How to Create a Mind: The Secret of Human Thought Revealed

Our emotional thoughts also take place in the neocortex but are influenced by portions of the brain ranging from ancient brain regions such as the amygdala to some evolutionarily recent brain structures such as the spindle neurons, which appear to play a key role in higher-level emotions. Unlike the regular and logical recursive structures found in the cerebral cortex, the spindle neurons have highly irregular shapes and connections. They are the largest neurons in the human brain, spanning its entire breadth. They are deeply interconnected, with hundreds of thousands of connections tying together diverse portions of the neocortex.

As mentioned earlier, the insula helps process sensory signals, but it also plays a key role in higher-level emotions. It is this region from which the spindle cells originate. Functional magnetic resonance imaging (fMRI) scans have revealed that these cells are particularly active when a person is dealing with emotions such as love, anger, sadness, and sexual desire. Situations that strongly activate them include when a subject looks at her partner or hears her child crying.

Spindle cells have long neural filaments called apical dendrites, which are able to connect to faraway neocortical regions. Such “deep” interconnectedness, in which certain neurons provide connections across numerous regions, is a feature that occurs increasingly as we go up the evolutionary ladder. It is not surprising that the spindle cells, involved as they are in handling emotion and moral judgment, would have this form of connectedness, given the ability of higher-level emotional reactions to touch on diverse topics and thoughts. Because of their links to many other parts of the brain, the high-level emotions that spindle cells process are affected by all of our perceptual and cognitive regions. It is important to point out that these cells are not doing rational problem solving, which is why we don’t have rational control over our responses to music or over falling in love. The rest of the brain is heavily engaged, however, in trying to make sense of our mysterious high-level emotions.

There are relatively few spindle cells: only about 80,000, with approximately 45,000 in the right hemisphere and 35,000 in the left. This disparity is at least one reason for the perception that emotional intelligence is the province of the right brain, although the disproportion is modest. Gorillas have about 16,000 of these cells, bonobos about 2,100, and chimpanzees about 1,800. Other mammals lack them completely.

Anthropologists believe that spindle cells made their first appearance 10 to 15 million years ago in the as yet undiscovered common ancestor to apes and hominids (precursors to humans) and rapidly increased in numbers around 100,000 years ago. Interestingly, spindle cells do not exist in newborn humans but begin to appear only at around the age of four months and increase significantly in number from ages one to three. Children’s ability to deal with moral issues and perceive such higher-level emotions as love develop during this same period.

Aptitude

Wolfgang Amadeus Mozart (1756–1791) wrote a minuet when he was five. At age six he performed for the empress Maria Theresa at the imperial court in Vienna. He went on to compose six hundred pieces, including forty-one symphonies, before his death at age thirty-five, and is widely regarded as the greatest composer in the European classical tradition. One might say that he had an aptitude for music.

So what does this mean in the context of the pattern recognition theory of mind? Clearly part of what we regard as aptitude is the product of nurture, that is to say, the influences of environment and other people. Mozart was born into a musical family. His father, Leopold, was a composer and kapellmeister (literally musical leader) of the court orchestra of the archbishop of Salzburg. The young Mozart was immersed in music, and his father started teaching him the violin and clavier (a keyboard instrument) at the age of three.

However, environmental influences alone do not fully explain Mozart’s genius. There is clearly a nature component as well. What form does this take? As I wrote in chapter 4, different regions of the neocortex have become optimized (by biological evolution) for certain types of patterns. Even though the basic pattern recognition algorithm of the modules is uniform across the neocortex, since certain types of patterns tend to flow through particular regions (faces through the fusiform gyrus, for example), those regions will become better at processing the associated patterns. However, there are numerous parameters that govern how the algorithm is actually carried out in each module. For example, how close a match is required for a pattern to be recognized? How is that threshold modified if a higher-level module sends a signal that its pattern is “expected”? How are the size parameters considered? These and other factors have been set differently in different regions to be advantageous for particular types of patterns. In our work with similar methods in artificial intelligence, we have noticed the same phenomenon and have used simulations of evolution to optimize these parameters.

If particular regions can be optimized for different types of patterns, then it follows that individual brains will also vary in their ability to learn, recognize, and create certain types of patterns. For example, a brain can have an innate aptitude for music by being better able to recognize rhythmic patterns, or to better understand the geometric arrangements of harmonies. The phenomenon of perfect pitch (the ability to recognize and to reproduce a pitch without an external reference), which is correlated with musical talent, appears to have a genetic basis, although the ability needs to be developed, so it is likely to be a combination of nature and nurture. The genetic basis of perfect pitch is likely to reside outside the neocortex in the preprocessing of auditory information, whereas the learned aspect resides in the neocortex.

