When fetal brains are exposed to decreased oxygen and blood flow (hypoxia and ischemia), the neurons do not appear to mature normally. On the left is a tracing of a brain cell (neuron) from a control (Con) animal showing normal development of its complex branching pattern. On the right is a tracing of a neuron of the same age as the control, which was exposed to a brief period of hypoxia/ischemia (HI). This cell displays fewer processes and a simpler branch pattern. Thus, despite being the same age as the control animal, brain cells in the HI animal are more immature.