New Research on Why Humans Are So Much Smarter Than Other Species

Humans are the most intelligent living organisms on earth. We have the ability to think and react to various situations, while animals do not. But why is that?
human brain

The notion of human superiority should have disappeared when Darwin’s theory of evolution appeared. However, it has been difficult to comprehend the full ramifications of what he said. And all creatures have successfully adapted to their respective environments in their unique ways. Intelligence in humans is merely one of many survival strategies.

Humans are unrivaled in terms of cognition. After all, no other species has ever launched probes to other planets and developed life-saving vaccines. The subject of how information is processed in the human brain to make this feasible has piqued everyone’s interest, yet no definitive answers exist.

While our understanding of how the brain works have evolved over time, the human brain has been characterized by present theoretical models as a “distributed information-processing system.” It means that human brains have various components intimately networked through the brain’s wiring. To communicate with each other, regions need a system of input and output signals to exchange information. But this is merely a small portion of a larger picture.


According to a recent study published in Nature Neuroscience, the researchers showed that there isn’t just one type of information processing in the brain – this is based on evidence from several species and multiple neuroscientific disciplines.

The research study

Humans and other primates process information differently, which may explain why our species’ cognitive abilities are superior. To examine how the brain processes information, the researchers borrowed principles from what’s known as the mathematical framework of information theory—the study of measuring, storing, and exchanging digital information – which is critical to technology like the internet and artificial intelligence. The researchers discovered that various brain regions interact with one another using different ways.

Insula of human and cynomolgus macaque monkey
Insula of human and cynomolgus macaque monkey by Henry C. Evrard. Licensed under CC BY 4.0

Some brain regions communicate with other areas in a stereotypical approach, using input and output. This guarantees that signals are sent consistently and reliably, especially for sections dedicated to sensory and motor activities, such as processing vision, sound, and movement.


Consider the eyes, which send messages to the back of the brain to be processed. Most information sent will be duplicated, with each eye providing its copy. In other words, half of this data is unnecessary, and this type of input-output data processing is termed “redundant.” Redundancy ensures durability and reliability, so we can see with only one eye, which is essential for survival.

The connections between these brain regions are so important that they are anatomically hard-wired in the brain, similar to a landline telephone. But not all information provided by the eyes is redundant. By combining information from both eyes, the brains can ultimately process distance and depth between objects, which is the basis for many kinds of 3D glasses at the cinema.

The instance above shows a fundamentally different manner of processing information, one that is more than the sum of its parts. When complex signals from different brain networks are integrated, this type of information processing is called “synergistic.”


Synergistic processing is ubiquitous in brain regions that enable various more complex cognitive processes, such as learning, numerical and social cognition, attention, learning, and working memory. Synergistic processing is not genetically programmed because it can adapt to our experiences and connect different networks in new ways. This makes it easier to combine information.

1024px Primate skull series with legend
Primate skull series by Christopher Walsh under CC BY 2.5

The front and middle of the cortex (the brain’s outer layer) are particularly synergistic, integrating different sources of information from all over the brain. As a result, they are more extensively and effectively connected to the rest of the brain than the areas that deal with main sensory and movement information. Synapses, the microscopic connections that allow nerve cells to communicate, are abundant in high-synergy zones that assist information integration.

“We’re dealing with an unanticipated, huge, quick, and reversible adaptation mechanism,” says Ivan Rodriguez, one of the study’s co-corresponding authors. This research shows that olfactory neurons are not merely sensors transitioning from a resting to a stimulated state, but rather their identity is constantly evolving, not only in response to the expressed receptor but also in response to previous experiences.


Human learning ability

Comparative psychologists have spent decades trying to figure out how to rank the learning capacity of various species on a single scale. People questioned if fish were smarter than birds using animal intelligence testing. It took Nobel Laureates Konrad Lorenz, Niko Tinbergen, and Karl von Frisch to establish the new science of ethology, which demonstrated that each species has the talents required for its unique lifestyle and that these abilities could not be ordered on a universal scale.

Human smartness isn’t superior to others. This classifies “learning” as one of the “more complicated cognitive activities” rather than the basic dynamic of the more complex cognitive functions, determining what populates memory and, obviously, everything about numerical and social cognition.

Is it synergy that distinguishes us?

It’s difficult not to be charmed by what makes us unique as humans. We sought to see if humans and other primates with close evolutionary relatives have differing abilities to acquire and create information through intricate networks across the brain. The researchers considered “brain imaging data” and “genetic analyses” of different species to find answers to the question. They found that synergistic interactions account for a higher proportion of overall information flow in the human brain than in the brains of macaque monkeys. In contrast, the brains of both species are the same in how much they depend on redundant information.


Prefrontal cortex study

The assessment of the prefrontal cortex – an area in the front of the brain that supports more advanced cognitive functioning – showed that redundant information processing is more prevalent in this region in macaques, while it is a synergy-heavy area in humans. The prefrontal cortex was also found to have undergone significant expansion with evolution. When the researchers examined data from chimpanzee brains, they found that the more a region of the human brain had expanded during evolution in size relative to its counterpart in the chimp, the more this region depend on synergy.

Prefrontal cortex left lateral view
The prefrontal cortex (left) – lateral view by Polygon data were generated by Database Center for Life Science(DBCLS). Licensed under CC BY-SA 2.1 JP

Genetic analyses

The genetic analyses from human donors showed that brain regions associated with processing synergistic information are more likely to express genes that are distinctively human and related to brain function and development, such as intelligence.

What the scientists were able to demonstrate

The research ultimately elucidates how the human brain balances the need for both dependability and information integration. Essentially, the framework developed hopes to provide vital new insights into a wide range of neuroscientific queries, from general cognition to disorders.



The researchers concluded that an additional human brain tissue obtained during evolution might be predominantly dedicated to synergy. It is sequentially tempting to believe that the benefits of higher synergy may partly describe our species’ enhanced cognitive capacities. Synergy may add a vital piece to the puzzle of human brain evolution that has previously been absent.