Narrator: This is Science Today. What sets the human brain apart from other species? According to Dr. George Bartzokis, director of the UCLA Memory Disorders and Alzheimer's disease Clinic, it's myelin – the fatty insulation that coats a neuron's axon. Bartzokis explains that humans have more myelin, percentage-wise, than other species and that allows us to be human.
Bartzokis: And unfortunately, we also get uniquely humans diseases. There are not many primates that develop schizophrenia and in older age in fact, the developmental Alzheimer's disease basically occurs only in humans. We're unique; both in the amount of myelination we get in our brain and the fact that we get these diseases and they all seem to involve either a problem in the development of myelin or in its degeneration.
Narrator: Myelin helps our neurons signal efficiently and improves the overall function of our brain's wiring system. For Science Today, I'm Larissa Branin.