Neuroscience

As we move about in our daily lives, we tend to think that we navigate space in a linear way—but our brain does not always act in a linear manner. Professor Tatyana Sharpee, graduate student Huanqiu Zhang, and colleagues discovered that time spent exploring an environment causes neural representations to grow in surprising ways. Neurons in the hippocampus, essential for spatial navigation, memory, and planning, represent space in a manner that conforms to a nonlinear hyperbolic geometry—a three-dimensional expanse that grows outward exponentially (like the interior of an expanding hourglass). This discovery provides valuable methods for analyzing data on neurocognitive disorders involving learning and memory, such as Alzheimer’s disease.

Despite decades of research, Alzheimer’s disease remains a debilitating and eventually fatal dementia with no effective treatment options. Now, Professor Rusty Gage, graduate student Joseph Herdy, and colleagues have found that neurons from people with Alzheimer’s disease show deterioration and undergo a late-life stress process, called senescence. These neurons have a loss of functional activity, impaired metabolism, and increased brain inflammation. Additionally, the team discovered that targeting these deteriorating neurons with therapeutics could be an effective strategy for preventing or treating Alzheimer’s disease.