For centuries, various scholars from very different perspectives have tried to define intelligence and how do brains work. Over time, many questions have been asked about this concept, for example, the nature of intelligence – whether innate or acquired – which determines intelligence – a single general factor or a set of specific common capabilities, the role of intelligence in academic performance, whether there can be the many types of intelligence, etc.
How Do Brains Work and How to Define Intelligence
When we talk about general intelligence, we are talking about the intuitive ability of a person to make the right decisions and solve problems, not about their memory capacity or their abilities in a specific area.
The development of “multiple intelligences”: it has been affirmed for the first time that there is no single intelligence but that, depending on the human being, he has several bits of intelligence. More precisely, 8 types of intelligence are proposed (approximately, since the figure evolves). Each person would have greater development in some and less in others.
The development of “emotional intelligence“: where we start from the fact that there are more variables that influence the success of people; more precisely the emotions. This new intelligence, in broad outline, would help us to interact with ourselves and with others, by properly managing the emotional aspects, with all that it encompasses.
Intelligence has been proposed as a “capacity to adapt to the world” in its broadest form. One author also stated that intelligence was closely related to emotion, memory, creativity, optimism, and in a sense, mental health.
This new, more complex way of looking at intelligence has come to fight something: in research, it has been discovered that the intelligence quotient (IQ) predicts only a small part of a person’s success.
Today, it is recognized that human intelligence affects other aspects such as personal satisfaction or how human beings are related to each other.
But what are the neurological bases of the human brain? How do brains work? It is obviously for these questions that we will attempt to answer in this article. To tell the truth: “There is no single intelligence but, depending on the human being, he has several types of intelligence.”
I – Researchers Measure How Do Brains Work Directly in the Brain
Researchers at the University of Warwick, England, in a study published in Brain in July 2016, reveal that they directly measured intelligence in the human brain, developing new technologies for recording brain activity, and found that the more frequently the parts of the brain are interconnected, the higher the IQ and creativity of an individual.
In this study, scientists quantified the dynamic functions of the brain and identified how different parts of that organ interact with each other at different times. All this has been done to try to discover how our intellect works.
*** Differences in Variability
More concretely, scientists have analyzed explorations using magnetic resonance imaging (MRI) or magnetic resonance imaging in the brains of thousands of people around the world.
They found that brain areas associated with learning and development exhibited high levels of variability, meaning that these brain regions more frequently altered their neuronal connections with other parts of the brain in minutes or seconds.
On the other hand, they also found that brain regions not related to intelligence – visual, auditory, or motor areas – showed little variability and adaptability.
*** Potential Applications
This discovery of dynamic functions in the brain could be applied to the construction of advanced artificial neural networks for computers, which could thus acquire the capacity to learn, develop and adapt.
In addition, a more accurate understanding of human intelligence could lead to future developments in artificial intelligence (AI). At present, AI systems do not address the variability and adaptability that are essential for brain development and learning.
This study may also have implications for a deeper understanding of new treatments for mental health disorders.
In this regard, the team observed an alteration of patterns of variability in the so-called default neural network of the brain in patients with disorders such as hyperactivity, schizophrenia, autism, and stroke disorder of warning.
Knowing the brain cause of these mental health problems could improve their treatment and prevention in the future.
*** Default Neural Network (DNN)
It is a set of brain regions that collaborate with each other and could be responsible for much of the activity that develops while the mind is at rest.
DNN shows that the brain is not at rest when it does not intervene in conscious activities (for example, when under the influence of anesthetic). Probably, it emits synchronization signals to coordinate activity between these regions, which would ensure that they are ready to react in a concerted manner to the stimuli. This is a fundamental characteristic of brain function.
*** A Connectome Is a Map of Connections Between Neurons in the Brain.
It is possible for the DNN to establish how the brain organizes memories and various systems that require some preparation for future events. For the rest, if the DNN prepares the brain for a conscious activity, research on its behavior can reveal the keys allowing one to understand the nature of the conscious experience. Similarly, DNN alterations could be the underlying cause of mental errors, the simplest and most complex, ranging from Alzheimer’s disease to depression. To know, how do brains work, is essential even from this point of view.
II – Neuronal Flexibility Is the Secret of How Do Brains Work Better
Researchers at the University of Illinois, in a study published in the journal Trend in Cognitive Sciences in November 2017, suggest that the flexibility of neural wiring could be the key to human intelligence.
Flexibility here refers to the dynamic properties of the brain, that is, how neural connections are structured and how they are modified as a function of environmental conditions. In other words: the adaptability factor.
The authors of the study assert that the evidence collected suggests a neural scaffold effect directly related to an individual’s general intelligence, that is, intelligence does not come from a single region or of a single brain network but is a product of the flexible transition capacity between states of a network.
Scientists have long understood that the brain is modular, which means that different regions of the brain are responsible for specific skills, such as visual information processing by the occipital lobe.
