Super Brain (21 page)

DIAGRAM 4: THE FUNCTIONAL AREAS
OF THE CEREBRAL CORTEX

The bulk of the brain is the cerebral cortex or cerebrum. Designated the higher brain, it is responsible for many functions we associate with being human: receiving and processing sensory information, learning, memory, and the initiation of thought and action, as well as behavior and social integration.

The cerebral cortex is the most recently evolved part of the brain, consisting of a roughly three-square-foot sheet of neural tissue spread out in six layers toward the outer surface of the brain. (
Cortex
means “bark” or “rind” in Latin.) This sheet of tissue is folded upon itself many times over so that it can fit into the skull. The cerebrum is home to the largest concentration of neurons in the entire brain, roughly 40 billion.

The cerebral cortex has three main functional areas: the sensory regions for receiving and processing the five senses, the motor regions for controlling voluntary movement, and the association regions for intellect, perception, learning, memory, and higher order thinking.

DIAGRAM 5: THE REGIONS OF THE
CEREBRAL CORTEX

The cerebral cortex is made up of a number of different lobes. Toward the back of the cerebral cortex is the occipital lobe, containing the visual cortex, where the brain relays and interprets information being perceived by your eyes. The left visual cortex connects with the right eye and vice versa. Toward the front of the occipital lobes are the temporal lobes. Here lie the primitive instinct-driven emotions that serve survival: fear, desire, and appetites such as hunger and sexuality. Hearing and balance are also controlled here. When this area of the brain is damaged or malfunctioning, a person may suffer uncontrollable appetites for food and sex.

In front of and above the temporal lobes are the parietal lobes, where sensory information is processed along with spatial orientation, which lets you know where you are. Finally, in front of the parietal lobes are the frontal lobes. The frontal lobes regulate motor control and movement but also mediate our behavior in society. If the frontal cortex is damaged or, for example, contains a tumor, one might become pathologically uninhibited and turn into an extreme exhibitionist or even a sexual molester.

The right and left hemispheres of the cerebral cortex are connected by bundles of nerve fibers called the corpus callosum. They allow the two sides of the brain to “talk” to each other. If they did not, one might experience “alien hand syndrome,” in which one does not recognize one’s own hand! Tucked under the corpus callosum is the limbic system (see Diagram 5), which contains the thalamus and hypothalamus. The thalamus is involved in sensory perception and regulates movement. The hypothalamus regulates hormones, the pituitary gland, body temperature, the adrenal glands, and many other activities.

The two other major sections of the brain are the cerebellum, toward the rear of the brain, which controls coordination of movement, balance, and posture; and the brain stem (medulla oblongata and pons), which is the oldest part of the brain. It connects the brain to the spinal cord and regulates heart rate, breathing, and other so-called autonomic processes that take place automatically.

The functions of the brain that control physiological processes—from heart rate to fear response to the immune system—are concentrated in specific regions of the cerebral cortex, cerebellum, or brain stem. But these regions also communicate with one another to create an intricate system of balance and coordination as part of every brain activity. For example, when you look at a flower, your eyes sense that visual information and relay it to the occipital cortex, a region of the cerebral cortex toward the back of the brain. But first that same visual information travels through multiple other areas of the brain, where it may also serve to coordinate your movements in response to the visual information. The billions of neurons in these regions work together in exquisite balance and harmony, similar to the way an orchestra makes beautiful music. There is no room for one instrument to be too loud or off key. Balance and harmony are the keys to a successful brain, just as they are for the stability of the universe.

But intuition has also been a suspect area. A curious irony of the brain is that the intellectual brain can dismiss the intuitive brain as mere superstition, bordering on belief in the paranormal. Rupert Sheldrake, a far-seeing British biologist, has done decades of experiments to verify intuition. For example, he has tested the common experience of feeling that you are being watched, usually by someone standing behind you. Do we have eyes in the back of our head? If so, this would be an intuitive ability, and Sheldrake has shown that it exists. For his pains, his work is considered controversial, which means, as Sheldrake wryly notes, that skeptics haven’t actually bothered to look at his results.

But the fact that humans are intuitive is uncontroversial. Whole areas of your life depend upon intuition—empathy, for example. When you walk into a room, you can sense if the people in it are tense or have been fighting before you arrived—that’s intuitive. You intuit when someone is saying A but means B, or when someone who is holier than thou is hiding a secret.

Empathy is defined as the understanding and sharing of others’ feelings. In
Homo sapiens
, as the ability to communicate took a quantum leap forward, empathy became a critical component for social survival. It allowed parents to care for the group’s children while some adults were absent to hunt and gather. Empathy still enables us to live in groups and socialize with each other, serving as the necessary curb to selfish aggression and competition (a balance that society struggles to maintain).

More broadly, empathy has paved the way for moral reasoning and altruistic behavior. (The Latin roots of
compassion
mean “to suffer with,” pointing to our ability to mirror what we see another person feeling.) Empathy is different from sympathy, which does not involve sharing another’s state of mind. It is also different from
emotional contagion
, in which one is not aware of whether the emotion belongs to oneself or has been absorbed by contact with a stronger personality, or the crowd.

