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Cognitive flexibility has been measured with inductive reasoning or explicit rule tasks in individuals with autism spectrum disorders (ASD). The Flexible Item Selection Task (FIST) differs from previous cognitive flexibility tasks in ASD research by giving children an abstract, ambiguous rule to switch. The ASD group (N = 22; Mean age = 8.28 years, SD = 1.52) achieved a lower shift percentage than the typically developing verbal mental-age control group (N = 22; Mean age = 6.26 years, SD = 0.82). There was a significant positive correlation between verbal mental age and shift percentage for children with ASD. Group differences on the FIST converge and extend prior evidence documenting an impaired ability to adapt rapidly to changes in task demands for individuals with ASD. Keywords Cognitive flexibility * Autism spectrum disorders * Set-shifting * Executive function * Cognitive control, Cognitive flexibility is the process of adapting thoughts and behavior in response to situational demands (Geurts et al. 2009). Cognitive flexibility is impaired in adults and children with autism spectrum [...]

To test the relation between sluggish cognitive tempo (SCT) and DSM-IV ADHD symptoms, parent and teacher ratings of the 18 DSM-IV ADHD items and five potential SCT items were obtained in a community sample of 8-18 year-old twins that was overselected for ADHD and learning disabilities (n = 296). Confirmatory factor analyses revealed that a three-factor model provided the best fit to the data for both parent and teacher ratings. DSM-IV inattention and hyperactivity-impulsivity symptoms loaded on two factors consistent with the DSM-IV model, and five SCT symptoms loaded primarily on a third factor. The SCT and inattention factors were highly correlated, whereas SCT and hyperactivity-impulsivity were weakly related. Both raters indicated that children meeting symptom criteria for the combined and inattentive subtypes exhibited significantly more SCT symptoms than those meeting symptom criteria for hyperactive-impulsive type and the comparison group without ADHD. Children meeting symptom criteria for the inattentive type exhibited significantly more SCT symptoms than those meeting criteria for the combined type, based on teacher ratings. These results suggest that SCT is an internally consistent construct that is significantly associated with DSM-IV inattention. KEY WORDS: attention-deficit/hyperactivity disorder; DSM-IV; subtypes; factor analysis; sluggish cognitive tempo.

Byline: Sally Ozonoff (1,9), Ian Cook (9), Hilary Coon (1), Geraldine Dawson (2), Robert M. Joseph (3), Ami Klin (4), William M. McMahon (1), Nancy Minshew (5), Jeffrey A. Munson (2), Bruce F. Pennington (6), Sally J. Rogers (7,9), M. Anne Spence (8), Helen Tager-Flusberg (3), Fred R. Volkmar (4), Debora Wrathall (1) Keywords: Autism; executive function; planning; set shifting; frontal lobes; CANTAB Abstract: Recent structural and functional imaging work, as well as neuropathology and neuropsychology studies, provide strong empirical support for the involvement of frontal cortex in autism. The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a computer-administered set of neuropsychological tests developed to examine specific components of cognition. Previous studies document the role of frontal cortex in performance of two CANTAB subtests: the Stockings of Cambridge, a planning task, and the Intradimensional/Extradimensional Shift task, a measure of cognitive set shifting. To examine the integrity of frontal functions, these subtests were administered to 79 participants with autism and 70 typical controls recruited from seven universities who are part of the Collaborative Programs of Excellence in Autism network. The two groups were matched on age, sex, and full-scale IQ. Significant group differences were found in performance on both subtests, with the autism group showing deficits in planning efficiency and extradimensional shifting relative to controls. Deficits were found in both lower- and higher-IQ individuals with autism across the age range of 6 to 47 years. Impairment on the CANTAB executive function subtests did not predict autism severity or specific autism symptoms (as measured by the ADI-R and ADOS), but it was correlated with adaptive behavior. If these CANTAB subtests do indeed measure prefrontal function, as suggested by previous research with animals and lesion patients, this adds to the accumulating evidence of frontal involvement in autism and indicates that this brain region should remain an active area of investigation. Author Affiliation: (1) Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah (2) Center on Human Development and Disability, University of Washington, Seattle, Washington (3) Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts (4) Child Study Center, Yale University School of Medicine, New Haven, Connecticut (5) Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (6) Department of Psychology, University of Denver, Denver, Colorado (7) Department of Psychiatry, University of Colorado Health Sciences Center, Denver, Colorado (8) Department of Pediatrics, University of California--Irvine, Irvine, California (9) M.I.N.D. Institute, University of California--Davis School of Medicine, Sacramento, California Article History: Registration Date: 18/10/2004

