Scientists spot brain cells hanging out together for the first time

TAIPEI, Sept. 26, 2024 /PRNewswire/ -- Networking and communal behavior are traits shared even by neurons. Research has revealed that brain neuron cells exhibit patterns akin to friends spending time in each other's company and collaborating.

A study released in Neuron by assistant professors Tsai-Wen Chen and Bei-Jung Lin from National Yang Ming Chiao Tung University (NYCU) in Taiwan uncovered new insights into parvalbumin interneurons (PV cells). These cells are a major group among the brain's inhibitory neurons, crucial for governing brain rhythms. Using advanced microscopes, they observed PV cells engaging in group dynamics, firing together like dancers. Not only do they active simultaneously in a coordinated manner, but they also seem to have preferred "buddies" they like to hang out with.

Interneurons are like the hidden gems of the brain, rarely seen and hard to study. In the past, scientists had to rely on implanted electrodes, catching only sporadic glimpses of their electrical signals. "It was like searching for a needle in a haystack," Lin explained. However, the research team made a breakthrough with a new voltage imaging technique combined with fluorescent proteins. This allowed them to record up to 26 interneurons in a single experiment, giving them an unprecedented look into how these cells interact.

The team discovered that interneurons do not just active randomly. They love to synchronize their activity, generating action potentials together like friends having a group chat. These cells actively seek out and connect with their buddies to transmit signals, creating a lively neural network.

"Imagine interneurons as instrumentalists in a symphony, all playing in harmony under the conductor's baton," said Chen. Interneurons play a key role in the formation of brain waves. Brain waves are generated by potential changes at neuron synapses, needing a group of resonating cells to be detected from the scalp. Interestingly, even when these cells do not reach the threshold to produce action potentials, their "grouping" activity can still be observed under the microscope, showing their natural inclination to work together.

To tackle the challenge of directly observing voltage with microscopes, Chen and Lin's research team partnered with international collaborators to create voltage-sensitive fluorescent proteins. They used adenoviruses as carriers to make neurons glow after infection. To capture the fleeting neuronal pulses, the team designed a high-speed imaging system that can snap 2,000 images per second. The technology is available at NYCU, providing an extraordinary real-time glimpse into the dance of the cells.

With these cutting-edge technologies, scientists can now watch interneurons in living animals as they work together in real time. The study reveals the complex teamwork of interneurons, offering vital insights into the mysteries of brain function.

Photo: https://reurl.cc/Wx6KOD
Research Paper: https://www.science.org/doi/10.1126/science.aav6416

SOURCE National Yang Ming Chiao Tung University