Knowledge regarding brain development during the first two years of life has been quite limited. MRI study results released in late 2008 has shown that development during this period of time is extremely dynamic, driven mainly by gray matter growth. In contrast, white matter growth was much slower. Not surprisingly, life experiences during this period impact brain development and, according to the researchers, may also play a role in neurodevelopmental disorders, including autism and schizophrenia. (Source)