There are other skills that contribute to degrees of competency, whether of the routine variety or of the legendary genius. Neocortical abilities—for example, the ability of the neocortex to master the signals of fear that the amygdala generates (when presented with disapproval)—play a significant role, as do attributes such as confidence, organizational skills, and the ability to influence others. A very important skill I noted earlier is the courage to pursue ideas that go against the grain of orthodoxy. Invariably, people we regard as geniuses pursued their own mental experiments in ways that were not initially understood or appreciated by their peers. Although Mozart did gain recognition in his lifetime, most of the adulation came later. He died a pauper, buried in a common grave, and only two other musicians showed up at his funeral.

Creativity

A key aspect of creativity is the process of finding great metaphors—symbols that represent something else. The neocortex is a great metaphor machine, which accounts for why we are a uniquely creative species. Every one of the approximately 300 million pattern recognizers in our neocortex is recognizing and defining a pattern and giving it a name, which in the case of the neocortical pattern recognition modules is simply the axon emerging from the pattern recognizer that will fire when that pattern is found. That symbol in turn then becomes part of another pattern. Each one of these patterns is essentially a metaphor. The recognizers can fire up to 100 times a second, so we have the potential of recognizing up to 30 billion metaphors a second. Of course not every module is firing in every cycle—but it is fair to say that we are indeed recognizing millions of metaphors a second.

Of course, some metaphors are more significant than others. Darwin perceived that Charles Lyell’s insight on how very gradual changes from a trickle of water could carve out great canyons was a powerful metaphor for how a trickle of small evolutionary changes over thousands of generations could carve out great changes in the differentiation of species. Thought experiments, such as the one that Einstein used to illuminate the true meaning of the Michelson-Morley experiment, are all metaphors, in the sense of being a “thing regarded as representative or symbolic of something else,” to quote a dictionary definition.

Do you see any metaphors in Sonnet 73 by Shakespeare?

In this sonnet, the poet uses extensive metaphors to describe his advancing age. His age is like late autumn, “when yellow leaves, or none, or few, do hang.” The weather is cold and the birds can no longer sit on the branches, which he calls “bare ruin’d choirs.” His age is like the twilight as the “sunset fadeth in the west, which by and by black night doth take away.” He is the remains of a fire “that on the ashes of his youth doth lie.” Indeed, all language is ultimately metaphor, though some expressions of it are more memorable than others.

Finding a metaphor is the process of recognizing a pattern despite differences in detail and context—an activity we undertake trivially every moment of our lives. The metaphorical leaps that we consider of significance tend to take place in the interstices of different disciplines. Working against this essential force of creativity, however, is the pervasive trend toward ever greater specialization in the sciences (and just about every other field as well). As American mathematician Norbert Wiener (1894–1964) wrote in his seminal book Cybernetics, published the year I was born (1948):

There are fields of scientific work, as we shall see in the body of this book, which have been explored from the different sides of pure mathematics, statistics, electrical engineering, and neurophysiology; in which every single notion receives a separate name from each group, and in which important work has been triplicated or quadruplicated, while still other important work is delayed by the unavailability in one field of results that may have already become classical in the next field.

It is these boundary regions which offer the richest opportunities to the qualified investigator. They are at the same time the most refractory to the accepted techniques of mass attack and the division of labor.

A technique I have used in my own work to combat increasing specialization is to assemble the experts that I have gathered for a project (for example, my speech recognition work included speech scientists, linguists, psychoacousticians, and pattern recognition experts, not to mention computer scientists) and encourage each one to teach the group his particular techniques and terminology. We then throw out all of that terminology and make up our own. Invariably we find metaphors from one field that solve problems in another.

A mouse that finds an escape route when confronted with the household cat—and can do so even if the situation is somewhat different from what it has ever encountered before—is being creative. Our own creativity is orders of magnitude greater than that of the mouse—and involves far more levels of abstraction—because we have a much larger neocortex, which is capable of greater levels of hierarchy. So one way to achieve greater creativity is by effectively assembling more neocortex.

One approach to expand the available neocortex is through the collaboration of multiple humans. This is accomplished routinely via the communication between people gathered in a problem-solving community. Recently there have been efforts to use online collaboration tools to harness the power of real-time collaboration, which have shown success in mathematics and other fields.¹

The next step, of course, will be to expand the neocortex itself with its nonbiological equivalent. This will be our ultimate act of creativity: to create the capability of being creative. A nonbiological neocortex will ultimately be faster and could rapidly search for the kinds of metaphors that inspired Darwin and Einstein. It could systematically explore all of the overlapping boundaries between our exponentially expanding frontiers of knowledge.

Some people express concern about what will happen to those who would opt out of such mind expansion. I would point out that this additional intelligence will essentially reside in the cloud (the exponentially expanding network of computers that we connect to through online communication), where most of our machine intelligence is now stored. When you use a search engine, recognize speech from your phone, consult a virtual assistant such as Siri, or use your phone to translate a sign into another language, the intelligence is not in the device itself but in the cloud. Our expanded neocortex will be housed there too. Whether we access such expanded intelligence through direct neural connection or the way we do now—by interacting with it via our devices—is an arbitrary distinction. In my view we will all become more creative through this pervasive enhancement, whether we choose to opt in or out of direct connection to humanity’s expanded intelligence. We have already outsourced much of our personal, social, historical, and cultural memory to the cloud, and we will ultimately do the same thing with our hierarchical thinking.

