Differences between male and female brains

Your brain is more complex and powerful than the world's biggest supercomputer, built while you're a baby growing in the womb from the recipes encoded in your genes. But how do your growing brain cells know which genes to use? The answer comes from epigenetic modifications - the special chemical markers that are put on your genes that help cells switch them on or off at the right time and in the right place. Helen Spiers from Kings College London has been finding out how these epigenetic changes are involved in building the brain, and how they could explain some of the differences between male and female brains.