Speed of human thought lags far behind your internet connection, study finds

In our digital age, few things are more irritating than a slow internet connection. Your web browser starts to lag. On video calls, the faces of your friends turn to frozen masks. When the flow of information dries up, it can feel as if we are cut off from the world. Engineers measure this flow in bits per second. Streaming an HD video takes about 25 million bps. The download rate in a typical American home is about 262 million bps.
Now researchers have estimated the speed of information flow in the human brain: just 10 bps. They titled their study, published this month in the journal Neuron, “The unbearable slowness of being.” “It’s a bit of a counterweight to the endless hyperbole about how incredibly complex and powerful the human brain is,” said Markus Meister, a neuroscientist at the California Institute of Technology and an author of the study. “If you actually try to put numbers to it, we are incredibly slow.”
Meister got the idea for the study while teaching an introductory neuroscience class. He wanted to give his students so me basic numbers about the brain. But no one had pinned down the rate at which information flows through the nervous system. Meister realized that he could estimate that flow by looking at how quickly people carry out certain tasks. To type, for example, we look at a word, recognise each letter and then sort out the sequence of keys to press. As we type, information flows into our eyes, through our brains and into the muscles of our fingers. The higher the flow rate, the faster we can type.
In 2018, a team of researchers in Finland analysed 136 million keystrokes made by 168,000 volunteers. They found that, on average, people typed 51 words a minute. A small fraction typed 120 words a minute or more. Meister and his graduate student, Jieyu Zheng, used a branch of mathematics known as information theory to estimate the flow of information required to type. At 120 words a minute, the flow is only 10 bits a second.
“I was thinking, there must be faster behaviours,” Zheng recalled. She suspected that championship video game players might have a higher information flow when they are competing. Though gamers move their fingers quickly, they have fewer keys to choose from. So, when Zheng took a close look at the performance of gamers, she ended up with the same estimate: 10 bits per second.
Britton Sauerbrei, a neuroscientist who was not involved in the study, questioned whether Meister and Zheng had fully captured the flow of information in our nervous system. They left out the unconscious signals that our bodies use to stand, walk or recover from a trip. If those were included, “you’re going to end up with a vastly higher bit rate,” he said. But when it comes to conscious tasks and memories, he said: “I think their argument is pretty airtight.”