Dr. Marlene Cohen
Professor Neuroscience, University of Pittsburgh
Postdoctoral Fellow Harvard Medical School
Ph.D. Neuroscience, Stanford University
As an undergraduate math major, Dr. Marlene Cohen attended a lecture that left her smitten with the brain. She sat captivated as Dr. Matt Wilson impersonated place cells in the hippocampus firing a barrage of action potentials in different locations as he roamed around the room. This engaging demonstration of how place cells encode spatial information, and the broader idea that there are cells in our brains that encode something relevant for behavior, enthralled Marlene. She also happened to be in need of a job, so she “begged” Matt for a research position in his lab (and he agreed). This was just the beginning of Marlene’s journey to understand how neural activity gives rise to behavior – a question that she continues to pursue in her own lab, particularly in the context of visual attention.
Her job in the Wilson lab and some additional neuroscience courses solidified her newfound interest in the brain, and Marlene decided to apply to neuroscience PhD programs. She describes herself as feeling like a “fish out of water” when she arrived at Stanford University and began wading through her first neurobiology courses. Since she had majored in math in college and hadn’t taken a biology course since high school, some of the more molecular courses presented a steep learning curve, with countless terms she wasn’t familiar with. Building on her initial interests developed in Matt Wilson’s lab, she joined the laboratory of Dr. Bill Newsome, who studies the neural basis of vision and visual cognition. Marlene dove in enthusiastically, learning as much as she could from her fellow lab members. She became especially interested in understanding how our brains can use the same [visual] input to make different decisions in different contexts – for instance, whether or not to eat a chocolate chip cookie if it’s sitting on the kitchen counter versus in the aisle of a grocery store. To test this, she designed a set of tasks in which identical stimuli prompted different behavioral responses. She recorded from two neurons simultaneously – a major advance at the time! – while animal subjects performed these tasks. From these experiments, she found that identical visual stimuli presented in different contexts resulted in different degrees of correlation between their activity, a measurement referred to as “noise correlations”.
Marlene considered many possible next steps after finishing her PhD, from industry or consulting to studying dolphin cognition in Hawaii. Ultimately, she decided that she was particularly attracted to the intellectual freedom afforded by a career in academia. She joined the lab of Dr. John Maunsell as a postdoc with the goal of recording from even larger populations of neurons than she had in her PhD to gain insight into the neural basis of visual attention. She wondered: what changes are taking place in the brain that allow you to see things better when you specifically pay attention to them? She found that in conditions when you’re paying close attention to a particular feature of a cue and thus seeing it very clearly, the “noisy” fluctuations in activity of individual neurons among a population become more independent from one another - in other words, noise correlations decrease.
This discovery and fundamental approach of linking aspects of population activity to aspects of flexible behavior drove the inception of the Cohen Lab at the University of Pittsburgh. Since then, while keeping to the same general, overarching theme, her lab’s work has expanded in many directions beyond those she had anticipated. They have begun to explore neural population changes in more naturalistic, flexible behaviors in both humans and animal models, utilizing novel computational models and analyses. Her lab has also begun pursuing more translational work, such as exploring how drugs that treat disorders of attention affect neural populations, and even how early changes to visual attention could be early indicators of Alzheimer's disease. Marlene sees tremendous promise and mutual benefit in merging basic science with more clinically-oriented approaches to neuroscience research, a direction that she is excited to further pursue as she prepares to move her lab to the University of Chicago.
While Marlene has already achieved considerable stature in her field as a mid-career neuroscientist, earlier in her journey, she sometimes struggled to see herself as a “real scientist”. Many of the eminent neuroscientists she looked up to had big personalities that “filled the room”, and that didn’t quite feel like her. Moreover, she heard bits of advice about choosing a research project that was all she ever wanted to think about, or that she should only pursue a career in science if she couldn’t imagine herself doing anything else. But those things didn’t resonate, either. Looking back, she reflects, “I am not - I never will be - a person who is hyper-focused on any one thing; I never will be somebody who fills the room…; and I’ve never had success pretending to be those things. Any success I’ve had has been in finding a way to do it my way.” Marlene finds fulfillment not only from her scientific pursuits, but also from being a mom and from her other varying interests. For instance, she is an avid musician; she plays multiple woodwind instruments in a variety of genres and is even trying to start a band with her kids! She considers her diversity of interests a strength; many of her best scientific ideas have come to her in moments when she was diverting herself in some other way, completely unplugged from her work. Thus, she advises young trainees to “find role models who have lives that kinda look like the life you might want,” who may or may not be the same as one’s scientific role models. Undoubtedly many young trainees will consider Marlene a role model, both for her scientific prowess as well as for her jubilant approach to life.
Find out more about Marlene and her lab’s research here.
Listen to Marlene’s full interview with Chiaki on January 22, 2022 below!
