BOLD Signal Change and Contrast Reversing Frequency: An Event-Related fMRI Study in Human Primary Visual CortexReportar como inadecuado




BOLD Signal Change and Contrast Reversing Frequency: An Event-Related fMRI Study in Human Primary Visual Cortex - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

It is believed that human primary visual cortex V1 increases activity with increasing temporal frequency of a visual stimulus. Two kinds of visual stimulus were used in the previous studies, one is patterned-flash stimulus with a fixed onset period and an increasing average luminance with the increase of temporal frequency, the other is contrast reversing flickering checkerboard or grating with a constant average luminance across different temporal frequencies. That hemodynamic responses change as a function of reversal frequency of contrast reversing checkerboard is at odds with neurophysiological studies in animals and neuroimaging studies in humans. In the present study, we addressed the relationship between reversal frequency of contrast reversing checkerboard and hemodynamic response in human V1 using an event-related experimental paradigm and found that the transient characteristics of blood oxygenation level dependent response in human V1 depended very little on the reversal frequency of a contrast reversing checkerboard.



Autor: Pei Sun , Jianfei Guo, Shichun Guo, Jingyi Chen, Le He, Shimin Fu

Fuente: http://plos.srce.hr/



DESCARGAR PDF




Documentos relacionados