When Does the Cerebrum Develop in a Fetus?

During weeks 8 to 10, the cerebrum begins its development in earnest. Neurons proliferate and begin their migration throughout the brain. The anterior commissure, which is the first interhemispheric connection (a small one), also develops. Reflexes appear for the first time during this period.

At what week is a baby's brain fully developed?

At just six weeks, the embryo's brain and nervous system begin to develop, although the complex parts of the brain continue to grow and develop through the end of pregnancy, with development ending around the age of 25.

At what point does a fetus have brain activity?

The very beginnings of our higher brain structures only start to appear between weeks 12 and 16. Crucially, the co-ordinated brain activity required for consciousness does not occur until 24-25 weeks of pregnancy.