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Biomedical subjects

S Ozonoff

Publications and source records attributed to S Ozonoff.

At least 19 recordsLinked to original sources
PubMed2001

Further evidence of intact working memory in autism.

Earlier investigations have found mixed evidence of working memory impairment in autism. The present study examined working memory in a high-functioning autistic sample, relative to both a clinical control group diagnosed with Tourette Syndrome and a typically developing control group. No group differences were found across three tasks and five dependent measures of working memory. Performance was significantly correlated with both age and IQ. It is concluded that working memory is not one of the executive functions that is seriously impaired in autism. We also suggest that the format of administration of working memory tasks may be important in determining whether or not performance falls in the impaired range.

Adolescent↗
PubMed2001

Double-blind, placebo-controlled study of amantadine hydrochloride in the treatment of children with autistic disorder.

OBJECTIVE: To test the hypothesis that amantadine hydrochloride is a safe and effective treatment for behavioral disturbances--for example, hyperactivity and irritability--in children with autism. METHOD: Thirty-nine subjects (intent to treat; 5-19 years old; IQ > 35) had autism diagnosed according to DSM-IV and ICD-10 criteria using the Autism Diagnostic Interview-Revised and the Autism Diagnostic Observation Schedule-Generic. The Aberrant Behavior Checklist-Community Version (ABC-CV) and Clinical Global Impressions (CGI) scale were used as outcome variables. After a 1-week, single-blind placebo run-in, patients received a single daily dose of amantadine (2.5 mg/kg per day) or placebo for the next week, and then bid dosing (5.0 mg/kg per day) for the subsequent 3 weeks. RESULTS: When assessed on the basis of parent-rated ABC-CV ratings of irritability and hyperactivity, the mean placebo response rate was 37% versus amantadine at 47% (not significant). However, in the amantadine-treated group there were statistically significant improvements in absolute changes in clinician-rated ABC-CVs for hyperactivity (amantadine -6.4 versus placebo -2.1; p = .046) and inappropriate speech (-1.9 versus 0.4; p = .008). CGI scale ratings were higher in the amantadine group: 53% improved versus 25% (p = .076). Amantadine was well tolerated. CONCLUSIONS: Parents did not report statistically significant behavioral change with amantadine. However, clinician-rated improvements in behavioral ratings following treatment with amantadine suggest that further studies with this or other drugs acting on the glutamatergic system are warranted. The design of these and similar drug trials in children with autistic disorder must take into account the possibility of a large placebo response.

Adolescent↗
PubMed2001

Multisite, double-blind, placebo-controlled trial of porcine secretin in autism.

OBJECTIVE: To examine the efficacy of intravenous porcine secretin for the treatment of autistic disorder. METHOD: Randomized, double-blind, placebo-controlled, crossover design. Fifty-six subjects with autistic disorder received either a secretin or placebo infusion at baseline and the other substance at week 4. Subjects were given the Autism Diagnostic Observation Schedule (ADOS) and other pertinent developmental measures at baseline and at weeks 4 and 8 to assess drug effects. RESULTS: For the primary efficacy analysis, change of ADOS social-communication total score from week 0 to week 4, no statistically significant difference was obtained between placebo (-0.8 +/- 2.9) and secretin groups (-0.6 +/- 1.4; t54 = 0.346, p < .73). The other measures showed no treatment effect for secretin compared with placebo. CONCLUSION: There was no evidence for efficacy of secretin in this randomized, placebo-controlled, double-blind trial.

Autistic Disorder↗
PubMed2000

Practice parameter: screening and diagnosis of autism: report of the Quality Standards Subcommittee of the American Academy of Neurology and the Child Neurology Society [RETIRED].

