New research shows how brain cells work together to process touch with remarkable speed and precision. The brain’s ability to detect and respond to even the faintest sensory signals depends on a finely tuned partnership between the structure of neurons, the timing of surrounding brain activity, and the electrical properties of the cells themselves. The researchers found that these factors work together to allow groups of neurons to transmit information with extraordinary speed and precision, helping explain how the brain can process touch and other sensory input almost instantly, despite the constant “noise” of ongoing brain activity.

Researchers have uncovered how the brain is able to detect and process tiny sensory signals with astonishing accuracy — even when those signals are buried in the brain’s constant internal activity.

The study by Dr. Omer Revah and Prof. Michael J. Gutnick from the Hebrew University of Jerusalem, in collaboration with Prof. Fred Wolf and Dr. Andreas Neef from the Max Planck Institutes in Germany, was published in PLOS Biology. The findings shed new light on how groups of brain cells cooperate to rapidly transmit information, helping explain one of neuroscience’s biggest mysteries: how the brain makes sense of the world in real time.

The researchers discovered that the physical shape of neurons, the timing of background brain activity, and specific electrical properties of the cells all work together to make sensory processing fast and reliable.

“We found that the brain carefully balances several different features of neurons so they can respond extremely quickly to sensory input,” author of the study said. “Even very small signals can be detected and passed on with millisecond precision.”
The team found that although some neurons involved in sensory processing are unusually small, something that would normally limit their performance, the brain compensates by using slower, more coordinated background activity. This allows large groups of neurons to amplify weak incoming signals.

Remarkably, the researchers showed that the activity triggered by a single incoming sensory signal can be reliably detected by hundreds of neurons working together.

The study also identified an important role for potassium channels, tiny molecular “gates” that control electrical activity in brain cells. Because these channels are influenced by chemicals linked to attention and alertness, the findings suggest that the brain’s ability to process sensory information may change depending on a person’s mental state.

“This study helps explain how the brain stays both sensitive and efficient,” the authors added. “The brain is constantly active, yet it can still pick out the faintest sensory events almost instantly.”

The findings could eventually help scientists better understand neurological conditions that affect sensory processing, attention, or brain excitability.