Two eyes are better than one! Our brains integrate two slightly different images coming from our two eyes to give us depth perception. How does this happen? To answer this, we will look at where the neural pathways from the two eyes converge. Retinal ganglion cells (RGCs) are neurons in the eye that send visual information to the brain. RGCs are divided into many subtypes based on the shapes of the cells. The lateral geniculate nucleus (LGN) is the primary brain region where RGCs first deliver visual information to brain cells. Previous studies have suggested that some LGN cells receive input from only one eye (Chen and Regehr, 2000; Sincich et al., 2007), while others receive input from both eyes (Hammer et al., 2015; Morgan et al., 2016). To fully understand how the brain integrates the images coming from two eyes, we need to understand the pattern of connectivity between RGCs and LGN cells at the level of individual neuronal connections.

When we’re walking from place to place, we have full control of when and how fast to go. But how does the brain tell the leg muscles to start walking? Speed up? Slow down?