Byline: Dianne L. Koczat (1), Sally J. Rogers (1), Bruce F. Pennington (2), Randal G. Ross (1,3) Keywords: Endophenotype; saccade; autism Abstract: Autistic probands exhibit impaired spatial accuracy and impaired response suppression errors during a delayed oculomotor response task. Family members of autistic probands, and thus the possible familial nature of these deficits, have not been assessed. Eleven parents of autistic probands and 17 adults from unaffected families, ages 25--50 years, completed oculomotor delayed-response tasks. Parents of autistic probands demonstrated poorer spatial accuracy than the comparison group (p = .002), with no significant differences between groups on percentage of premature saccades or latency of remembered saccades. Spatial working memory deficits, as measured by the delayed oculomotor response task, appear to be familial in families with an autistic proband. These deficits deserve further evaluation as a potential endophenotypic marker for genetic risk for autism. Author Affiliation: (1) Department of Psychiatry, University of Colorado Health Sciences Center, Denver, Colorado (2) Department of Psychology, University of Denver, Denver, Colorado (3) Department of Psychiatry, Denver Veterans Administration Medical Center, Denver, Colorado Article History: Registration Date: 12/10/2004

Byline: Malinda Carpenter (1), Bruce F. Pennington (2), Sally J. Rogers (3) Keywords: Autism; joint attention; imitation; gestural communication; point and gaze following; language Abstract: Typically developing infants show a reliable developmental sequence of emergence of early social-cognitive skills, such as joint attention, communicative gestures, gaze and point following, imitation, and referential language. First infants share others' attention, then they follow others' attention and then behavior, and then they direct others' attention and then behavior. The current study used a series of tests from a study of typically developing infants (Carpenter, Nagell, &amp Tomasello, 1998) to investigate interrelations among these social-cognitive skills in young children with autism and children with other developmental delays. Tests of object permanence, spatial relations, facial and manual imitation, and executive function also were included. We found that for most children with autism, unlike other children, tests involving others' attention were more difficult than tests involving others' behavior. However, within the domains of attention and behavior, the typical pattern of sharing, then following, and then directing was evident. There were several positive intercorrelations among the social-cognitive skills (as there were for typically developing infants), but there also was some evidence of individual differences in patterns. Implications for theories of social-cognitive and language development are discussed. Author Affiliation: (1) Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany (2) Department of Psychology, University of Denver, Denver, Colorado, 80208 (3) Health Sciences Center, University of Colorado, Denver, Colorado, 80262 Article History: Registration Date: 30/09/2004

Byline: Malinda Carpenter (1), Bruce F. Pennington (2), Sally J. Rogers (3) Keywords: Intention; imitation; theory of mind; joint attention Abstract: Many studies have shown that children with autism have difficulty understanding the thoughts and beliefs of other people. However, little research has been conducted on what these children understand about simpler mental states such as intentions. The current study tested the understanding of others' intentions in 2 1/2- to 5-year-old children with autism and a control group of children with other developmental delays. We used Meltzoff's (1995) test of understanding of others' unfulfilled intentions in an imitation context, with an additional 'End State' condition. We found no significant between-group differences on any measure involving the understanding of others' intentions. Although within-group patterns suggested that children with autism may have a slightly less complex understanding of others' intentions than do other children, it was clear that any deficits these children showed in this area were not as marked as those they typically show on traditional theory of mind tasks. Author Affiliation: (1) Max Planck Institute for Evolutionary Anthropology, USA (2) University of Denver, USA (3) University of Colorado Health Sciences Center, USA Article History: Registration Date: 16/10/2004

A twin study of attention deficit hyperactivity disorder (ADHD) provided evidence supporting a genetic etiology of the disorder. Multiple regression analysis was applied to data from a subset of reading-disabled twins. The sample included 37 identical and 37 fraternal twin pairs. At least one twin in each pair had attention deficit disorder according to the Diagnostic Interview for Children and Adolescents. Statistical analysis of the data produced a substantial value for hereditary influence on ADHD.