Autism is a common disorder of childhood, affecting 1 in 500 children. Yet, it often remains unrecognized and undiagnosed until or after late preschool age because appropriate tools for routine developmental screening and screening specifically for autism have not been available. Early identification of children with autism and intensive, early intervention during the toddler and preschool years improves outcome for most young children with autism. This practice parameter reviews the available empirical evidence and gives specific recommendations for the identification of children with autism. This approach requires a dual process: 1) routine developmental surveillance and screening specifically for autism to be performed on all children to first identify those at risk for any type of atypical development, and to identify those specifically at risk for autism; and 2) to diagnose and evaluate autism, to differentiate autism from other developmental disorders.

Asperger Syndrome↗
PubMed2000

Behavior phenotype of FG syndrome: cognition, personality, and behavior in eleven affected boys.

In this study we examined several behavioral, personality, and cognitive characteristics of boys with FG syndrome. We confirmed high rates of attention and activity level problems, which were described previously. Nine of the 11 patients met criteria for attention deficit/hyperactivity disorder. The boys did not manifest autistic behavior, and none met criteria for an autism spectrum disorder, though their parents reported substantial repetitive behavior. The personalities of the participants often were described as friendly, good-natured, and cheerful, but they did not differ empirically on a standardized measure of personality structure from typically developing comparison children, even after controlling for the effects of IQ. Specifically, higher rates of agreeableness and extraversion were not confirmed, though these constructs do not correspond perfectly with the traits of affability and gregariousness described in earlier published case studies of FG syndrome. In terms of neuropsychological assessment, the boys had relatively less developed language, fine motor, and executive function skills, and visual-spatial abilities were a relative strength. Limitations and suggestions for future research are discussed.

Adolescent↗
PubMed2000

The external validity of Asperger disorder: lack of evidence from the domain of neuropsychology.

The present study compared individuals with high-functioning autism (HFA) and Asperger disorder (AD) in intellectual, motor, visuospatial, and executive function domains. Participants with AD demonstrated significantly higher Verbal and Full Scale IQ scores, significantly larger Verbal-Performance IQ discrepancies, and significantly better visual-perceptual skills than those with HFA. Once the superior intellectual abilities of the AD group were controlled (both statistically through analysis of covariance and by examining IQ-matched subgroups of HFA and AD participants), no significant group differences in motor, visuospatial, or executive functions were evident, save a marginally significant trend toward poorer fine motor performance in the AD group. This suggests that AD may simply be "high-IQ autism" and that separate names for the disorders may not be warranted. The relation of these findings to theories of autism and AD are discussed.

Asperger Syndrome↗
PubMed1999

Cognitive impairment in neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is associated with a broad range of relatively nonspecific cognitive impairments, including low IQ, learning disabilities, and behavioral difficulties. While early studies indicated that the cognitive phenotype of NF1 resembles that of nonverbal learning disabilities (NLD), later research has found that the impairments are broader and do not fit the NLD profile well. Language-based deficits and executive dysfunction have also been found in empirical studies. There is some evidence that neuropsychological impairment may be correlated with the underlying central nervous system involvement of NF1, but this theory has not been consistently supported across studies. Further work clarifying the cognitive phenotype of NF1 is needed, especially investigations that employ appropriate comparison groups matched for intellectual level. Am. J. Med. Genet. (Semin. Med. Genet.) 89:45-52, 1999.

Cognition Disorders↗
PubMed1999

The screening and diagnosis of autistic spectrum disorders.

The Child Neurology Society and American Academy of Neurology recently proposed to formulate Practice Parameters for the Diagnosis and Evaluation of Autism for their memberships. This endeavor was expanded to include representatives from nine professional organizations and four parent organizations, with liaisons from the National Institutes of Health. This document was written by this multidisciplinary Consensus Panel after systematic analysis of over 2,500 relevant scientific articles in the literature. The Panel concluded that appropriate diagnosis of autism requires a dual-level approach: (a) routine developmental surveillance, and (b) diagnosis and evaluation of autism. Specific detailed recommendations for each level have been established in this document, which are intended to improve the rate of early suspicion and diagnosis of, and therefore early intervention for, autism.

Asperger Syndrome↗
PubMed1999

Autism and autistic behavior in Joubert syndrome.

