While the exact causes of neurodegenerative brain diseases like Alzheimer’s and dementia are still largely unknown, researchers have been able to identify a key characteristic in affected brains: reduced blood flow. Building upon this foundational understanding, a team at Penn State recently found that a rare neuron that is extremely vulnerable to anxiety-induced stress appears to be responsible for regulating blood flow and coordinating neural activity in mice.

The researchers found that eliminating type-one nNOS neurons—which make up less than 1% of the brain’s 80 billion neurons and die off when exposed to too much stress—resulted in a drop in both blood flow and electrical activity in mice’s brains, demonstrating the impact this neuron type has on the proper brain functions of animals, including humans.

The research appears in eLife.