1. Fernell E, Eriksson MA, Gillberg C. {{Early diagnosis of autism and impact on prognosis: a narrative review}}. {Clin Epidemiol};2013;5:33-43.
Autism spectrum disorders involve a set of clinical phenotypes that mirror an early onset of neurodevelopmental deviations, with core symptoms that can probably be related to a deficiency in the social instinct. Underlying the cognitive impairments there are physiological brain problems, caused by a large number of medical factors. This narrative review of systematic reviews and meta-analyses from the last 5 years (2008-2012) presents aspects from many areas in autism spectrum disorder research, with a particular focus on early intervention and the subsequent impact on prognosis. Other major areas discussed are epidemiology, early symptoms and screening, early diagnosis, neuropsychology, medical factors, and the existence of comorbidities. There is limited evidence that any of the broadband « early intervention » programs are effective in changing the natural long-term outcome for many individuals with an early diagnosis of autism. However, there is some evidence that Early Intensive Behavioral Intervention (EIBI) is an effective treatment for some children with ASD. Nevertheless, there is emerging consensus that early diagnosis and information are needed in order that an autism-friendly environment be « created » around affected individuals.
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2. Rotschafer S, Razak K. {{Altered Auditory Processing in a Mouse Model of Fragile X Syndrome}}. {Brain Res};2013 (Feb 28)
This study provides the first description of auditory cortical processing in a mouse model of Fragile X Syndrome (FXS). FXS is a genetic cause of intellectual impairment and is an autism spectrum disorder. Human studies with auditory evoked potentials indicate that FXS is associated with abnormal auditory processing. The Fmr1 knock-out (KO) mouse is a useful model for studying FXS. The KO mice show acoustic hypersensitivity and propensity for audiogenic seizures, suggesting altered auditory responses. However, the nature of changes at the neuronal level is not known. Here we conducted in vivo single unit extracellular electrophysiology in the auditory cortex of urethane/xylazine-anesthetized Fmr1 KO mice in response to tones and frequency modulated (FM) sweeps. Using tones as stimuli, we report expanded frequency tuning, enhanced response magnitude, and more variable first spike latencies in Fmr1 KO mice compared to wild-type control. FM sweep stimuli revealed altered sensitivity to the rate of frequency change indicating abnormal spectrotemporal processing. There was no difference in FM sweep direction selectivity. Consistent with studies of the somatosensory cortex, these data point to hyper-responsiveness of auditory neurons as a key processing abnormality in FXS. Auditory neural responses can serve as outcome measures in preclinical trials of therapeutics for FXS as well as serve as physiological probes to study their mechanisms of action.
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3. Wodka EL, Mathy P, Kalb L. {{Predictors of Phrase and Fluent Speech in Children With Autism and Severe Language Delay}}. {Pediatrics};2013 (Mar 4)
OBJECTIVE:To examine the prevalence and predictors of language attainment in children with autism spectrum disorder (ASD) and severe language delay. We hypothesized greater autism symptomatology and lower intelligence among children who do not attain phrase/fluent speech, with nonverbal intelligence and social engagement emerging as the strongest predictors of outcome.METHODS:Data used for the current study were from 535 children with ASD who were at least 8 years of age (mean = 11.6 years, SD = 2.73 years) and who did not acquire phrase speech before age 4. Logistic and Cox proportionate hazards regression analyses examined predictors of phrase and fluent speech attainment and age at acquisition, respectively.RESULTS:A total of 372 children (70%) attained phrase speech and 253 children (47%) attained fluent speech at or after age 4. No demographic or child psychiatric characteristics were associated with phrase speech attainment after age 4, whereas slightly older age and increased internalizing symptoms were associated with fluent speech. In the multivariate analyses, higher nonverbal IQ and less social impairment were both independently associated with the acquisition of phrase and fluent speech, as well as earlier age at acquisition. Stereotyped behavior/repetitive interests and sensory interests were not associated with delayed speech acquisition.CONCLUSIONS:This study highlights that many severely language-delayed children in the present sample attained phrase or fluent speech at or after age 4 years. These data also implicate the importance of evaluating and considering nonverbal skills, both cognitive and social, when developing interventions and setting goals for language development.
