Faculty Bibliography

The phenotype of attenuated mucopolysaccharidosis type II (MPS II), also called Hunter syndrome, has not been previously studied in systematic manner. In contrast to the "severe" phenotype, the "attenuated" phenotype does not present with behavioral or cognitive impairment; however, the presence of mild behavior and cognitive impairment that might impact long-term functional outcomes is unknown. Previously, significant MRI abnormalities have been found in MPS II. Recent evidence suggests white matter abnormalities in many MPS disorders. METHODS: As the initial cross-sectional analysis of a longitudinal study, we studied the association of brain volumes and somatic disease burden with neuropsychological outcomes, including measures of intelligence, memory, and attention in 20 patients with attenuated MPS II with a mean age of 15.8. MRI volumes were compared to 55 normal controls. RESULTS: While IQ and memory were average, measures of attention were one standard deviation below the average range. Corpus callosum volumes were significantly different from age-matched controls, differing by 22%. Normal age-related volume increases in white matter were not seen in MPS II patients as they were in controls. Somatic disease burden and white matter and corpus callosum volumes were significantly associated with attention deficits. Neither age at evaluation nor age at starting treatment predicted attention outcomes. CONCLUSIONS: Despite average intelligence, attention is compromised in attenuated MPS II. Results confirm an important role of corpus callosum and cortical white matter abnormality in MPS II as well as the somatic disease burden in contributing to attention difficulties. Awareness by the patient and caregivers with appropriate management and symptomatic support will benefit the attenuated MPS II patient.

A previous investigation of the cognitive processes underlying note-taking found that handwriting speed was the only significant predictor of notes, and notes were the only significant predictor of test performance. This investigation sought to extend these results by evaluating the effects of handwriting speed, language comprehension, two measures of working memory (complex span and executive attention) and an outline on note-taking and test performance (written summary). Participants were randomly assigned to an outline or not no-outline group (Group) to determine the effect of an outline on handwriting speed. Results from a path analysis indicated that handwriting speed, language comprehension and Group were significantly related to notes. The relationship between the independent variables and the written summary was not completely mediated by notes as in the previous investigation. Notes, Group and language comprehension were related to the written summary. The implications of the findings are discussed.

Attention-deficit hyperactivity disorder (ADHD) is a frequent comorbidity in children with epilepsy. Despite similarities in behavioral manifestations of inattention and hyperactivity, it is unclear whether the neuropsychological endophenotypes of children with developmental ADHD differ from those with ADHD in the context of epilepsy. The present study compared groups of clinically referred children with both ADHD-Inattentive subtype (ADHD-I) and ADHD-Combined subtype (ADHD-C) to children with ADHD-I and ADHD-C and epilepsy on neuropsychological measures of intellectual functioning, auditory attention, working memory, and sustained attention and response inhibition. Those with ADHD and epilepsy performed more poorly on measures of intellectual function (e.g., Full-Scale IQ, Verbal IQ, Performance IQ) as well as auditory attention and working memory. Differences across the groups were also seen on a continuous performance test. Follow-up correlational analyses showed that variables such as seizure frequency and number of antiepilepsy medications predicted cognitive dysfunction in the epilepsy groups. Overall results suggest that the neuropsychological endophenotypes in developmental ADHD versus ADHD in epilepsy differ with seizure-related variables predicting cognitive dysfunction.

We examined the risk and protective factors and mental health problems of 105 low SES, urban adolescents whose mothers were coping with alcohol abuse and other drug problems. Approximately half of the mothers were also HIV-infected. As hypothesized, there were few differences between adolescents of HIV-infected and HIV-uninfected mothers in background characteristics, mental health issues and current substance use risk behaviors. In addition to maternal substance abuse, youth in both groups experienced similar risk factors including early foster care placement and high levels of maltreatment. Current patterns of emerging risk behaviors were evident among youth in both groups as well as signs of resiliency including high levels of school attendance. These results underscore the importance of interventions for youth of substance abusing mothers, particularly those living in urban poverty.