This week’s Journal of Neuroscience is very compatible with a recent posting about http://www.dormivigilia.com/?p=1814. British neuroscientists have further elucidated neuroanatomical pathologies underlying autism spectrum disorder. Comparable to most mental disorders cataloged in the DSM-IV (soon to be DSM V!!), autism spectrum disorder (ASD). encompasses mild (Asperger’s syndrome) and severe (full-blown autism) cases of the disorder that are clinically diagnosed from the age at which the child first speaks. Those who speak before 36 months are commonly diagnosed with Asperger’s syndrome, while those who speak after 36 months of age typically have full-blown autism. In this study, the researchers holistically compared cortical volumes between individuals with ASD and without. Of those having ASD, none of the diagnoses were co-morbid with another psychiatric disorder or mental condition (epilepsy, diabetes, etc). Through the analyses of brain foldings and volumes in the frontal, temporal, and parietal cortices, the researchers discovered differential cortical volumes between ASD-diagnosed and control participants. For example, ASD individuals had more cortical mass in temporal areas, the anterior cingulate gyrus, and orbitofrontal cortex. Control patients had more cortical mass in the frontal association and parietal areas.

What does it all mean?

As we know, many autistic individuals have phenomenal photographic memories and/or multilinguistic. It’s no surprise that increased cortical volume in specific areas of the brain (the temporal cortex) complement these impressive talents. Also, while watching Temple Grandin the other day, I noticed that she was astutely attentive to complicated objects and patterns, such as pulley systems and busy wallpapers, and would subsequently, calculate angular and architectural dimensions of the objects or form convoluted patterns from the wallpapers in her head. Most people do not possess this magnitude of attentiveness. She also was terrified of entering automatic doors because she equated them with the guillotine used to decapitate cows on her aunt’s farm, and therefore, found it too risky to enter a store with an automatic door. This autistic-stereotypic behavior of Temple Grandin nicely complements the present findings, as the potentiated cortical volume found in the anterior cingulate cortex and orbitofrontal cortex of ASD individuals regulates attention and risk-taking, respectively.

ResearchBlogging.orgTo compare control subjects with ASD individuals, it’s also no surprise that the control group had more representative cortical matter in the frontal association and parietal regions. Though autistic individuals have genius-like talents, including a photographic memory and multilinguism, most have an IQ around 80, limited speech, and poor social intelligence. Though I’m certainly not an expert in autistic research, perhaps it is reduced cortical volumes in these frontal association and parietal regions involved with complex cognition (reading social cues and problem solving) that contribute to the vast cognitive and social differences of autistic individuals. I refrain from using handicap here, because as Temple Grandin said routinely throughout the movie, “I’m different, but no less.”

Christine Ecker,1 Andre Marquand,2 Janaina Mourão-Miranda,3,4 Patrick Johnston,1 Eileen M. Daly,1, Michael J. Brammer,2 Stefanos Maltezos,1 Clodagh M. Murphy,1 Dene Robertson,1 Steven C. Williams,3, & and Declan G. M. Murphy1 (30). Describing the Brain in Autism in FiveDimensions—Magnetic
Resonance Imaging-Assisted Diagnosis of Autism Spectrum
Disorder Using a Multiparameter Classification Approach Journal of Neuroscience (32) : 10.1523/JNEUROSCI.5413-09.2010