Dr. Denise Cai
Assistant Professor Department of Neuroscience, Icahn Schoool of Medicine at Mount Sinai
Postdoctoral Fellow University of California Los Angeles
PhD in Psychology and Behavioral Neuroscience University of California San Diego
As Dr. Denise Cai was interviewing for law schools, she couldn’t stop thinking or talking about the brain. For her undergraduate thesis project at UC San Diego, Denise had built a mathematical model for how attorneys make decisions about accepting certain cases. A pre-law student at the time, she was more focused on the judicial implications than the decision-making itself. However, as she was visiting law schools, she found her mind churning with thoughts not of court cases but of experiments, and her favorite interview conversations were those not about the law but about the brain. Denise realized that her heart was pointing her towards an entirely different career path, and so she rescinded her law school applications, deciding to apply to graduate school instead. Today, she designs creative experiments and thinks about the brain for a living as an Assistant Professor of Neuroscience at the Icahn School of Medicine at Mount Sinai. She has no regrets.
Because of her love for the beach as well as the brain, Denise returned to San Diego after her change in career plans, joining the Psychology graduate program at UCSD. While initially curious about language cognition, she became especially interested in learning and memory and their relationships to sleep during her master’s thesis. Thus, for her PhD work, she began working with Dr. Sara Mednick to explore the importance of REM sleep for creativity in humans. While she was excited about this project, there was a certain limitation to working with humans. She wanted to better understand what was going on “between the ears - I wanted to pry open that black box!” Her curiosity led her to establish a collaboration and co-advisorship with Drs. Stephan Anagnostaras and Michael Gorman to conduct more mechanistic studies in rodent animal models in parallel to her work with humans. This resulted in a uniquely collaborative thesis on the interplay between sleep and memory that bridged between human and animal models. It was also immensely productive, resulting in an astounding 11 papers (including four as a first-author) in three years!
Moving forward in her career, Denise wanted to continue her work on learning and memory but with a more translational perspective. This led her to work with Dr. Alcino Silva at UCLA for her postdoc, exploring the temporal relationship between memories. She made the exciting discovery that memories formed closer together in time can become linked; for instance, a mouse that is shocked in one environment and experiences a new environment shortly thereafter may come to have a fearful memory of both environments, but not of a third environment experienced multiple days later. Remarkably, this temporal linking is underlied by shared neural activity between different populations, or “ensembles”, of neurons in the hippocampus. In other words, ensembles that are activated when a mouse explores different environments are more similar when they occur closer together in time. This discovery has tremendous implications for understanding the neural effects of aging, as well as memory-related disorders like PTSD and Alzheimer’s. For instance, Denise also found that this temporal linking was impaired in older mice but could be rescued. Excitingly, Denise even collaborated with her PhD advisor to show that humans exhibit a similar behavioral effect of temporal linking, suggesting that her mouse work has real translational potential.
Today, in her own lab at Mount Sinai, Denise is continuing her work on how memories are stored in the brain. She is especially interested in understanding how memories accumulate across the lifetime and how the ability to access them is impacted in neurodegenerative and neuropsychiatric disorders and in old age. Denise hopes that this work will lead towards developing new therapies or interventions for improving memory in these disorders and in aging. In a new line of work in her lab, Denise is also circling back to some of her graduate work on sleep and looking at what role it might play in updating and changing memories. Moreover, starting during her postdoc and continuing into her own lab, Denise has been part of a collaborative effort that initially developed an affordable, open-source method for imaging neural activity in a freely moving and behaving mouse - the UCLA Miniscope. Thanks to the work of Denise and her collaborators in making the Miniscope widely available and accessible, this technology is now being used in hundreds of labs around the world.
While becoming a faculty member and starting her own lab has presented the exciting opportunity to assemble and cultivate her own team and research program, it has also led Denise to reflect upon some of the challenges she faced in her career, many of which pertain to gender bias. Looking back, Denise realizes how these biases - both explicit and implicit - often took their toll. Much of this realization has come from comparing her experiences to those of her husband, who she describes as her “wild-type littermate”; they have had very similar training and started their labs at the same time, yet she has seen stark differences in how they are assessed, from the way they give talks to their perceived "expertise" in grant applications. While in the course of her training, Denise used to internalize some of the comments and criticisms that she now sees were steeped in bias. This newfound awareness helps her be less concerned about the opinions of others as she moves forward in her career.
As much as Denise enjoys thinking about experiments to assess how the brain makes and stores memories, she says that what she loves most about her job - what has led her to and retained her in a scientific career - is the people. Her lab has the motto “TEAM: Together Everyone Achieves More”, and this applies not only to the culture for her own lab but also to her vision of open, collaborative science that extends beyond her lab. Her optimism and enthusiasm, her innovative thinking and her forward-looking perspective are just a few of the many attributes that make Denise a rising star in the field of neuroscience.
Find out more about the exciting research in Denise’s lab here.
Listen to Nancy’s interview with Denise on March 10th, 2020 below or wherever you get your podcasts!
