کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1806608 | 1025219 | 2011 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Activation of SC during electrical stimulation of LGN: retinal antidromic stimulation or corticocollicular activation? Activation of SC during electrical stimulation of LGN: retinal antidromic stimulation or corticocollicular activation?](/preview/png/1806608.png)
We have recently used combined electrostimulation, neurophysiology, microinjection and functional magnetic resonance imaging (fMRI) to study the cortical activity patterns elicited during stimulation of cortical afferents in monkeys. We found that stimulation of a site in lateral geniculate nucleus (LGN) increases the fMRI signal in the regions of primary visual cortex receiving input from that site, but suppresses it in the retinotopically matched regions of extrastriate cortex. Intracortical injection experiments showed that such suppression is due to synaptic inhibition. During these experiments, we have consistently observed activation of superior colliculus (SC) following LGN stimulation. Since LGN does not directly project to SC, the current study investigated the origin of SC activation. By examining experimental manipulations inactivating the primary visual cortex, we present here evidence that the robust SC activation, which follows the stimulation of LGN, is due to the activation of corticocollicular pathway.
Journal: Magnetic Resonance Imaging - Volume 29, Issue 10, December 2011, Pages 1351–1357