Staff Writer Meredith Wadman and host Sarah Crespi discuss what to expect from the two messenger RNA–based vaccines against COVID-19 that have recently released encouraging results from their phase III trials and the short-term side effects some recipients might see on the day of injection.

Sarah also talks with researcher Xing Chen, a project co-leader and postdoctoral scientist at the Netherlands Institute for Neuroscience, about using brain stimulation to restore vision. Researchers have known for about 70 years that electrical stimulation at certain points in the brain can lead to the appearance of a phosphene—a spot of light that appears not because there’s light there, but because of some other stimulation, like pressing on the eyeball. If electrical stimulation can make a little light appear, how about many lights? Can we think about phosphenes as pixels and draw a picture for the brain? How about a moving picture?