This story appears in the October 2018 issue of National Geographic magazine.

Brains are in short supply. Neuroscientists need brain tissue of all types to study the diseases that affect more than 15 percent of people in the world. Enter Tish Hevel. In 2015, after Hevel’s father died from Lewy body dementia, her family wanted to offer his brain for research—but knew that it would take much more than an organ donor card. The experience inspired Hevel to create the Brain Donor Project “to raise awareness of the critical need” and make enrolling easier for would-be donors. Nearly two years in, more than 2,000 people have signed up.

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Busting myths about donating your brain

The organization that Tish Hevel created—online at braindonorproject.org—aims to simplify “the process of donating postmortem human brains for research,” she says, and dispel misconceptions about it. Here’s what you need to know.

1. Organ donor

If your driver’s license says you’re an organ donor, then congrats: You’ve done a noble thing. But not all your organs are included. Your heart, corneas, and pancreas might go to a lucky person, but your brain will stay with you unless you’ve made separate arrangements to donate it.

2. Healthy brains

What state your brain will be in when it’s donated may be a crapshoot, but the truth is, it matters only if certain conditions or infectious diseases are present. Science needs brains of all types, since a critical part of the research process is comparing diseased and healthy organs.

3. Open casket

You may fear that brain removal will cause discomfiting changes in appearance. It won’t; the brain is removed through an incision in the back of the head, and “it’s not disfiguring,” says Hevel.

4. The costs

In the United States, if you donate your brain to one of six National Institutes of Health brain banks, there’s no cost to the family for retrieving the brain after death, for the donation, or for storage.

5. The timing

Time is of the essence if you’ve donated your brain to science. Pathologists need to collect the brain within 24 hours of death, and they prefer to harvest the tissue as soon as possible. So be sure to tell your family about the choice you’ve made and how your wishes should be carried out.