Aberrant eye gaze mechanisms have been implicated in autism spectrum disorders (ASD). Studies of eye movements in children with ASD reveal diminished eye gaze duration and lack of specific eye gaze fixation to the eyes and/or mouth compared with controls. However, findings to date have been contradictory. We examined eye-tracking studies on face processing in children with ASD and conducted meta-analyses to examine whether these children demonstrate atypical fixation on primary facial regions. Twenty eye-tracking studies in children with ASD were reviewed, of which the results from 14 studies were incorporated in the meta-analyses that evaluated fixation duration on (i) eyes (eight studies) and (ii) mouth (six studies). The results reveal that children with ASD have significantly reduced gaze fixation to the eye region of faces. The results of the meta-analyses indicate that ASD patients have significant impairments in gaze fixation to the eyes. On the other hand, no significant difference was uncovered in terms of fixation to the mouth region; however, this finding needs to be interpreted with caution because of the significant heterogeneity in the mouth fixation studies. The findings of this meta-analysis add further clarity to an expanding literature and suggest that specific eye gaze fixation to the eye region may represent a robust biomarker for the condition. The heterogeneity associated with the mouth fixation data precludes any definitive statement as to the robustness of these findings.

Dyslexia is a neurodevelopmental disorder estimated to affect between 4 and 7% of the population. It is often referred to as a learning disability and is characterized by deficits in the linguistic system. To better understand the neural underpinnings of dyslexia, we examined the electroencephalography (EEG) power spectra between pre-adolescents with dyslexia and neurotypical control children during eyes closed state. We reported the differences in spontaneous oscillatory activity of each major EEG band (delta, theta, alpha, and beta) adopting a global as well as in a region-by-region and hemispheric approach to elucidate whether there are changes in asymmetry in children with dyslexia compared to controls. We also examined the relationship between EEG power spectra and clinical variables. The findings of our study confirm the presence of an atypical linguistic network, evident in children with dyslexia. This abnormal network hallmarked by a dominance of theta activity suggests that these abnormalities are present prior to these children learning to read, thus implicating delayed maturation and abnormal hypoarousal mechanisms.

To elucidate the timing and the nature of neural disturbances in dyslexia and to further understand the topographical distribution of these, we examined entire brain regions employing the non-invasive auditory oddball P300 paradigm in children with dyslexia and neurotypical controls. Our findings revealed abnormalities for the dyslexia group in (i) P300 latency, globally, but greatest in frontal brain regions and (ii) decreased P300 amplitude confined to the central brain regions (Fig. 1). These findings reflect abnormalities associated with a diminished capacity to process mental workload as well as delayed processing of this information in children with dyslexia. Furthermore, the topographical distribution of these findings suggests a distinct spatial distribution for the observed P300 abnormalities. This information may be useful in future therapeutic or brain stimulation intervention trials.

The increasing prevalence of autism spectrum disorders (ASD) and limitations in existing treatment options have led parents to seek out treatments such as sound-based training programs. Recent studies have sought to integrate neuroimaging techniques with sound-based interventions in ASD. Given the increasing popularity of these interventions and the paucity of existing research into sound-based therapies, there is significant interest in elucidating the mechanisms by which these therapies impact atypical auditory processing, as well as in the design and refinement of intervention techniques. This paper aims to review the extant literature addressing atypical auditory processing within the ASD population andcurrent sound-based interventions in the context of behavioral, neuroimaging, and neurophysiological domains. The evidence for its effectiveness as an early intervention tool in the treatment of ASD is discussed and suggestions for future directions are offered.