If there is one field of study where researchers are constantly puzzled by what they find, it is the study of the human brain. According to a report from Discovery News, scientists at the Salk Institute for Biological Studies and the University of Texas – Austin have discovered that the human brain has ten times the memory capacity than once believed.

How did researchers arrive at this number? The team, led by Salk professor Terry Sejnowski, set out to create a 3-dimensional model of the basic building blocks of a rat’s memory center, the hippocampus, including dendrites, axons, and glial processes. The model was the size of a single cell, but it contained a big secret.

Researchers noticed that occasionally, a neuron would have two synapses reaching out to connect with another neuron, sending the same message twice.

Scientists found this strange, and they decided to investigate further. They found that the difference in size between the duplicating synapses was roughly eight percent. This hardly seemed significant at first. But when they plugged this size difference into algorithms that calculate how much information could potentially be saved in the brain, they realized just how big the brain’s storage center actually is.

Of all the synapses in the brain, sizes can vary by as much as a factor of 60. The majority of these synapses are small, but the discovery that they could vary by as little as 8 percent in size along such a great scale revealed that there are actually as many as 26 different types of synapses, instead of just a few.

According to Salk staff scientist Tom Bartol, We were amazed to find that the difference in the sizes of the pairs of synapses were very small, on average, only about eight percent different in size. No one thought it would be such a small difference. This was a curveball from nature.”

A press release from the Salk Institute for Biological Studies describing the recent breakthrough can be found here.