1. Gage NM, Juranek J, Filipek PA, Osann K, Flodman P, Isenberg AL, Spence MA. {{Rightward hemispheric asymmetries in auditory language cortex in children with autistic disorder: an MRI investigation}}. {J Neurodev Disord};2009 (Sep);1(3):205-214.
Purpose: determine if language disorder in children with autistic disorder (AD) corresponds to abnormalities in hemispheric asymmetries in auditory language cortex. Methods: MRI morphometric study in children with AD (n = 50) to assess hemispheric asymmetries in auditory language cortex. A key region of interest was the planum temporale (PT), which is larger in the left hemisphere in most healthy individuals. Results: (i) Heschl’s gyrus and planum polare showed typical hemisphere asymmetry patterns; (ii) posterior Superior Temporal Gyrus (pSTG) showed significant rightward asymmetry; and (iii) PT showed a trend for rightward asymmetry that was significant when constrained to right-handed boys (n = 30). For right-handed boys, symmetry indices for pSTG were significantly positively correlated with those for PT. PT asymmetry was age dependent, with greater rightward asymmetry with age. Conclusions: results provide evidence for rightward asymmetry in auditory association areas (pSTG and PT) known to subserve language processing. Cumulatively, our data provide evidence for a differing maturational path for PT for lower functioning children with AD, with both pre- and post-natal experience likely playing a role in PT asymmetry. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11689-009-9010-2) contains supplementary material, which is available to authorized users.
2. Hollander E, Wang AT, Braun A, Marsh L. {{Neurological considerations: Autism and Parkinson’s disease}}. {Psychiatry Res};2009 (Oct 6)
Within the spectrum of disorders that manifest obsessive-compulsive (OC) features lies a sub-cluster of neurological conditions. Autism and Parkinson’s disease (PD) are examples of two such neurological disorders that seem quite dissimilar on the surface. Yet, both conditions can include repetitive behaviors of a compulsive-impulsive nature. Furthermore, while autism and PD differ in other associated symptom domains that shape the course of each disorder, both disorders share some phenomenology in the core domain of repetitive behaviors and involve basal ganglia and frontal lobe dysfunction, similar to OC disorder (OCD). Accordingly, examination of the similarities and differences between autism and PD may provide insight into the pathophysiology and treatment of OC spectrum disorders. The current review focuses on the phenomenology, comorbidity, course of illness, family history, brain circuitry, and treatment of autism and PD, as they relate to OCD and OC spectrum disturbances.
3. Hufnagle D, Holt LL, Thiessen ED. {{Autistic traits predict individual differences in speech categorization}}. {J Acoust Soc Am};2009 (Oct);126(4):2300.
Investigating individual differences in speech perception using measures of « autistic » traits in neurotypicals can gauge natural variability in speech processing [M. Stewart and M. Ota, Cognition 109, 157-162 (2008)]. Using the autism-spectrum quotient (AQ) [Baron-Cohen et al., J. Autism & Dev. Disord. 31, 5-25 (2001)], which measures autistic traits in neurotypicals, we investigated individual differences in context-dependent speech processing. Twenty-eight neurotypicals categorized a nine-step daga series in the context of non-speech tone precursors [following L. Holt, Psychol. Sci. 16, 305-312 (2005)] and completed the AQ. Context included three tone groups, including relatively high (shift toward ga), medium, and low (shift toward da) tones. Overall, the temporally adjacent tone grouping shifted perception more than distant context (p<0.001). Effects correlated with AQ (r=0.53). Lower AQ (fewer autistic traits) is associated with near-zero context dependence for endpoint categorization and large context-dependence for ambiguous speech-target categorization. Higher AQ is associated with intermediate influence of context across the series. Individual differences in context-dependent phonetic processing can be predicted from a personality trait scale, suggesting that phonetic processing is not immune from the influence of higher-order cognitive processes associated with these traits or that lower-level perceptual processing varies with these traits. [Work supported by NIH.].
4. Kaiser MD, Shiffrar M. {{The visual perception of motion by observers with autism spectrum disorders: A review and synthesis}}. {Psychon Bull Rev};2009 (Oct);16(5):761-777.
Traditionally, psychological research on autism spectrum disorder (ASD) has focused on social and cognitive abilities. Vision provides an important input channel to both of these processes, and, increasingly, researchers are investigating whether observers with ASD differ from typical observers in their visual percepts. Recently, significant controversies have arisen over whether observers with ASD differ from typical observers in their visual analyses of movement. Initial studies suggested that observers with ASD experience significant deficits in their visual sensitivity to coherent motion in random dot displays but not to point-light displays of human motion. More recent evidence suggests exactly the opposite: that observers with ASD do not differ from typical observers in their visual sensitivity to coherent motion in random dot displays, but do differ from typical observers in their visual sensitivity to human motion. This review examines these apparently conflicting results, notes gaps in previous findings, suggests a potentially unifying hypothesis, and identifies areas ripe for future research.
5. Romero-Munguia MA. {{[Non-verbal learning disorder versus autism spectrum disorder: the role of procedural learning.]}}. {Rev Neurol};2009 (Oct 16-31);49(8):448.Trastorno de aprendizaje no verbal frente a trastorno del espectro autista: el papel del aprendizaje procesal.