To determine whether individuals with Joubert syndrome exhibit features of autism as defined by the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV), we examined 11 children with Joubert syndrome using the Autism Diagnostic Interview-Revised and the Autism Diagnostic Observation Schedule-Generic. Three children met DSM-IV criteria for autistic disorder and one for pervasive developmental disorder not otherwise specified. The other seven all demonstrated at least one DSM-IV symptom of autism, but did not meet criteria for a pervasive developmental disorder. Both total number of DSM-IV symptoms and number of social symptoms distinguished the autism and nonautism subgroups. In contrast, the two subgroups displayed similar levels of communication impairments and repetitive or stereotyped behavior. The key to diagnosing autism in Joubert syndrome is to focus on social behaviors, particularly milestones typically achieved very early in life (eg, attending to human voices, showing objects of interest, enjoyment of social interactions). Implications for the role of the cerebellum in nonmotor behavior and for clinical management of Joubert syndrome also are discussed.

Adolescent↗
PubMed1998

Effectiveness of a home program intervention for young children with autism.

This project evaluated the effectiveness of a TEACCH-based home program intervention for young children with autism. Parents were taught how to work with their preschool autistic child in the home setting, focusing on cognitive, academic, and prevocational skills essential to later school success. To evaluate the efficacy of the program, two matched groups of children were compared, a treatment group and a no-treatment control group, each consisting of 11 subjects. The treatment group was provided with approximately 4 months of home programming and was tested before and after the intervention with the Psychoeducational Profile-Revised (PEP-R). The control group did not receive the treatment but was tested at the same 4-month interval. The groups were matched on age, pretest PEP-R scores, severity of autism, and time to follow-up. Results demonstrated that children in the treatment group improved significantly more than those in the control group on the PEP-R subtests of imitation, fine motor, gross motor, and nonverbal conceptual skills, as well as in overall PEP-R scores. Progress in the treatment group was three to four times greater than that in the control group on all outcome tests. This suggests that the home program intervention was effective in enhancing development in young children with autism.

Achievement↗
PubMed1998

Inhibitory deficits in Tourette syndrome: a function of comorbidity and symptom severity.

This study examined central inhibitory function in children with Tourette syndrome (TS; N = 46) and normally developing controls (N = 22) matched on age, gender, and IQ. A negative priming task measured the ability to inhibit processing of irrelevant distractor stimuli presented on a visual display. Initial analyses indicated that participants with Tourette syndrome did not differ significantly in inhibitory function from controls. However, when the large Tourette syndrome sample was separated into subgroups, one without evidence of comorbidity (N = 23) and the other meeting research criteria for either AD/HD, OCD, or both (N = 23), it became evident that individuals with Tourette syndrome with comorbid conditions tended to perform less well than the control group, whereas those without comorbidity performed much like controls. Similarly, when the large Tourette syndrome sample was divided into two subgroups on the basis of severity of symptomatology (N = 23 in each), those with more numerous and severe symptoms of Tourette syndrome, AD/HD, and OCD performed significantly less well than both controls and Tourette syndrome subjects with fewer and less severe symptoms. This suggests that neuropsychological impairment occurs as a function of comorbidity and symptom severity in Tourette syndrome. It also suggests that categorical diagnoses alone may be less useful than dimensional methods for predicting cognitive impairment in individuals with Tourette syndrome.

Adolescent↗
PubMed1997

Inhibitory function in nonretarded children with autism.

This study examined inhibitory function in nonretarded children with autism (n = 13) and normally developing controls (n = 13) matched on age and IQ. Tasks measuring motor and cognitive components of inhibition were administered to both groups. On the Stop-Signal paradigm, children with autism were able to inhibit motor responses to neutral and prepotent stimuli as well as control subjects. On the Negative Priming task, the groups were equally capable of inhibiting processing of irrelevant distractor stimuli in a visual display. Results suggest that at least two components of inhibition are spared in individuals with autism, standing in contrast to flexibility and other executive deficits that have been found in previous studies. These findings may help distinguish children with autism from those with other neurodevelopmental conditions that involve executive dysfunction.

