For most of her career, the physiologist Carmen Estrada, 74, dedicated herself to scientific research, specializing in the blood supply of the brain and its ability to form new neurons throughout life. "The more we exercise a function, the more neurons are recruited, so we can model our brain," she says.

Legislators in Colorado have passed the first law in the United States meant to protect a consumer's brainwaves. While advances in neurotechnology such as brain-computer interfaces that can translate a person's thoughts into actions may bring relief to many, including those with physical impairments, they raise privacy concerns.

Enduring questions over which part of the brain helps produce that feeling of being 'awake' have been answered, thanks to stunningly detailed new brain imagery. Researchers' new high-resolution brain scans allowed them to see brain connections at a granular 'submillimeter' level — meaning down to...