Neurons get the beat and keep it going in drumrolls -- ScienceDaily
The researchers recorded the activities of individual neurons in the hippocampus, which is located in the lower center of the brain, with a robotic device called a patch clamp. It's a hollow glass needle one micron in diameter that latches onto a single neuron via suction and measures its electrical activity.
The researchers observed electrical rumblings, symbolized here by a drumroll. And they observed spikes, symbolized here by a cymbal crash.
Though the pattern of rumblings wasn't uniform, it rose and fell like a drumroll undulating between softer and louder volumes. Spikes occurred much more rarely than drumbeats, but with notable timing.
"The spikes repeated in the same spots with high precision, so they weren't just random," Singer said. "They came around the peaks of rumblings, not always right on top of a peak but within a hair of it."
It would be like a cymbal crash hitting not every time, but every few times the undulating drumroll topped a volume peak. And the drumroll-cymbal-crash patterns sustained themselves for surprisingly long periods.
"The time periods of activity that was structured like this were much longer than we expected," Singer said. "People have shown sustained periods of signaling like this for 100 to 300 milliseconds before, but this appears to be the first time it's been seen for 900 milliseconds (nearly a full second), and it may go on even longer."