1. Bohm HV, Stewart MG. {{Brief Report: On the Concordance Percentages for Autistic Spectrum Disorder of Twins}}.{ J Autism Dev Disord};2009 (Jan 16)
In the development of genetic theories of Autistic Spectrum Disorder (ASD) various characteristics of monozygotic (MZ) and dizygotic (DZ) twins are often considered. This paper sets forth a possible refinement in the interpretation of the MZ twin concordance percentages for ASD underlying such genetic theories, and, drawing the consequences from that refinement, a possible early environmental factor in the later development of ASD.
2. Casanova MF, El-Baz A, Mott M, Mannheim G, Hassan H, Fahmi R, Giedd J, Rumsey JM, Switala AE, Farag A. {{Reduced Gyral Window and Corpus Callosum Size in Autism: Possible Macroscopic Correlates of a Minicolumnopathy}}. {J Autism Dev Disord};2009 (Jan 16)
Minicolumnar changes that generalize throughout a significant portion of the cortex have macroscopic structural correlates that may be visualized with modern structural neuroimaging techniques. In magnetic resonance images (MRIs) of fourteen autistic patients and 28 controls, the present study found macroscopic morphological correlates to recent neuropathological findings suggesting a minicolumnopathy in autism. Autistic patients manifested a significant reduction in the aperture for afferent/efferent cortical connections, i.e., gyral window. Furthermore, the size of the gyral window directly correlated to the size of the corpus callosum. A reduced gyral window constrains the possible size of projection fibers and biases connectivity towards shorter corticocortical fibers at the expense of longer association/commisural fibers. The findings may help explain abnormalities in motor skill development, differences in postnatal brain growth, and the regression of acquired functions observed in some autistic patients.
3. Groen WB, van Orsouw L, Huurne NT, Swinkels S, van der Gaag RJ, Buitelaar JK, Zwiers MP. {{Intact Spectral but Abnormal Temporal Processing of Auditory Stimuli in Autism}}. {J Autism Dev Disord};2009 (Jan 16)
The perceptual pattern in autism has been related to either a specific localized processing deficit or a pathway-independent, complexity-specific anomaly. We examined auditory perception in autism using an auditory disembedding task that required spectral and temporal integration. 23 children with high-functioning-autism and 23 matched controls participated. Participants were presented with two-syllable words embedded in various auditory backgrounds (pink noise, moving ripple, amplitude-modulated pink noise, amplitude-modulated moving ripple) to assess speech-in-noise-reception thresholds. The gain in signal perception of pink noise with temporal dips relative to pink noise without temporal dips was smaller in children with autism (p = 0.008). Thus, the autism group was less able to integrate auditory information present in temporal dips in background sound, supporting the complexity-specific perceptual account.
4. Handen BL, Melmed RD, Hansen RL, Aman MG, Burnham DL, Bruss JB, McDougle CJ. {{A Double-Blind, Placebo-Controlled Trial of Oral Human Immunoglobulin for Gastrointestinal Dysfunction in Children with Autistic Disorder}}. {J Autism Dev Disord};2009 (Jan 16)
Controversy exists regarding the extent and possible causal relationship between gastrointestinal symptoms and autism. A randomized, double-blind, placebo-controlled, parallel groups, dose-ranging study of oral, human immunoglobulin (IGOH 140, 420, or 840 mg/day) was utilized with 125 children (ages 2-17 years) with autism and persistent GI symptoms. Endpoint analysis revealed no significant differences across treatment groups on a modified global improvement scale (validated in irritable bowel syndrome studies), number of daily bowel movements, days of constipation, or severity of problem behaviors. IGOH was well-tolerated; there were no serious adverse events. This study demonstrates the importance of conducting rigorous trials in children with autism and casts doubt on one GI mechanism presumed to exert etiological and/or symptomatic effects in this population.
5. Schwartzman F, Vitolo MR, Schwartzman JS, Morais MB. {{Eating practices, nutritional status and constipation in patients with Rett syndrome}}. {Arq Gastroenterol};2008 (Oct-Dec);45(4):284-289.
BACKGROUND: Disturbance in chewing, swallowing and digestive motility may predispose to feeding and nutritional abnormalities in patients with Rett syndrome. OBJECTIVE: To evaluate the dietary habits, nutritional status and the prevalence of constipation in patients with classical Rett syndrome. METHODS: Twenty seven female patients between the ages of 2.6 and 21.8 years were studied. The following parameters were evaluated: food register, weight, height and intestinal movement characteristics. Weight and height were compared with the National Center for Health Statistics standards. RESULTS: The inability to ingest solid foods was observed in 80.8% of the patients. A height-to-age deficit was observed in 13 (48.1%) of the girls, being more intense in patients at stage IV. Weight-for-height deficit was found in 10 (37.0%) patients, 15 (55.6%) showed normal weight and 2 (7.4%) were overweight for their height. The median ingestion of energy, according to weight-for-height, was equal to 106.6%. Insufficient iron ingestion was observed in 63.0% and insufficient calcium in 55.6% of the patients. Constipation was verified in 74.1% of the patients and did not show a relationship with the quantity of fiber in the diet. CONCLUSION: Various nutritional problems, as well as, intestinal constipation were observed in these patients with Rett syndrome, and they must be considered in the multidisciplinary therapeutic planning of these individuals.
6. Singh J, Illes J, Lazzeroni L, Hallmayer J. {{Trends in US Autism Research Funding}}. {J Autism Dev Disord};2009 (Jan 16)
This study shows that the number of autism research grants funded in the US from 1997 to 2006 significantly increased 15% per year. Although the majority of projects were concentrated in basic science (65%) compared to clinical (15%) and translational research (20%), there is a significant decrease in the proportion of basic research grants per year and a significant increase in the proportion of translational projects per year. The number of translational projects funded by the National Alliance for Autism Research and Cure Autism Now increased significantly, whereas the number of clinical projects significantly increased for the National Institutes of Health. In conclusion, this study demonstrates the shifting landscape of autism research from basic science to clinical and translational research.
7. Wallace GL, Anderson M, Happe F. {{Brief Report: Information Processing Speed is Intact in Autism but not Correlated with Measured Intelligence}}. {J Autism Dev Disord};2009 (Jan 16)
Speed of information processing, as measured by inspection time (IT), is a robust predictor of intellectual functioning. However, among individuals with autism and low IQ scores, IT has been reported to be discrepantly fast, and equal to that of high IQ typically developing children (Scheuffgen et al. in Dev Psychopathol 12: 83-90, 2000). The present investigation replicates and extends this study by examining IT and its relationship to IQ in a higher functioning (average range mean IQ) group of children with autism spectrum disorders (ASD) versus matched controls. Though IT was not significantly faster in the ASD group than in the matched control group, the relationship between IT and IQ was uniquely discrepant for the ASD group, partially corroborating and extending previous findings.
