A case-control study of visual, auditory and audio-visual sensory interactions in children with autism spectrum disorder.

To assess the relative integrity of early visual and auditory processes in autism spectrum disorder (ASD), we used frequency-tagged visual and auditory stimulation and high-density electroencephalogram recordings of unimodal and dual-modality responses in a case-control design. To test for the specificity of effects on ASD, we recorded from a smaller group of children with attention-deficit hyperactivity disorder (ADHD). Horizontal 3 cycle per degree (cpd) gratings were presented at 5 Hz, and a random stream of /ba/, /da/, /ga/ syllables was presented at 6 Hz. Grating contrast response functions were measured unimodally and in the presence of a 64-dB auditory input. Auditory response functions were measured unimodally and in the presence of a 40% contrast grating. Children with ASD (n = 34) and ADHD (n = 13) showed a common lack of audio-visual interaction compared to typically developing children (n = 40) when measured at the first harmonic of the visual stimulus frequency. Both patient groups also showed depressed first harmonic responses at low contrast, but the ADHD group had consistently higher first-harmonic responses at high contrast. Children with ASD had a preferential loss of second-harmonic (transient) responses. The alteredtransient responses in ASD are likely to arise very early in the visual pathway and could thus have downstream consequences for many other visual mechanisms and processes. The alteration in audio-visual interaction could be a signature of a comorbid phenotype shared by ASD and ADHD, possibly due to alterations in attentional selection systems.

Effect of Vitamin D Replacement on Cognition in Multiple Sclerosis Patients.

Multiple Sclerosis is associated with deficient serum 25 hydroxyvitamin D (25 (OH)D) level and cognitive impairment. The aim of this study is to evaluate cognitive performance in MS patients with deficient 25 (OH)D (<25 ng/ml) compared to patients with sufficient levels (>35 ng/ml), then to evaluate the change in cognitive performance after 3 months of vitamin D3 oral replacement. Eighty-eight MS patients with relapsing remitting and clinically isolated type of MS, older than 18 years treated with interferon beta were enrolled. Cognitive testing was performed at baseline and at 3 months using the Montreal Cognitive Assessment (MoCA), Stroop, Symbol Digit Modalities (SDMT) and Brief Visuospatial Memory Test (BVMT-R). Serum 25 (OH)D was measured at baseline and at the end of the study. Vitamin D3 replacement improved the MS patients' cognitive performance after 3 months on the MoCA and BVMT-Delayed Recall (DR). Sufficient serum 25 (OH)D level predicted better cognitive performance on the BVMT-DR at baseline (ß: 1.74, p: <0.008) and 3 months (ß: 1.93, p: <0.01) after adjusting for all measured confounding variables. Vitamin D3 replacement could improve cognitive performance in MS patients and make a significant difference in the patient's quality of life.

Retinal measures correlate with cognitive and physical disability in early multiple sclerosis.

Further studies are needed to determine the role of retinal optical coherence tomography (OCT) in non-optic neuritis (ON) eyes of patients with early MS. The objective of this study is to explore the relationship between retinal layers' thickness and cognitive as well as physical disability in patients with the early RRMS. Participants in this cross-sectional study were adults with early RRMS, stable on interferon beta-1a, or fingolimod therapy, and without a history of ON in one or both eyes. Patients were evaluated clinically, underwent a battery of cognitive tests, and a retinal OCT scan which was also performed on a group of healthy age- and gender-matched controls. We studied 47 patients with RRMS, on interferon beta-1a (N = 32) or fingolimod (N = 15), and 18 healthy controls. Multivariate analyses controlling for age, disease duration, treatment, and education when exploring cognitive function, showed that pRNFL thickness correlated negatively with 9HPT (standardized Beta -0.4, p < 0.0001), and positively with SDMT (standardized Beta 0.72, p = 0.007). In patients with early RRMS without optic neuropathy, retinal thickness measures correlated with physical disability and cognitive disability, supporting their potential as biomarkers of axonal loss.