-taking improves following a history of reinforcement for such responding. Results of Experiment 1 demonstrated statistically significant differences in errors as a function of type of relation, while visual inspection revealed that participants with autism spectrum disorder made more errors than typically developing children on 2 of the 3 types of relations examined. Results of Experiment 2 illustrated that a history of reinforced relational responding improved performance on the perspective-taking task. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Ruble, L. A., & Scott, M. M. (2002). Executive functions and the natural habitat behaviors of children with autism. Autism, 6, 365-381.
ABSTRACT: An ecological method first described by R. Barker and H. Wright and adapted by M. Scott was used to assess the patterns of goal-directed behaviors of 8 6-10 yr old males with autism and 8 chronological and mental age comparable children with Down syndrome. Quantitative and qualitative features of naturalistic behaviors were collected, and coded using previously described categories of children's behavior. Results indicate that children with autism exhibited shorter and less overlapping goal-directed behaviors. It is concluded that these data suggest a cognitive difference rather than developmental delay, and lend support for impaired executive functions in autism. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
Russo, N., Flanagan, T., Iarocci, G., Berringer, D., Zelazo, P. D., & Burack, J. A. (2007). Deconstructing executive deficits among persons with autism: Implications for cognitive neuroscience. Brain and Cognition, 65(1), 77-86.
ABSTRACT: Individuals with autism demonstrate impairments on measures of executive function (EF) relative to typically developing comparison participants. EF is comprised of several processes including inhibition, working memory and set shifting that develop throughout the lifespan. Impairments in EF may appear early in development and persist, or may represent a more transient delay which resolves with time. Given the unevenness of the cognitive profile of persons with autism, understanding the development of EF poses methodological challenges. These issues include those related to matching measures and the choice of comparison participants to which the performance of persons with autism will be compared. In the current review, we attempt to break down the processes of inhibition, working memory and set shifting among persons with autism. We propose to do this within a developmental perspective that highlights how matching measures and comparison participants can affect the interpretation of research findings. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Solomon, M., Ozonoff, S. J., Cummings, N., & Carter, C. S. (2008). Cognitive control in autism spectrum disorders. International Journal of Developmental Neuroscience, 26(2), 239-247.
ABSTRACT: Cognitive control refers to the ability to flexibly allocate mental resources to guide thoughts and actions in light of internal goals. Given the behavioral inflexibility exhibited by individuals with autism spectrum disorders (ASDs), it would appear they experience cognitive control deficits. Cognitive correlates of this behavioral inflexibility have been elusive in previous investigations. Study goals were to investigate deficits in cognitive control in ASDs; to explore its developmental trajectory; and to test whether control deficits are related to symptoms of inflexible thoughts and/or behaviors, and attention symptoms. Thirty-one children and adolescents aged 8-17 with ASDs and 32 age, IQ, and gender matched control subjects completed cognitive, diagnostic, and behavioral assessments, as well as a measure of cognitive control involving overcoming a prepotent response tendency. Compared with typically developing control subjects, individuals with ASDs exhibited deficits in cognitive control. Younger children with ASDs did not demonstrate age-related improvements in cognitive control. Modest relationships between cognitive control, IQ, and attention problems were found for the sample. Only the relationship between cognitive control and full-scale IQ survived correction for multiple comparisons. (PsycINFO Database Record (c) 2008 APA, all rights reserved)
Szatmari, P., Georgiades, S., Bryson, S., Zwaigenbaum, L., Roberts, W., Mahoney, W. et al. (2006). Investigating the structure of the restricted, repetitive behaviours and interests domain of autism. Journal of Child Psychology and Psychiatry, 47(6), 582-590.
ABSTRACT: The Restricted, Repetitive Behaviours and Interests (RRBIs) are represented in the DSM-IV and measured by the Autism Diagnostic Interview-Revised (ADI-R) as one of the three homogeneous symptom categories of Pervasive Developmental Disorders. Although this conceptualisation is well accepted in the field, the grouping of symptoms is based primarily on clinical judgment rather than on empirical evidence. Methods: The objective of this study was to examine the factor structure of the RRBI domain of autism. Eleven items from this domain of the ADI-R were used in a Principal Components Analysis (PCA). Our sample consisted of 339 individuals with a Best Estimate diagnosis of Pervasive Developmental Disorder (PDD). Results: Findings indicate that the RRBI domain is composed of two distinct factors or dimensions: Insistence on Sameness (IS) and Repetitive Sensory and Motor Behaviours (RSMB). RSMB is negatively correlated with adaptive skills; that is, lower functioning individuals tend to have higher levels of repetitive sensory and motor behaviours. On the other hand, IS is positively correlated with autistic symptoms in the communication and language domain. Further analyses suggest moderate familial aggregation among affected sibling pairs within the IS but not the RSMB factor. Conclusions: These results provide evidence for the heterogeneity of the RRBI domain of the ADI-R in terms of both clinical presentation and other correlates. In addition, the IS factor seems to be under familial (presumably genetic) control, while RSMB appears to simply reflect variation in developmental level. (PsycINFO Database Record (c) 2006 APA, all rights reserved)
Toichi, M., Kamio, Y., Okada, T., Sakihama, M., Youngstrom, E., A., Findling, R., L. et al. (2002). A lack of self-consciousness in autism. American Journal of Psychiatry, 159(8), 1422-1424.
ABSTRACT: Investigated self-consciousness in autism. An incidental memory task was conducted on 18 adults with high-functioning autism (mean age 23.0 yrs) and 18 normal comparison Ss (mean age 24.5 yrs). Three kinds of orienting questions (phonological, semantic, and self-referent, i.e., "Does the word describe you?") were asked about target words (adjectives for personality traits) in order to induce different types of processing. This was followed by an unexpected recognition test. Results show that while semantic processing resulted in better memory than phonological processing in both groups, self-referent processing yielded better memory performance than semantic processing in the comparison group but not in the autistic group. The results suggest deficits in self-consciousness in individuals with autism. (PsycINFO Database Record (c) 2004 APA, all rights reserved)