At the neural level, the main area of the brain activated by empathy is the cingulate cortex.
Cingulum
means “belt” in Latin. The cingulate lies like a belt in the middle of the cerebral cortex and is considered part of the limbic system, which deals with emotion, learning, and memory. This is where empathy physically resides. The empathy-associated regions of the cingulate gyrus are larger in females than in males and are generally smaller in schizophrenic patients, who are often tragically isolated in their emotions and delusional about what other people are feeling.

Empathy has also been associated with
mirror neurons
, a class of nerve cells that are known to exist in lower primates like monkeys. There is a neuronal reason for “monkey see, monkey do” that is critical to learning new skills. When a baby monkey, even one still young enough to breast-feed, sees its mother grasp food and eat it, the areas in its brain responsible for grasping, tearing food apart, and chewing light up—they mirror what it sees. Experiments cannot be performed on human infants to determine if the same is
occurring in our species, but in all likelihood it is. (The pernicious side of mirroring may be that when a young child witnesses negative behavior, such as domestic abuse, a brain pattern may be triggered. It is known that abused children often grow up to become abusers, so imprinted are they with such behavior.)

No one knows the full functioning of mirror neurons, but they seem to play a key role in social attachment, the process by which we attain security, nurturing, and alleviation of distress from our relationships. A host of neurochemicals called neuropeptides—small proteins in the brain that regulate social attachment, including oxytocin, opioids, and prolactin—regulate empathic responsiveness.

Oxytocin facilitates maternal behavior and makes one feel “in love.” The application of oxytocin via nasal spray has been shown to reduce responses to social stress and the fear responses in the brain. Oxytocin can also increase mutual trust and make one more sensitive to others’ facial expressions. An adverse gene mutation in the receptor that binds oxytocin causes one to have lower levels of empathy. Thus oxytocin plays a critical role, and yet its popular name, “the love hormone,” should not be taken literally. Love, being a complex behavior, is sensitive to many responses throughout the brain, and a single hormone cannot be held as its cause. We are confronted with the riddle of where mind ends and brain begins. Anyone who has ever fallen madly in love will testify that this mystery gets very personal. Humans have evolved a biological structure in the brain that grew from the mating of lower mammals, but we make all kinds of choices about how we love and who attracts us. Biology may provide the juice, but it doesn’t take over from the mind.

All such issues lead back to free will, which we believe is always dominant in human life. But we can interpret the fact that neurochemicals can control our emotions, including love and empathy, in two ways. On one hand, we can say we have no control over how we feel; we are slaves to our neurochemistry with little or no free will. Alternatively, from the super brain point of view, we can argue
that the brain is an incredibly fine-tuned organ that produces the emotions we need at any given moment. The brain needs triggers, which can be very subtle. Meeting an attractive man is different for a woman depending on whether she is “in the market.” If she is not, her brain’s love mechanism isn’t triggered; if she is, the opposite is true. In either event, the brain did not make the woman’s decision for her. Despite their undeniable power, our emotions are generated to serve us.

This is where intuitive mind enters the picture. It rises above emotion and intellect, giving you an overall picture of things (which psychologists call a
gestalt
, the image of reality we assign to various situations). At work, the person in charge doesn’t have to wear a sign that says, “I’m the boss.” All kinds of signals (such as his tone of voice, his big office, his air of authority) merge into a picture that we intuitively grasp. We say that we “feel out” a situation, but this isn’t the same as an emotion. It’s the feeling that tells you what is going on all at once, instead of having to assemble a picture one emotional or intellectual piece at a time.

All of the following things fall under the category of intuition:

Falling in love at first sight.

Knowing that someone else is lying.

Feeling that things happen for a reason, even if the reason hasn’t yet emerged.

Using irony, which says one thing but means the opposite.

Laughing at a joke.

Intuition would be less controversial if it were isolated in a specific location in the brain, but it isn’t. The most popular belief is that the right hemisphere of the brain is responsible for intuition while the left is rational and objective, but this neat division hasn’t held up to rigorous testing. Still, the hallmarks of intuitive people are well confirmed:

They make quick decisions without going through a rational process, yet their decisions are just as accurate.

They pick up on subtle facial expressions.

They rely on insight, defined as knowing something directly without waiting for reason to arrive at a conclusion.

They make creative leaps.

They are good judges of character—they know how to read people.

They trust and follow their first instinct, in so-called “blink” or snap judgments.

For anyone who trusts their intuition, this last category of snap judgments is especially intriguing. Traditionally, we value other kinds of judgments more. Young people are advised not to be rash, to think things through, and to arrive at a considered judgment. But in reality we all make snap decisions. Hence the saying that you can’t take back a first impression. First impressions, made in the blink of an eye, are the most powerful. What has emerged from recent studies is that first impressions and snap judgments are often the most accurate. Experienced real estate brokers will tell you that home buyers know within thirty seconds of walking into a house whether it is right for them or not.

It was long assumed that a person can recognize faces better if he first goes through the process of verbally describing the face.
The girl had long brown hair, fair skin, a button nose, and small blue eyes
is supposed to help fix a certain face in your memory. But experiments show the opposite. One study flashed a series of photos in fast succession, asking subjects to press a button if they saw a particular face flash by. People who had glimpsed the face only briefly did better at this than people who saw the face and were given time to verbalize its features. Such findings seem intuitively right (there’s that word again), because we all know what it means to have someone’s face
stick in the mind even though we don’t rationally break it down into separate features. We also believe victims of a crime who say, “I’d know that face in a million years if I ever saw it again.”