She notes that children raised in orphanages can turn out just fine, citing the fact that many of them marry and have children. It seems important to ask not whether they have families and children, but rather how those families do. In fact, Harris seems to avoid asking whether the way a child is raised influences the way that child will act as a parent. Both achieve their effects by altering the synaptic organization of the brain. Synapses are the connection points between brain cells that allow the cells to communicate with each other.
Synapses are responsible for much of the brain's activity.
The particular patterns of synapses in a person's brain, and the information that those connections encode, are the keys to who that person is. But experience alters synapses as well, either creating new ones or changing the strength of existing ones. Our ability to see the world the same way other humans do is programmed in us. But unless we have the right kinds of visual experiences at the right time, synapses in the visual system of the brain won't develop normally and, as a result, we will not see normally. For example, if a child's eyes are misaligned during a certain period in early life, the brain's visual system is deprived of depth cues and depth perception is impaired.