Studies of subtypes of DSM-IV attention-deficit/hyperactivity disorder (ADHD) have provided inconsistent support for the discriminant validity of the combined type (ADHD-C) and predominantly inattentive type (ADHD-I). A large sample of children and adolescents with ADHD (N = 410) and a comparison group without ADHD (N = 311) were used to test the internal and external validity of sluggish cognitive tempo (SCT), a dimension characterized by low energy and sleepy and sluggish behavior. SCT scores were then incorporated in analyses of ADHD subtypes to test whether the discriminant validity of ADHD-C and ADHD-I could be improved by including SCT symptoms as part of the criteria for ADHD-I. Factor analyses of parent and teacher ratings indicated that six SCT items loaded on a factor separate from symptoms of ADHD and other psychopathology, providing important support for the internal validity of SCT. The external validity of SCT was supported by significant associations between SCT and measures of functional impairment and neuropsychological functioning when symptoms of ADHD and other psychopathology were controlled. However, contrary to initial predictions, high levels of SCT did not identify a subgroup of ADHD-I that was clearly distinct from ADHD-C. Instead, the current results suggest that DSM-IV inattention and SCT are separate but correlated symptom dimensions that are each independently associated with important aspects of functional impairment and neuropsychological functioning.

We examined reading comprehension in children with ADHD by assessing their ability to build a coherent mental representation that allows them to recall central and peripheral information. We compared children with ADHD (mean age 9.78) to word reading-matched controls (mean age 9.89) on their ability to retell a passage. We found that even though children with ADHD recalled more central than peripheral information, they showed their greatest deficit, relative to controls, on central information-a centrality deficit (Miller and Keenan, Annals of Dyslexia 59:99-113, 2009). We explored the cognitive underpinnings of this deficit using regressions to compare how well cognitive factors (working memory, inhibition, processing speed, and IQ) predicted the ability to recall central information, after controlling for word reading ability, and whether these cognitive factors interacted with ADHD symptoms. Working memory accounted for the most unique variance. Although previous evidence for reading comprehension difficulties in children with ADHD have been mixed, this study suggests that even when word reading ability is controlled, children with ADHD have difficulty building a coherent mental representation, and this difficulty is likely related to deficits in working memory.

Although previous research has identified contemporaneous associations between cognitive deficits and symptom phenotypes in Attention Deficit/Hyperactivity Disorder, no studies have as yet attempted to identify direction of effect. The present study used cross-lagged path modeling to examine competing hypotheses about longitudinal associations between rapid naming speed and symptoms of inattention in children. 1,506 school-age twins from Australia and the U.S. were tested for inattention, hyperactivity/impulsivity, and rapid naming speed at three and four time points, respectively. Symptom severity of inattention from Kindergarten to fourth grade is consistently predicted by previous rapid naming, over and above auto-regressive and correlational associations in the model. Likewise, inattention symptoms have a small but significant predictive effect on subsequent rapid naming. The findings support a reciprocal relationship between naming speed and ADHD inattentive symptoms.

This study focuses on the comorbidity between attention-deficit/hyperactivity disorder (ADHD) symptoms and speech sound disorder (SSD). SSD is a developmental disorder characterized by speech production errors that impact intelligibility. Previous research addressing this comorbidity has typically used heterogeneous groups of speech-language disordered children. This study employed more precise speech-language diagnostic criteria and examined ADHD symptomatology in 108 SSD children between the ages of 4 and 7 years old with specific language impairment (SLI) (n = 23, 14 males, 9 females) and without SLI (n = 85, 49 males, 36 females). We also examined whether a subcategory of SSD, persistent (n = 39, 25 males, 14 females) versus normalized SSD (n = 67, 38 males, 29 females), was associated with ADHD and/or interacted with SLI to predict ADHD symptomatology. Results indicated that participants in the SSD + SLI group had higher rates of inattentive ADHD symptoms than those in the SSD-only and control groups. In addition, an unexpected interaction emerged such that children with SLI and normalized-SSD had significantly higher ADHD inattentive ratings than the other subgroups. A proposed explanation for this interaction is discussed.

