Sensory Processing in Williams Syndrome: Individual differences and changes over time.

This study examined individual differences as well as the development of sensory processing difficulties in children with Williams syndrome (WS) using a cross-sectional (Experiment 1) and longitudinal design (Experiment 2). In Experiment 1, a clustering approach of sensory processing scores suggested two groups. Experiment 2 showed that the clusters identified in Experiment 1 were not stable across development, especially for those with high sensory impairments at either time point. Yet, most children experienced high impairments in sensory registration at both time points, suggesting impaired registration is a core phenotype of sensory processing in children with WS across development. Possible mechanisms, limitations and implications are discussed.

Evaluation of the accuracy of two regression-based methods for estimating premorbid IQ.

Two premorbid IQ estimation procedures were compared in a normal, non-brain-impaired sample and a clinical sample of known brain-impaired individuals. The methods used for comparison were the purely demographically based regression index (DI) developed by and the Oklahoma Premorbid Intelligence Estimate (OPIE) equation by, which uses demographic information combined with current performance tasks. The data for the normal sample were gathered from the WAIS-R standardization sample of 1880 subjects. The clinical sample was 100 patients with known cognitive impairment who had been referred to a private neuropsychology practice. The DI appeared to provide the most clinical utility as an estimate of premorbid IQ in a cognitively impaired sample. Significant differences between the two methods for specific locations of brain injury were not observed.