Elon Musk's Neuralink is on the verge of beginning human testing, and the technology that could potentially help people suffering from all sorts of neurologic disabilities ... there's also potential for massive danger. Dr. Marcello Ienca, a professor of artificial intelligence, joined us on "TMZ Live" to explain how Neuralink can advance medicine by light years ... tackling brain disorders that affect hundreds of millions of people, and even quadriplegia.