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Laura Grafe, an assistant professor of psychology at Bryn Mawr, studies sex differences in stress and sleep in rodents. When the pandemic shut down her lab and made these studies, Grafe shifted her work to humans, using an online questionnaire to examine how the stress of COVID was affecting sleep.

Can you summarize your main research areas?

The main goal of my research is to understand how stress affects the brain. I'm particularly interested in how that could lead to changes in behavior that are relevant to mental health—things like cognitive impairment and sleep deficits after stress. I'm interested in figuring out what goes on in the brain to cause those things and how those things change. I'm also interested in individual differences in susceptibility to stress and different coping strategies that people use.

One of the main focuses in my lab is sex differences. I study rodents, so I’m trying to understand how male and female rats respond differently to stressors. My research is primarily conducted in rats because they closely resemble humans in many aspects of physiology and brain function and behavior. I can also perform a lot of mechanistic studies to determine how stress affects the brain. I can modulate a very specific neurotransmitter in a very specific brain region and observe how that changes cognitive function in the rodents. And you're often not able to do these types of things in humans.

How did you pivot when the pandemic started?

I've always been interested in translating my research about stress in the brain from rodents to humans, but until before the pandemic I never really got the chance to. When the lab shut down, it gave me time to sit back and think about how I would translate this to humans. It was a unique opportunity to study the effect of this common stressor on humans.

I began to think creatively about how I could ask questions about stress and coping and sleep in humans remotely, since we couldn't really do anything hands on. These topics mirror what I do in the lab with the rodents—understanding how stress can change coping and sleep—so I was excited to try to figure this out and ask these questions in humans, even if I had to do it remotely. I decided to launch an online questionnaire-based study about how people are dealing with stress and coping and sleep during the pandemic.

Did you collaborate with other Bryn Mawr faculty?

I collaborated with the postdoctoral fellow in my lab, Andrew Garjiulo, and also another colleague in the psychology department, Laurel Peterson. She was essential as a collaborator because she had expertise in doing these questionnaire-based studies and she also has expertise in higher level statistical analysis, which is really important in studies where you have a lot of variables that you can't control for.

How did you carry out the study?

We used an online platform based out of the U.K. that connects people with researchers that are willing to pay them to take these questionnaires. You can get good data because people are motivated to answer the questions truthfully and finish all of the questions. We recruited 400 participants who were currently living in the U.S. and formed a representative sample of the U.S.

What was the question you wanted to answer?

We were interested in understanding stress, coping and sleep during the pandemic because previous research had shown that in other disease outbreaks there's high stress levels and sleep impairments that can lead to psychiatric disorders. So, we wanted to understand how stress, as well as protective factors like coping and resilience, could affect sleep quality. We also wanted to know whether the amount of stress that someone is feeling is associated with their sleep quality and whether particular types of coping strategies affect sleep quality?

We also wanted to know if there were gender differences, because that's something that I look for in rodents. In non-pandemic conditions there are gender disparities in sleep. Typically, women report worse sleep quality than men, so we wanted to know if this was true during the pandemic as well.

What did you find?

Basically, what we found was that resilience and coping during the pandemic were more important in predicting sleep quality than stress or local infection rates. Based on people's zip codes, we were able to figure out how many cases of COVID 19 there were in particular areas of the U.S. and we found that the infection rates and the stress actually didn't tell us much about how people were sleeping; it was how they responded to the stress. What was important in predicting how well they slept were their types of coping strategies and their general resilience.

What kinds of coping strategies were helpful?

The most effective types of coping strategies are grouped under what we call greater primary control coping. That includes things like problem solving and emotion regulation. Those were associated with better sleep quality. Things that were associated with poor sleep quality included rumination and physiological arousal. We asked people if they felt they were sweating more, if their heart rates increased, things like that, when they thought about the pandemic. And those who said that they did feel those things tended to have worse sleep.

Did you still find the gender difference?

We did. We found that women had worse sleep quality during the pandemic than men, which is in line with what's been shown in non-pandemic research.

Why do you think that’s the case?

We don't know why. We have some ideas and there are insights from rodent models that suggest that things like estrogen or progesterone might drive sex difference in response to sleep, but I think there's also a lot more to consider when you're thinking about humans beyond the biological aspects. We should continue to think about things like child rearing and care taking responsibilities, sexism, and other sorts of things that might play a role in gender disparities in humans.

Is your lab back to normal now? And what are next steps for the research?

This past summer, I had a few undergrads in the lab and we're running both rodent studies and prepping for our next move with human studies. My goal for the human aspect of the research is to gather more objective measures of stress and sleep in humans. We have Fitbits in the lab that we're thinking about using to track people's activity and heart rate to give us some more physiological indicators of their stress and their sleep.

I'm also interested in learning more about how changes in hormones like estrogen impact stress, coping, and sleep. I just wrote an IRB protocol to launch a study that will examine how the menstrual cycle affects stress, coping and sleep in women and, if approved, this will be conducted with Bryn Mawr students.