Einstein’s breakthrough resulted not only from his application of metaphors through mind experiments but also from his courage in believing in the power of those metaphors. He was willing to relinquish the traditional explanations that failed to satisfy his experiments, and he was willing to withstand the ridicule of his peers to the bizarre explanations that his metaphors implied. These qualities—belief in metaphor and courage of conviction—are ones that we should be able to program into our nonbiological neocortex as well.

Love

If you haven’t actually experienced ecstatic love personally, you have undoubtedly heard about it. It is fair to say that a substantial fraction if not a majority of the world’s art—stories, novels, music, dance, paintings, television shows, and movies—is inspired by the stories of love in its earliest stages.

Science has recently gotten into the act as well, and we are now able to identify the biochemical changes that occur when someone falls in love. Dopamine is released, producing feelings of happiness and delight. Norepinephrine levels soar, which lead to a racing heart and overall feelings of exhilaration. These chemicals, along with phenylethylamine, produce elation, high energy levels, focused attention, loss of appetite, and a general craving for the object of one’s desire. Interestingly, recent research at University College in London also shows that serotonin levels go down, similar to what happens in obsessive-compulsive disorder, which is consistent with the obsessive nature of early love.² The high levels of dopamine and norepinephrine account for the heightened short-term attention, euphoria, and craving of early love.

If these biochemical phenomena sound similar to those of the fight-or-flight syndrome, they are, except that here we are running toward something or someone; indeed, a cynic might say toward rather than away from danger. The changes are also fully consistent with those of the early phases of addictive behavior. The Roxy Music song “Love Is the Drug” is quite accurate in describing this state (albeit the subject of the song is looking to score his next fix of love). Studies of ecstatic religious experiences also show the same physical phenomena; it can be said that the person having such an experience is falling in love with God or whatever spiritual connection on which they are focused.

In the case of early romantic love, estrogen and testosterone certainly play a role in establishing sex drive, but if sexual reproduction were the only evolutionary objective of love, then the romantic aspect of the process would not be necessary. As psychologist John William Money (1921–2006) wrote, “Lust is lewd, love is lyrical.”

The ecstatic phase of love leads to the attachment phase and ultimately to a long-term bond. There are chemicals that encourage this process as well, including oxytocin and vasopressin. Consider two related species of voles: the prairie vole and the montane vole. They are pretty much identical, except that the prairie vole has receptors for oxytocin and vasopressin, whereas the montane vole does not. The prairie vole is noted for lifetime monogamous relationships, while the montane vole resorts almost exclusively to one-night stands. In the case of voles, the oxytocin and vasopressin receptors are pretty much determinative as to the nature of their love life.

While these chemicals are influential on humans as well, our neocortex has taken a commanding role, as in everything else we do. Voles do have a neocortex, but it is postage-stamp sized and flat and just large enough for them to find a mate for life (or, in the case of montane voles, at least for the night) and carry out other basic vole behaviors. We humans have sufficient additional neocortex to engage in the expansive “lyrical” expressions to which Money refers.

From an evolutionary perspective, love itself exists to meet the needs of the neocortex. If we didn’t have a neocortex, then lust would be quite sufficient to guarantee reproduction. The ecstatic instigation of love leads to attachment and mature love, and results in a lasting bond. This in turn is designed to provide at least the possibility of a stable environment for children while their own neocortices undergo the critical learning needed to become responsible and capable adults. Learning in a rich environment is inherently part of the method of the neocortex. Indeed the same oxytocin and vasopressin hormone mechanisms play a key role in establishing the critical bonding of parent (especially mother) and child.

At the far end of the story of love, a loved one becomes a major part of our neocortex. After decades of being together, a virtual other exists in the neocortex such that we can anticipate every step of what our lover will say and do. Our neocortical patterns are filled with the thoughts and patterns that reflect who they are. When we lose that person, we literally lose part of ourselves. This is not just a metaphor—all of the vast pattern recognizers that are filled with the patterns reflecting the person we love suddenly change their nature. Although they can be considered a precious way to keep that person alive within ourselves, the vast neocortical patterns of a lost loved one turn suddenly from triggers of delight to triggers of mourning.

The evolutionary basis for love and its phases is not the full story in today’s world. We have already largely succeeded in liberating sex from its biological function, in that we can have babies without sex and we can certainly have sex without babies. The vast majority of sex takes place for its sensual and relational purposes. And we routinely fall in love for purposes other than raising children.

Similarly, the vast expanse of artistic expression of all kinds that celebrates love and its myriad forms dating back to antiquity is also an end in itself. Our ability to create these enduring forms of transcendent knowledge—about love or anything else—is precisely what makes our species unique.

The neocortex is biology’s greatest creation. In turn, it is the poems about love—and all of our other creations—that represent the greatest inventions of our neocortex.