Identification of the visual landmark pathway in the mammalian brain

Abstract

A central question in neuroscience is how the mammalian brain processes information from the outside world. In primates, visual information is conveyed to the cortex primarily via the lateral geniculate nucleus (LGN) of the thalamus, and secondarily through the superior colliculus. In rodents the converse is true: only a minority of retinal outputs project to the LGN, while 90% project to the superior colliculus (e.g. Ellis et al., 2016). Thus, it has been unclear how visual information from the outside world, for example visual landmarks that rodents use for orientation and navigation, is processed in the rodent brain. The study by Street and Jeffery in this issue of The Journal of Physiology, however, now provides a compelling answer: visual landmark information travels via the LGN, even in rodents.