Luke Y. Tsai

Morphological evidence for brainstem involvement in infantile autism

Previous neurophysiological and neuroanatomic studies suggest brainstem dysfunction in infantile autism. Therefore, we investigated the brainstem structure of autistic patients by planimetric analysis of midsagittal magnetic resonance imaging scans. We found the entire brainstem and one component--the pons--to be statistically significantly smaller in the autistic group when compared with medical controls. We also noted no correlation between brainstem size and age in the autistic group--a correlation that was found in the control group. These data present morphological evidence of brainstem involvement in the infantile autism syndrome.

Forebrain Structure in Infantile Autism

Researchers implicate central nervous system dysfunction in infantile autism, but postmortem examinations and in vivo brain imaging studies have produced conflicting results concerning the neuronal systems involved. Magnetic resonance imaging--a new modality of in vivo brain imaging--was used to investigate the cerebral and thalamic structure of 105 autistic patients. Compared with the control group, there was an overall difference in the forebrain morphology of the autistic subjects due to subtle but statistically significant differences in the anterior ventricular horns, lateral ventricles, and the right lenticular nucleus. These results, when considered with previous studies of cerebral structure, suggest that there are subtle alterations in the forebrain of autistic patients.

Serotonin Relationships of Autistic Probands and Their First-Degree Relatives

Thirty autistic children and 84 of their first-degree relatives were examined for serotonin blood levels and platelet counts. Among the autistic children, boys have higher serotonin blood levels than girls. Furthermore, autistic boys have higher levels than fathers, but have levels resembling those of their siblings. Autistic girls have lower blood serotonin levels than male siblings. Despite these differences, autistic children and their families have a strong familial resemblance when serotonin blood levels are adjusted for age, sex, and platelet counts.

Brief report: Thought disorder in asperger syndrome: Comparison with high-functioning autism

Asperger syndrome (AS) is a pervasive developmental disorder generally regarded as a variant of autism. While it has been included in the ICD-10 and DSM-IV as a distinct diagnostic entity, it is still unclear to what extent it differs from highfunctioning autism (HFA). Persons with HFA have been reported to show a variety of deficits of thought processes. Abnormalities such as poor reality testing, perceptual distortions, and areas of cognitive slippage have been described using the Rorschach inkblot test (Dykens, Volkmar, & Glick, 1991). Since AS has been conceptualized as a mild variant of autism, we hypothesized that persons with AS will have fewer abnormalities on the Rorschach test compared to persons with HFA. To test this hypothesis, we compared 12 subjects with AS (ICD-10, 10 male, mean age = 12.2±3.3 years, mean full-scale IQ = 99.6) with 8 subjects with HFA (ICD-10/DSM-III-R, 7 male, mean age = 12.2±3.8 years, mean fullscale IQ = 83.4) on the Rorschach test. AS subjects demonstrated a trend towards greater levels of disorganized thinking than the HFA group. They were also more likely to be classified as “Introversive” suggesting that AS subjects may have more complex inner lives involving elaborate fantasies. Also, AS subjects tended to be more focused on their internal experiences. However, overall, the Rorschach test was not found to differentiate the two diagnostic groups on the majority of structural variables. Implications of these findings are discussed with regard to the diagnostic validity of Asperger syndrome.

DSM-5 ASD Moves Forward into the Past

The fifth edition of the diagnostic and statistical manual of mental disorders (DSM-5) (APA in diagnostic and statistical manual of mental disorders, Author, Washington, 2013) has decided to merge the subtypes of pervasive developmental disorders into a single category of autism spectrum disorder (ASD) on the assumption that they cannot be reliably differentiated from one another. The purpose of this review is to analyze the basis of this assumption by examining the comparative studies between Asperger’s disorder (AsD) and autistic disorder (AD), and between pervasive developmental disorder not otherwise specified (PDDNOS) and AD. In all, 125 studies compared AsD with AD. Of these, 30 studies concluded that AsD and AD were similar conditions while 95 studies found quantitative and qualitative differences between them. Likewise, 37 studies compared PDDNOS with AD. Nine of these concluded that PDDNOS did not differ significantly from AD while 28 reported quantitative and qualitative differences between them. Taken together, these findings do not support the conceptualization of AD, AsD and PDDNOS as a single category of ASD. Irrespective of the changes proposed by the DSM-5, future research and clinical practice will continue to find ways to meaningfully subtype the ASD.

Asperger’s Disorder will be Back

This review focuses on identifying up-to-date number of publications that compared DSM-IV/ICD-10 Asperger’s disorder (AspD) to Autistic Disorder/High-functioning Autism (AD/HFA). One hundred and twenty-eight publications were identified through an extensive search of major electronic databases and journals. Based on more than 90 clinical variables been investigated, 94 publications concluded that there were statistically significant or near significant level of quantitative and/or qualitative differences between AspD and AD/HFA groups; 4 publications found both similarities and differences between the two groups; 30 publications concluded with no differences between the two groups. Although DSM-5 ASD will eliminate Asperger’s disorder. However, it is plausible to predict that the field of ASD would run full circle during the next decade or two and that AspD will be back in the next edition of DSM.

Research in Infantile Autism: A Methodological Problem in Using Language Comprehension as the Basis for Selecting Matched Controls

This study examines the interrelationship between two commonly used tests of language comprehension, the Peabody Picture Vocabulary Test (PPVT) and the Test for Auditory Comprehension of Language (TACL), administered to 35 autistic and 23 nonautistic patients. The results show that these two tests cannot be used interchangeably and suggest that autism studies relying on one test to select language-matched controls may yield inappropriate controls. It is suggested that, until a single valid and reliable comprehensive measure of language comprehension becomes available, an average of the age-related scores obtained from several tests of language comprehension should be used as a basis for selecting language matched controls.

The effects of fenfluramine on communication skills in autistic children

The effect of fenfluramine on communication skills in six autistic males was examined over a 9-month period. Communication behaviors were analyzed via standardized receptive and expressive measures, spontaneous speech samples gathered in the clinic, and videotaped observations of the numbers of noncommunicative utterances, immediate echolalia, and spontaneous initiations. The results demonstrated that fenfluramine had no significant effects on the communication behaviors of these six autistic males.

Utility of the head computerized tomography scan in child and adolescent psychiatry

Despite the widespread use of computerized tomography (CT) in child and adolescent psychiatry, studies have not looked at its overall usefulness in a clinical setting. In this report, the authors examined 122 inpatients who had CT scans of the head. Only 27 patients had an abnormal CT scan. None of the patients had a change made in the diagnosis or treatment as a result of the scan findings. The authors suggest that routine CT scans of the head in child and adolescent inpatients is of limited value. In view of the rising costs of medical investigations, and the risk of irradiation to the developing brain, they suggest the need for clear indications for this procedure in clinical child and adolescent psychiatry.

Comparisons between autistic and nonautistic children on the Test for Auditory Comprehension of Language

Expressive language differences between autistic and nonautistic populations have been a topic of research in the past decade, yet little information is available in regard to the receptive language performances based on standarized tests. Questions as to the existence of sex differences in language have also been raised. The study examines the performance of 19 matched pairs of autistic and nonautistic children on the Test for Auditory Comprehension of Language. As well, the data were analyzed according to sex for each group. The results indicated that there were no significant differences between groups or between the sexes in either group. Questions for further research are raised.