The dependency of age-related change of brain activation on the visual stimuli - Demand-reservation balance
نویسندگان
چکیده
Introduction The important role of fMRI in geriatrics is to assess the change of brain activation related to early signs of cognitive impairments. Various cognitive tasks increased the activation in the frontal or parietal areas in elderly subjects. On the other hand, age-related reduction of BOLD signal in the primary visual area (V1) has been discussed [1 3]. In this study, we investigated the effect of cognitive demand for visual processing on the age-related change of the hemodynamic response function (HRF) in healthy subjects. The characteristics of HRF were compared between V1 and the higher visual associated areas.
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