Meet the brilliant scientist who just got $625K for her work on a vital, overlooked part of the brain

On Sept. 29, the MacArthur Foundation announced the 24 recipients of its $625,000, no-strings-attached, five-year "genius" grants.

Of its seven fellows working in STEM fields, only one is a woman: neuroscientist Beth Stevens, PhD, who studies how brain cells communicate and how miscommunication can lead to disease.

She holds several positions: assistant neurology professor at Harvard Medical School, research associate at Boston Children’s Hospital, and institute member at the Broad Institute of MIT and Harvard.

Stevens' research focuses on understanding how glial cells (a.k.a. glia) interact with neurons to communicate with one another through synapses. Glia, though not as well-known as neurons, actually make up about half of the brain. That's why they caught Stevens' eye.

"I became fascinated by glia and the fact that we knew so little about a cell type that makes up more than half of the brain," Steven told the journal Neuron, in explaining how she came to focus on what was once a mostly overlooked area of neuroscience. "This set me on an exciting path that gets more interesting with every step."

They're like the "Pac-Men" of the brain, Stevens explains, because they can clear debris: the waste products of your brain doing its thing. This makes glia a crucial component in protecting against diseases like Alzheimer's and schizophrenia.

But glial cells actually play a huge role in early brain development, too — as important research from Stevens' lab has shown.

We are born with an abundance of synaptic connections, which is how brain cells talk to one another, Stevens explains, in a video from the MacArthur Foundation. Those connections decrease as we age. Glia carry out this pruning, acting a bit like gardeners by deciding which synapses to eliminate — and which ones to strengthen and keep.

Stevens' lab is trying to figure out how glia decide which synapses get to stick around, because their loss later in life can lead to cognitive impairment. "What's most striking about this [synapse loss] is that it's thought that [it] occurs years before you see signs of cognitive impairment or pathology," she says in the video. "That means it's critical that we understand how these synapses are lost. What makes synapses vulnerable?"

Understanding this pruning mechanism, she says, could lead to treatments for diseases that are related to it. The $625,000 grant will go toward tackling these big questions that might have taken 10 years to start answering, Stevens says.