Neurons in the nervous system make connections with ascending feedforward projections and descending feedback projections,as well as projections from neural structures at the identical hierarchical level.These neurons form extremely complicated neural networks and pathways.Compared with the role of the feedforward projection,much less is known concerning the functional roles of the feedback projection.Visual cortex is a good model for studying functional roles of cortical feedback projections which involve many high functions,such as attention,searching and cognition.The present review mainly focused on the functional roles of feedback projections in the visual system.
Glaucoma is closely related to elevation of intraocular pressure （IOP）. Many studies have done on the effect of chronic elevation of lOP on the retina and optic nerve, but less attention was paid to the effect of acute elevated lOP. Here we briefly review experimental studies on functional changes of the visual system from the retina to the visual cortex under acute elevated lOP condition, which is similar to that of acute primary angle-closure glaucoma.
The amygdaloid complex receives information from all sensory systems, especially from vision. Some researches (Amaral DG, 2003) show that in the primate brain, the amygdala
Yuanxin Chen, Bin Zhu and Tiande Shou School of Life Sciences, Fudan University, Shanghai, P.R.China
