Smartphones or the human brain: Which processes information faster?

The human brain, often hailed as nature’s most powerful computer, is surprisingly slow when it comes to handling information. While our senses gather a mountain of data every second, our actual thoughts crawl along at a far slower pace.

Every moment, your body absorbs around a billion bits of sensory data—from sights and sounds to touch and temperature. But only about 10 of those bits make it into your conscious mind each second. That’s less than what a pocket calculator processes, and light-years behind the speed of digital devices.

A recent study led by Jieyu Zheng at the California Institute of Technology (Caltech) dove deep into this mystery. By applying information theory to decades of research on human cognition, the team examined how data flows from the senses to conscious awareness.

They discovered a striking bottleneck. The body’s peripheral nervous system works with incredible speed, collecting sensory input from the environment almost instantly. Yet the brain reduces this torrent to just 10 bits per second—barely enough to form a complete sentence in that time.

“This is an extremely low number,” said Markus Meister, a senior researcher on the study. “Every moment, we extract just 10 bits from the trillion that our senses take in, using those 10 to perceive the world and make decisions.”

For context, a typical Wi-Fi connection transfers around 50 million bits per second. Even individual neurons are capable of transmitting far more than 10 bits each second. Yet collectively, the brain chooses to run at this low speed, revealing a puzzling contrast between its architecture and its output.

That raises a big question: why does the brain, unlike the sensory systems feeding it, handle only one thought at a time? With its 85 billion neurons, it could, in theory, juggle far more. But instead, it filters reality into a narrow stream, guiding your perception—and every decision—through a surprisingly tiny window.

Researchers speculate that evolutionary history might provide some answers. The earliest nervous systems likely evolved to support navigation, enabling organisms to move toward food and away from predators. This evolutionary path could explain why modern human thought resembles a form of navigation—moving through a conceptual space one idea at a time.

In their paper, Zheng and Meister suggest that this sequential processing is embedded in the brain's architecture. "Human thinking can be seen as a form of navigation through a space of abstract concepts," they write. The brain’s preference for linear thought aligns with its historical role in navigating physical spaces.

Moreover, the study highlights that humans evolved in relatively slow-paced environments, where processing 10 bits per second sufficed for survival. While modern technology bombards us with information, the brain’s processing speed remains rooted in these evolutionary foundations.

This slow speed of thought has significant implications for neuroscience and future technology. For instance, tech visionaries have proposed direct brain-computer interfaces to accelerate communication. However, the study’s findings suggest that such interfaces would still operate at the brain’s intrinsic limit of 10 bits per second.

This bottleneck might explain why human behavior, from playing chess to solving puzzles, involves deliberate, sequential steps. Even a chess player envisioning potential moves can only process one sequence at a time.

The brain’s inability to process multiple trains of thought in parallel highlights a stark contrast with its sensory systems, which manage thousands of inputs simultaneously.

Markus Meister emphasized the need for future research to address these paradoxes. Understanding why the brain filters vast amounts of sensory data into such a limited stream of conscious thought could unlock new insights into its design and function.

While the brain’s slow thought speed might seem like a limitation, it’s essential to consider the context. "Our ancestors chose an ecological niche where the world is slow enough to make survival possible," Zheng and Meister wrote. In most scenarios, the environment changes gradually, and the brain’s processing speed is adequate.

Nonetheless, the discrepancy between the sensory system’s input and the brain’s output suggests room for further exploration. Could advances in neuroscience and technology help bridge this gap? Or are these limits inherent to the brain’s structure and evolutionary design? Such questions remain open for investigation.

As scientists delve deeper into these mysteries, this research underscores the brain’s complexity. It also invites a reevaluation of assumptions about its capabilities and constraints, offering new perspectives on how we interact with both natural and artificial systems.

Note: Materials provided above by The Brighter Side of News. Content may be edited for style and length.

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