Haruhisa Ota

Deficit in visual temporal integration in autism spectrum disorders

Individuals with autism spectrum disorders (ASD) are superior in processing local features. Frith and Happe conceptualize this cognitive bias as ‘weak central coherence’, implying that a local enhancement derives from a weakness in integrating local elements into a coherent whole. The suggested deficit has been challenged, however, because individuals with ASD were not found to be inferior to normal controls in holistic perception. In these opposing studies, however, subjects were encouraged to ignore local features and attend to the whole. Therefore, no one has directly tested whether individuals with ASD are able to integrate local elements over time into a whole image. Here, we report a weakness of individuals with ASD in naming familiar objects moved behind a narrow slit, which was worsened by the absence of local salient features. The results indicate that individuals with ASD have a clear deficit in integrating local visual information over time into a global whole, providing direct evidence for the weak central coherence hypothesis.

Clinical and psychosocial characteristics in adults with pervasive development disorders: a survey in Japan

Abstract Background: In spite of the relatively high prevalence of pervasive development disorders (PDD), the medical and educational services for persons with PDD are insufficient in Japan. The present study investigated the clinical and psychosocial characteristics of adults with PDD in Japan. Methods: We selected 111 individuals with PDD out of the 257 subjects attending an outpatient clinic for adult PDD at Showa University Karasuyama Hospital, between the period of July 2008 and June of 2009. Sociodemographic factors, psychosocial characteristics, and medication status of the subjects were investigated. Results: The mean age of subjects at the initial visit to a medical organization was 21.4 years; however, only 34.2% were diagnosed as having PDD. These results indicated that persons with PDD are apt to be misdiagnosed. Most of the persons with PDD were unmarried, and lived with their parents. This may be partly due to economic reasons, because the unemployment rate was high in this group. More than 45% of the subjects with PDD were taking psychoactive medications, which indicated that they carried a high-risk for co-existing mental health problems. Conclusions: The results of the present study indicated that many persons with PDD are socially isolated, in spite of their relatively high level of education, and that these individuals require additional medical and educational services.

P300 component of event-related potentials in persons with asperger disorder

Summary: In the present study, we investigated auditory event-related potentials in adults with Asperger disorder and normal controls using an auditory oddball task and a novelty oddball task. Task performance and the latencies of P300 evoked by both target and novel stimuli in the two tasks did not differ between the two groups. Analysis of variance revealed that there was a significant interaction effect between group and electrode site on the mean amplitude of the P300 evoked by novel stimuli, which indicated that there was an altered distribution of the P300 in persons with Asperger disorder. In contrast, there was no significant interaction effect on the mean P300 amplitude elicited by target stimuli. Considering that P300 comprises two main subcomponents, frontal-central-dominant P3a and parietal-dominant P3b, our results suggested that persons with Asperger disorder have enhanced amplitude of P3a, which indicated activated prefrontal function in this task.

Cognitive profiles of adults with high-functioning autism spectrum disorder and those with attention-deficit/hyperactivity disorder based on the WAIS-III.

The cognitive profile differences between adult patients with autism spectrum disorder (ASD) and those with attention-deficit/hyperactivity disorder (ADHD) are not well characterized. We examined the cognitive profiles of adults having either ASD (n=120) or ADHD (n=76) with no intellectual disabilities (IQ≥70) using the Wechsler Intelligence Scale III (WAIS-III). Verbal Intelligence (VIQ) - Performance Intelligence (PIQ) difference discrepancies were detected between the two groups. Information subtest scores of the Verbal Comprehension index and Arithmetic and Digit Span subtests of the Freedom from Distractibility index were significantly higher in ASD than in ADHD, while the Picture Completion subtest was significantly lower in ASD. To our knowledge, this is the first study to evaluate the difference in the cognitive profiles of adults with ASD and those with ADHD based on the WAIS III with a large number of participants.