CNS 2024 Q&A with Ella Striem-Amit
For the last two decades, Ella Striem-Amit has been searching for answers to some of neuroscience’s deepest questions: How does the human brain develop in individuals and what happens when something is missing? Working with people born without hands, sight, or hearing has given her and her team new insights into the compensatory mechanisms the brain uses to help enable people to live their lives fully when sensorimotor deprived.
“The brain is absolutely cool,” says Striem-Amit, a cognitive neuroscientist at Georgetown University and co-recipient of the CNS 2024 Young Investigator Award. “Working with and studying these types of populations is formative in seeing what humans can do and how the brain can support that. And it also can also lead to rehabilitation solutions.”
I spoke with Striem-Amit about her work with these populations, how she got started in her research, how the work might translate to treatments, future directions for cognitive neuroscience, and what she is most looking forward to at the CNS annual meeting this April in Toronto.
CNS: How did you first become interested in cognitive neuroscience?
Striem-Amit: Somewhere randomly at age 15, when I was trying to decide what I wanted to be when I grew up, I was reading a little bit of philosophy and I ran into Descartes’ Error by Damasio. It led me down the rabbit hole of cognitive neuroscience, and that’s when I decided to be a neuroscientist. Following my military service [in Israel], I did exactly that.
CNS: What led you to specifically study motor and sensory deprivation?
Striem-Amit: When I was an undergrad [at the Hebrew University of Jerusalem], I was looking for a lab for doing my honors thesis. And got into Ehud Zohary’s lab, where I started working on blindness before my graduate work. We were looking at a big, curious question that I haven’t really left and continued chasing them in my graduate work with Amir Amedi, followed by my postdoc with Alfonso Caramazza: How does the brain develop into what we have as adults? It’s such complex machinery, and what happens if you take something out? How does the brain develop in the absence of a certain type of experience?
CNS: What excites you about this general line of thinking?
Striem-Amit: It’s a classical nature/nurture question. But instead of versus you look at the relative contribution. There are then many more questions about the brain’s capacity for plasticity. And about what the actual functions are that these brain regions are organized for? For example, the minute we say that, a hand action can be performed by the foot and it would engage the same brain region, we’re saying that the focus of this region isn’t controlling a specific body part; it’s controlling a specific action. So the representation shifts from being low-level motor control to something that’s way more abstract, that can invariably generalize across different body parts.
CNS: In your research, you get to work across diverse populations, such as blind people and people born without hands. What has that been like?
Striem-Amit: It’s fascinating. By the time I meet my participants, they are fully functional adults. They have figured out how to deal with things that most of us would consider disabilities, but they are just differently abled; they can perform just about anything that we do. Just watch a movie of a person doing something with their foot who does not have hands. It’s incredible. They have it all figured out. One of them once told me that the only challenge is holding their coffee while they walk. So I have the privilege to meet these people who figured out how to do all these things in a very different way. And they participate in studies because they want science to benefit. Part of it is curiosity to see their own brains and how they are able to compensate, but I think they enjoy being able to contribute to science, and I am really grateful for their collaboration.
CNS: Of your and your team’s work to date, what is most exciting and significant to you?
Striem-Amit: So it’s hard to pick your favorite child, but I really think that my lab’s work on individual differences is exciting. I didn’t expect these findings would be this robust. I started looking in this area because I was confused about the role of the early visual cortex in blindness. At the group level, it really looks like the visual cortex is responsive to anything and everything, which, as a systems neuroscientist and as a cognitive neuroscientist, makes no sense. I’ve been trying to understand it throughout my career, for some 20 years now. And I still don’t have an answer. The only way I could start to make any sense of it was that each individual is driving this part of their brain for something slightly different. And at the group level, they all drive it enough in all of those aspects to drive a group result. But in fact, each of them has a different core preference for this bit of cortex. And then we went down that rabbit hole, which ended up showing that there’s differential conductivity for these different people, that it’s stable over a couple of years, and that individual differences are expanded through plasticity. So, plasticity generates more individual differences.
CNS: Can you talk about the translational aspects of this work?
Striem-Amit: I want to be very clear that these applications are in the future. My work is very much basic research, but I believe it does provide insight and potential outlooks for translational aspects. And that comes in two flavors, if you will, for both those without hands and for the blind.
The first is about handlessness. Current prosthetics are very simple devices that are controlled at a low level, like you open or close something like a claw. But it’s different when we perform our actions in everyday life. For example, reaching out for my cup, I never have to think how wide my digits have to be; I never have to think about how to apply enough force to grasp it so it doesn’t slip but not so much that it breaks. Our motor control manifests at a higher level of representation. We are aware of the higher level goals and action types of commands that we provide cascade down to motor hierarchy, all the way to motor neurons that can direct the muscles themselves. So if we can capture representation of that higher level of control, that is a way more natural way of controlling prosthetics. The goal of this entire research line beyond mapping how actions are represented in the brain, and the cognitive hierarchy, is to link it back to this translational goal: to read out the action planning and action in real time with EEG or something applicable in daily life, so we can then link it to a prosthetic with higher level commands.
CNS: What about the translational aspect you mentioned for the blind?
Striem-Amit: For that aspect, it’s not just about the blind; it’s about individual differences more broadly. The question is: How do individual differences arise neurologically and how much individual differences can there be in brain plasticity? We’ve shown that there are meaningful individual differences in how the visual cortex of people born blind is, and we’re trying to show that similar principles are found in deafness. The idea is that if different blind individuals, either through what they inherited or through their compensatory experience, have visual cortex that is driven through different senses, like audition or touch, that can tell us something about what compensatory tools would be most beneficial for them. That can inform, for example, more invasive sight restoration types approaches, such as retinal prostheses or even gene therapy. Some individuals may have rewired their brains in ways that make them more or less receptive to certain approaches, so our work might one day be able to guide these personalized decisions.
CNS: What do you most want cognitive neuroscientists to know about your work?
Striem-Amit: I think there is a lot of focus these days on big data, which is very appropriate for answering a lot of questions but is the wrong approach to answer other kinds of questions. For studying unique populations like in my work, deep data allows us to characterize individuals with deeper samples of behavior, imaging, etc. Cognitive neuroscience emerged from case studies, those classical lesion cases that gave us what we know about different brain parts and different functions, but there is less support for this type of work these days. I believe that a lot of insight really comes from diving deep down and looking at each participant’s own individual uniqueness.
I also think there’s a lot of work to be done with existing technologies, especially temporal tools. There’s been a lot of work on blindness, deafness, and plasticity over the last few decades. I really am standing on the shoulders of giants here. But I think we are missing some key insights about the temporal domain that I think a lot of other groups are doing. And I think that looking at all of this through an individual participant lens would also be very beneficial.
CNS: What are you most looking forward to at CNS 2024 in Toronto?
Striem-Amit: I love this community. I’ve been fortunate to work with a lot of great mentors, mentees, and collaborators, and it will be great to connect with some of them at the conference.
-Lisa M.P. Munoz