Neuronal Interactions Determines Intelligence
For a long time, we have been trying to understand how the brain is organized and what are the structures responsible for the execution of each function. It is known, for example, that the pre-frontal cortex is responsible for higher-order functions, such as planning and behavioral organization, which scientists have suggested is also the driver of general intelligence. However, the team’s findings indicate that it is in fact a global relationship and that it is the flexibility of neuronal interactions that determines intelligence.
Instead of creating permanent connections, we constantly update our previous knowledge, which involves the formation of new connections. General intelligence requires both the ability to reach close and easily accessible states, to support crystallized intelligence, as well as the ability to adapt and reach states of difficult access to support fluid intelligence.
III – Human Intelligence Depends on Brain Connections
According to a study by scientists from Goethe University in Germany, published in Scientific Reports in November 2017, smart people have regions of the brain that interact more closely with each other, while other regions are disconnected more than others.
When these connections are more intense, the brain quickly selects important information and processes it quickly, eliminating irrelevant information. This selection makes a difference in the expression of a person’s intelligence.
Until now, the degree of intelligence of a person was only attributed to the differences observed in different parts of the brain. But this is not a complete aspect of how do brains work.
Differences in Connection Determine Intelligence
How do brains work in more intelligent people? Researchers believe that an intelligent person’s brain is connected differently from the brain of less intelligent people.
They reached this conclusion after studying the neurological basis of human intelligence. To do this, they combined brain imaging tests of 300 people with magnetic resonance, with other methods of analysis.
These new analyzes show, among other things, that certain areas of the brain of intelligent people participate more intensely in the flow of information between different networks of the brain so that important information is communicated more quickly and efficiently.
The team also discovered that some areas of the brain are less connected to the rest of neural networks in less intelligent people. This means that the smartest people better filter irrelevant information, which affects their ability to respond to other information.
It is possible that the different integration of these regions into brain networks allows smarter people to more easily distinguish important information from irrelevant information, which is a cognitive advantage for many thought processes.
Scientists explain that the functional brain is organized into modules. It’s like a social network formed in turn by several sub-networks, such as families or circles of friends. In each sub-module, members of each family are more closely related to each other than members of other families or circles of friends. The brain works the same way.
What this study has shown is that, in the most intelligent individuals, some of these sub-modules of the brain are more connected and that the exchange of information can quickly separate the important one. In less intelligent people, this exchange of information is less intense, so that the accumulation of information delays the understanding and the decisions that are made more wisely and quickly by the most intelligent people.
An Open Question for Scientists
The causes of these associations remain an open question for scientists. It is possible that some people develop brain networks that promote intelligent behaviors or cognitive tasks that are more difficult because of their biological predispositions. However, it is also likely that the frequent use of the brain for stimulating cognitive tasks may positively affect the development of brain networks. Given the current lack of knowledge about intelligence, an interaction of the two processes seems more likely.
IV – Larger Brain Cells Can Mean More Intelligence
Researchers at the Free University of Amsterdam, in a study published in the scientific journal BioRxiv in May 2018, found evidence suggesting that smarter people have larger neurons.
Human intelligence is an extremely complex feature. To date, many studies have identified areas of the brain that are involved in certain capabilities, or it has been found that certain genes play a role in determining IQ. Other features, such as brain plasticity, are related to the ability to learn and adapt. But little is known about the physical manifestation of this characteristic in neurons.
It is generally accepted that human intelligence depends on the efficiency with which neurons process information that enters the brain and, although it is assumed that human intelligence is related to the thickness of the gray matter of the brain. temporal and frontal lobes, there was no scientific evidence linking the physical and structural properties of neurons and intelligence.
Research on 35 Patients
In order to find those links that have not yet been documented, scientists have studied 35 people who require surgery for a brain tumor or severe epilepsy.
Just before the operation, each person has passed an IQ test. Then, while still in the operating room, the surgeons extracted small samples of healthy brain tissue from the temporal lobes of the patients.
This part of the brain is the one that traditionally associates with intelligence, since that is where what we see is processed, language is recognized and memories are formed.
The team of researchers kept these brain samples alive for analysis. After undergoing various tests, the researchers found that brain cells were significantly larger in people with high IQ than those with a lower score.
Larger Cells Have More “Space” for Memories
Larger cells also have more dendrites – projections that connect to other neurons – and dendrites are longer, suggesting that these neurons might receive and process more information.
Larger neurons have more space for memories. Scientists believe that connections between neurons are involved in storing memories. It is therefore likely that larger cells have more “space” for memories.
The team also tested the ability of neurons to transmit electrical signals by passing a current through them, thus gradually increasing the frequency. The neurons of people with weak IQs coped with low frequencies, but became fatigued and slowed down as the frequency increased. However, the cells of people with high IQ have not decreased.
It is still unclear why some people have larger brain cells than others, whether it is a cause or a consequence of high IQ. It is not known if the differences result from the experiment or if they are determined biologically.
To establish a clear link between the properties of brain cells and intelligence, it will be necessary to study thousands of tissue samples, not just those of 35 people.