There is significant comorbidity between attention-deficit/hyperactivity disorder (ADHD) and conduct disorder (CD). The conclusions of studies that examined the causes of comorbidity between ADHD and CD conflict, with some researchers finding support for the three independent disorders model and others finding support for the correlated risk factors model. We tested these models and eleven alternative hypotheses using the same analytical approach. The participants were 110 monozygotic twin pairs and 181 dizygotic twin pairs recruited from the Colorado Learning Disabilities Research Center Twin Study. The three independent disorders model did not fit the data, whereas the correlated risk factors model fit the data well. Several other comorbidity models fit the data as well as or better than the correlated risk factors model. The results suggest that correlated risk factors are a better explanation for the comorbidity between ADHD and CD than a third, independent ADHD+CD subtype.

The present study is the first to utilize twin modeling to examine whether parent-teacher disagreement for ADHD ratings is due to parent or teacher bias, or due to raters observing different but valid ADHD behaviors. A joint analysis was conducted with 106 twin pairs, including twins selected for ADHD and control twin pairs. Total ADHD scores were analyzed using multiple rater models that estimate genetic and environmental contributions common to both raters and unique to each rater. Results suggest that 1) disagreement in ADHD ratings is strongly due to parents and teachers observing different ADHD behaviors, some of which is valid and some of which is due to bias, and 2) parents may be more biased than teachers in their ADHD ratings.

Recent research on executive function (EF) deficits in autism has led investigators to conclude that EF deficits are secondary to the disorder. The current study has two major goals: (1) Examine whether specific EF deficits are present in the youngest autism group to date (mean=2.9 years), and (2) examine whether such deficits are secondary to autism, or act as an early non-specific cognitive risk factor for autism by comparing EF abilities of this autism group to a CA-matched typically developing group. Results from Experiment 1 suggest no specific EF deficits in autism relative to MA-matched controls, while results from Experiment 2 are consistent with the hypothesis that EF deficits may emerge as a secondary deficit in autism. Alternative hypotheses are also considered.

Visual perception may be a developmental prerequisite to some types of social understanding. The ability to perceive social information given visual motion appears to develop early. However, children with autism have profound deficits in social cognitive function and may fail to see social motion in the same way that typically developing children do. We tested the hypothesis that children with autism fail to discriminate animate motion, using a novel paradigm involving simple geometric figures. The subjects were 23 children with autism (c.a. 70.7 mos.), 18 children with other developmental disabilities (c.a. 68.2 mos.), and 18 typically developing children (c.a. 46.4 mos.). Children saw two circles moving on a screen and were rewarded for identifying the one that moved as if animate. A control condition required children to identify the heavier of two objects. Children with autism initially showed a deficit in categorizing objects as animate (though no deficit on the control task), but showed no deficit in this ability after they had reached criterion in the training phase. These results are discussed in terms of the social orienting theory of autism, and the possibility that animacy perception might be preserved in autism, even if it is not used automatically.

The goal of the current study was to test whether deficits in processing speed (PS) may be a shared cognitive risk factor in reading disability (RD) and Attention Deficit/Hyperactivity Disorder (ADHD), which are known to be comorbid. Literature on ADHD and RD suggests that deficits on tasks with a speeded component are seen in both of these disorders individually. The current study examined a wide range of speeded tasks in RD, ADHD, comorbid RD+ADHD, and a control group to test whether RD and ADHD have similar profiles of PS deficits, and whether these deficits are shared by the two disorders. The results suggest that a general PS deficit exists in both clinical groups compared to controls, although children with RD demonstrate greater PS deficits than children with ADHD. Two tests (underadditivity and partial correlations) were conducted to test whether these PS deficits are shared. Since we found that PS deficits were underadditive in the comorbid group and that partialling PS reduced the correlation between RD and ADHD, it appears that PS is a shared cognitive risk factor that may help explain the comorbidity of these two disorders.

The profile of spatial ability is of interest across autism spectrum disorders (ASD) because of reported spatial strengths in ASD and due to the recent association of Asperger's syndrome with Nonverbal Learning Disability. Spatial functions were examined in relation to two cognitive theories in autism: the central coherence and executive function (EF) theories. Performance on spatial tasks, EFs, and global/local processing was compared in children with ASD and controls. While the ASD group had faster reaction times on the Embedded Figures task, spatial performance was intact, but not superior, on other tasks. There was no evidence for impairments in EF or in processing global/local information, therefore contradicting these two theories. The implications of these results for these two theories are discussed.