Adolescent↗
PubMed1997

Did Asperger's cases have Asperger disorder? A research note.

With publication of the fourth edition of the Diagnostic and statistical manual of mental disorders (DSM-IV), standardized criteria for Asperger Disorder, a putative subtype of Pervasive Developmental Disorder, are now available. This paper examines the four cases Asperger originally presented in his seminal paper (1991/1994), using DSM-IV criteria to determine whether a diagnosis of Autistic or Asperger Disorder is most appropriate. We found that all four cases met DSM-IV criteria for Autistic Disorder, rather than Asperger Disorder. This suggests that the syndrome Asperger originally described may not be captured by present diagnostic criteria. Implications for future research are discussed.

Autistic Disorder↗
PubMed1996

An exploration of right-hemisphere contributions to the pragmatic impairments of autism.

This study examined the potential contribution of the right hemisphere to the communicative impairments of autism. Pragmatic language measures sensitive to right-hemisphere damage were administered to nonretarded adults with autism and to controls matched on age and intellectual ability. The experimental battery included measures of humor, inference, and indirect request comprehension. Autistic subjects performed significantly less well than controls on all measures, replicating results of an earlier investigation by Rumsey and Hanahan (Journal of Clinical and Experimental Neuropsychology, 12, 81, 1990). The performance of the autistic group on the three tasks was also similar to that of right-hemisphere stroke patients reported previously (Molloy, Brownell, & Gardner, in Y. Joanette and H. M. Brownell (Eds.), Discourse ability and brain damage: Theoretical and empirical perspectives, New York: Springer-Verlag, 1990,pp. 113-130). Generalizability of these results and implications for the neuropathology of autism are discussed.

Adolescent↗
PubMed1996

Executive functions and developmental psychopathology.

In this paper, we consider the domain of executive functions (EFs) and their possible role in developmental psychopathologies. We first consider general theoretical and measurement issues involved in studying EFs and then review studies of EFs in four developmental psychopathologies: attention deficit hyperactivity disorder (ADHD), conduct disorder (CD), autism, and Tourette syndrome (TS). Our review reveals that EF deficits are consistently found in both ADHD and autism but not in CD (without ADHD) or in TS. Moreover, both the severity and profile of EF deficits appears to differ across ADHD and autism. Molar EF deficits are more severe in the latter than the former. In the few studies of more specific EF tasks, there are impairments in motor inhibition in ADHD but not in autism, whereas there are impairments in verbal working memory in autism but not ADHD. We close with a discussion of implications for future research.

Adolescent↗
PubMed1995

Teaching theory of mind: a new approach to social skills training for individuals with autism.

This study examined the effectiveness of a social skills training program for normal-IQ adolescents with autism. Five boys participated in the 4 1/2-month treatment condition; four boys matched on age, IQ, and severity of autism constituted the no-treatment control group. In addition to teaching specific interactional and conversational skills, the training program provided explicit and systematic instruction in the underlying social-cognitive principles necessary to infer the mental states of others (i.e., theory of mind). Pre- and post-intervention assessment demonstrated meaningful change in the treatment group's performance on several false belief tasks, but no improvement in the control sample. No changes, however, were demonstrated on general parent and teacher ratings of social competence for either group.

Adolescent↗
PubMed1994

Executive function abilities in autism and Tourette syndrome: an information processing approach.

This study used information processing paradigms to provide a detailed examination of executive function abilities in autism. The performance of non-retarded autistic children was compared with that of two matched control groups, one with Tourette Syndrome and the other developmentally normal. Autistic subjects performed as well as controls on tasks requiring global-local processing and inhibition of neutral responses. In contrast to both control groups, however, the autistic sample was significantly impaired on a measure of cognitive flexibility. The performance of children with Tourette Syndrome did not differ from that of normal controls on any task. These results refine our knowledge about executive dysfunction in autism and suggest a new conceptual framework and general method for investigating the cognitive underpinnings of neurodevelopmental disorders.

Adolescent↗