FIGURE 8-15 Synapse Formation and Pruning Changes in the relative density of synapses in the human visual cortex and prefrontal cortex (its frontmost part) as a function of age.

Data from J.-P. Bourgeois (2001). Synaptogenesis in the neocortex of the newborn: The ultimate frontier for individuation?” In C. A. Nelson and M. Luciana (Eds.), Handbook of developmental cognitive neuroscience. Cambridge, MA: MIT Press.