Read the label of a prenatal vitamins bottle at a drugstore and chances are you’ll see, nudged between biotin and calcium, a nutrient called choline. You can thank Christina Williams for that.
Williams, who recently retired after 30 years as a professor Psychology & Neuroscience at Duke, has a long history of looking at how prenatal nutrient supplementation affects offspring memory.
“Choline is a very important nutrient,” said Williams, “but one that very few people know much about.”
Choline — an essential nutrient found in egg yolks, dairy products and other dietary staples — is a building block of the neurotransmitter acetylcholine, known for its role in helping the brain remember things. Intrigued by the role played by choline in brain development, Williams wanted to know what would happen if she gave mother rats extra choline in their diet. Williams suspected that the supplementation might have an impact on the babies’ memory. Her hypothesis was correct: Not only did the offspring of choline-supplemented moms have better memories when they were young adults, they also showed little age-related memory decline.
Williams’ research on choline supplementation for fetal brain development had a widespread impact on prenatal vitamins and memory research and gained interest from researchers studying Down Syndrome, Alzheimer's disease and food manufacturing.
Now, you can find choline in prenatal vitamins, cereals and children’s vitamins.
Williams, who spent 12 years as a professor at Barnard College of Columbia University prior to joining Duke, also did extensive research on sex differences in rat brains. When she was in college, many people were looking at how hormones influenced male and female behavior in rats, focusing on sex differences in reproductive and aggressive behaviors.
Williams decided to branch out and look at whether male and female rats thought differently.
She said that in humans, cultural and environmental factors make it difficult to drill down on what are actually sex differences. But not so with rats.
“In general, what we were seeing was that the male form was the ‘best’ form, and as a female scientist, this annoyed me,” said Williams. “I thought it would be important to look at whether hormone exposure early in development or in adulthood modified rats’ memory.”
Initially, Williams hoped there was no difference in how male and female rats’ memory, or that females would be smarter. She designed experiments where she manipulated the hormones that male and female rats were exposed to in early development, and looked at how that impacted their ability to remember multiple spatial locations. She found that females were significantly slower to master the multiple memory task than the males, but not because they had difficulty holding locations in memory. Females used many environmental cues, while males relied on only a few.
“If you took a cue out of the environment, the males were confused, because they only learned a couple of things,” said Williams. But when she removed the same cue from the females, they relied on other cues they had learned. “It took females longer to master the task, but they were more resilient when the environment shifted.” Importantly, this difference in the content of male and female memory was caused by what hormones they had been exposed to early in development.
This line of research laid the foundation for future research in memory, hormones, and aging. “It changed people's thinking about male-female differences in brain function,” she said. “And I’m extremely proud of it.”
Williams has loved teaching and interacting with undergraduate students during her time at Duke. She said that being alongside them as they learn about the science of the brain has been a highlight, and she is always impressed with their ability to ask novel questions.
“Duke students are so smart, so interesting,” she said. “They’re a real amalgam of different backgrounds and interests and skills. I’m always so impressed that they are so very multi-talented”
“For decades, Christina Williams has been the principal advocate for undergraduate education in Neuroscience at Duke,” said her colleague, Len White. “Without her vision, academic acumen, passion and leadership, Trinity College would not have a world-class educational program for undergraduates in the field of neuroscience, as it does today.”
Starting Duke’s Neuroscience major is one of Williams’ career highlights. After several attempts and being told the major was too “boutique”, Williams and her colleagues were successful in getting it approved. In the first year alone, 11 students managed to get all their requirements for the new major fulfilled in time because they wanted to be neuroscience majors. It is now one of the more sought-after degrees at Duke.
“I’ve had the pleasure of watching the major grow from a handful to well over 100 students a year before I stepped down as the Director of Undergraduate Studies,” she said.
After 30 years at Duke, Williams’ impact on the university and her field cannot be understated.
“The ongoing success of the Neuroscience program at Duke to this day has everything to do with the foundation she built through her visionary leadership, her commitment to rigor in science and in education, and her steady advocacy for the program, its faculty and its students over the course of her Duke career,” said White.
So, what will Williams miss most? “I’ll miss the little ‘aha’ moments of interacting with students and people in my lab,” Williams said. “The undergraduate who didn't know anything about how the brain works and suddenly gets some complicated process, or the graduate student running into my office to tell me about some new data they just collected. Or a postdoc writing me a note saying they just found an academic position.”
She is, however, looking forward to the freedom and flexibility that comes with not having to manage an animal lab.
“It’s like running a small business,” she said. “You’re never off the clock. You have to manage employees, payroll, purchasing, and you have to be available when things go wrong. This along with teaching, mentoring, grant and paper writing and reviewing.”
She’ll have no shortage of things to keep her busy, though. “I want to enjoy some extended travel to places I’ve not visited while attending Neuroscience conferences. I’ve already planned a trip to India and Nepal and hope to get to Africa soon” she said. “I want to learn how to speak Spanish, do some community volunteering and I’m a huge theater fan so I have plans to be in New York and London a lot. And of course, as many people know, my dog Riley keeps me active, too.”