\s=b\The vestibulo-ocular reflex (VOR) is seldom tested above 2 Hz, in spite of the higher-frequency components that stimulate it during natural head movements. We tested the horizontal VOR in ten normal subjects during 18 s of active, side-to\x=req-\ side head motion over a frequency range from 2 to 6 Hz. Audible clicks were used as a linearly increasing frequency cue. Head velocity was monitored. The two experimental conditions were head movement while fixating a stationary wal l \x=req-\ mounted target in dim light, and head movement in darkness with an imagined stationary target. Computed gain and phase results of the two test conditions were not significantly different, due to inactivation of the smooth pursuit system above 2 Hz. We conclude that higher\x=req-\ frequency VOR responses can be tested in the light by a brief, low-cost test, which does not require expensive rotating machinery.A frequent complaint among pa¬ tients with dizziness is a sensa¬ tion of dizziness following head move-

Previous studies have demonstrated effects of racial and socioeconomic factors on survival of adults with cancer. While less studied in the pediatric population, data exist demonstrating disparities of care and survival in pediatric oncology patients based on socioeconomic and racial/ethnic factors. Brain cancers recently overtook leukemia as the number one cause of childhood cancer fatalities, but demographic and socioeconomic disparities in these tumors have not been adequately studied. We obtained data from the SeeR program of the national cancer institute (nci). We selected patients under 19 years of age with central nervous system (CNS) cancers diagnosed between 2000 and 2015. We included patient demographics, tumor characteristics, treatment, and socioeconomic characteristics as covariates in the analysis. We measured overall survival and extent of disease at diagnosis. We saw that Black and Hispanic patients overall had a higher risk of death than non-Hispanic White patients on multivariable analysis. On stratified analysis, Black and Hispanic patients with both metastatic and localized disease at diagnosis had a higher risk of death compared to White, non-Hispanic patients, although the difference in Black patients was not significant after adjusting for mediating factors. However, our findings on extent of disease at diagnosis demonstrated that neither Black race nor Hispanic ethnicity increased the chance of metastatic disease at presentation when controlling for mediating variables. In summary, racial and ethnic disparities in childhood CNS tumor survival appear to have their roots at least partially in post-diagnosis factors, potentially due to the lack of access to high quality care, leading to poorer overall outcomes.

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