As if the rainfall has stopped, global warming has set in, the wind has increased, the jungle is subjected to the elements, and then tragically declines into a desert wasteland and petrified forest. This original belief after Cajal approved the Neuron Doctrine occurred for obvious reasons. Our brain does get smaller as we age, particularly our cortex, and the complete jungle was considered to have enough room for a lifetime of experience. However, new glial research has shown the brain is more like a living jungle throughout our lifetime than originally thought—with dead trees replaced by new ones and constant spawn and spreading of seeds to spaces suitable for new vegetation. Ground space is limited but growth is constant. One of the largest mistakes of the twentieth century was the notion that after childhood brain development, our brain just remained in the same state until we died. Our neurons were constructed, made connections, and those connections were permanent, similar to a statue constructed to honor our memory, sitting there chipped away by the wind and rain until it crumbled and was covered by dust.
