Synopsis
Book by Braverman Eric R
Extrait
Chapter 1
Brain Basics: What's Going On Inside Your Head
The brain is the most remarkable organ in the body: It not only controls how you think, feel, and perceive, it manages all aspects of your health. It is responsible for how your body moves, digests, and ages. Most important, it generates the energy you need to fulfill these functions through the creation and dispersion of electricity.
Some say that the brain is like a supercomputer, but I imagine it more like the circuit box in your home. Whenever you want to turn on a light, you plug a lamp into an outlet, and electricity is transferred across the wires inside the walls directly from the circuit box to the lamp. The brain sends electric currents throughout your body in much the same way.
The brain's electrical activity typically begins with a stimulus: a thought, or a reaction from any of the five senses. When your brain receives the information from your sensory nerves, it, like the circuit box, sends electric messages down to the body in response. All the signals going to and from your brain travel through your internal wires, which are housed in your spinal cord. Together, the brain and spinal cord are called the central nervous system.
The smallest components of the central nervous system are billions of special cells called neurons. We are born with 100 billion neurons, and we now know that we can continue to produce them throughout our lives (this is where neurogenesis comes in). Every neuron has a gender as well as a nucleus (or head), arms called dendrites, and legs (or axons).
Each neuron has 10,000 axons and dendrites, which connect to other neurons to create your body's electrical network. Neurons come extremely close to one another but do not completely touch. The in-between space is called a synaptic gap. Each of us has 100 trillion of these neuron-to-neuron synapses. In this space, the axon of a neuron connects with the dendrite of another neuron. This connection activates the circuitry of the brain, literally flipping on a switch, which creates electricity and allows the electricity to pass continuously through them.
There are four measurements that determine the relationship between brain function and the creation and delivery of electricity. These are critical to maintain in order to build the most efficient and effective brain.
Voltage. Voltage measures your brain's power and output: the intensity at which it responds to any sensory stimulus--taste, touch, smell, sound, sight--and the brain's ability to process this information. Voltage determines your body's metabolism, or how fast it can convert food into fuel. It also measures the various states of consciousness, ranging from full alertness to deep sleep. Without proper voltage, you literally slow down--and so does your thinking.
The smartest brains rely on high levels of voltage. These people are quick thinkers with lots of cognitive energy and a healthy sense of curiosity, and they live with a sense of urgency. They pay attention to the details of life and can focus all their attention on completing a task, because there is always another accomplishment waiting for them to tackle.
Speed. The speed of your brain determines how quickly the electrical signals are processed. It is a measure of the intensity of how the brain is working. For example, the brain's electricity typically runs through the body at 60 cycles per second. Thinking occurs even faster, at only 2 to 3 cycles per second. The ability to maintain this rate determines your brain's "age," which might be very different from your actual age. As you can imagine, a younger brain is a faster brain. By increasing your brain speed, you can improve memory, IQ, and even behavior.
Balance. A balanced brain creates and receives electricity in a smooth, rhythmic flow. When the brain's electricity is generated and delivered evenly, you can achieve physical and emotional balance. You are in sync with others, have an overall sense of calmness, and possess a solid ability to handle stressful situations. However, when this same electricity is delivered in uneven bursts, you might feel anxious, irritable, or in pain. A balanced brain is the key to maintaining a happy, positive outlook on life, which allows you to become more empathetic and intuitive as you get smarter.
Synchrony. The brain's electricity moves as waves. There are four types of brain waves, each providing us with a level of physical as well as mental consciousness. The first type is beta, which travels at a rate of 12 to 16 cycles per second. When your brain is transmitting beta waves, you feel alert. The second type is alpha, and these waves travel at a rate of 8 to 12 cycles per second. When your brain is transmitting alpha waves, you feel creative. Theta waves travel at a rate of 4 to 8 cycles per second. When your brain is transmitting theta waves, you can feel drowsy. Last are delta waves, which travel at a rate of 1 to 4 cycles per second. When your brain is transmitting delta waves, you sleep.
These four brain waves always appear in some combination. You might feel alert and creative, or experience a deep sleep with extremely vivid dreams. True synchrony occurs when all four brain waves are coordinated throughout the day and night. When these brain waves get out of sync at night, you will not experience restful sleep; during the day, you'll find that your mind is wandering and your concentration is affected.
THE ELECTROCHEMICAL BRAIN
Each cell on the neuronal highway is programmed to produce, send, and receive a specific chemical, whose job is to activate brain cells to fire messages at each other by moving to various receptor sites within the brain's synapses. These receptors are like fingers on a glove: each one fitting only one part of your hand. When the receptors capture specific chemicals, your brain alters how your mind and body functions. The brain's chemistry generates the electricity, which then supplies power to the rest of the body.
Each chemical travels along a different path, resulting in a variety of physical processes as well as maintaining a high-powered, fast-moving, stable, and well-rested brain. The density of these chemicals is the key to your well-being: If there is an excess, the synapses are flooded and the signals can't get to the next neuron; if there is a deficiency, the nerve signals have nothing to travel on. Different parts of the body will react to brain chemical excesses and deficiencies by overworking or shutting down, leading to physical illness and cognitive decline.
There are four major brain chemical systems that travel on the neuronal highway: the catecholamine system, the cholinergic system, the GABAergic system, and the serotonergic system. Each of these is also related to the way electricity is distributed.
The key to boosting brain health is to balance the four categories of brain chemistry while you create new healthy brain cells.
. The catecholamine system features the brain chemical dopamine, which determines voltage. It is directly related to adrenaline, and the feeling you experience when you are excited. Dopamine controls bodily functions related to power, including blood pressure, metabolism, and digestion. Dopamine generates the electricity that controls voluntary movement, intelligence, abstract thought, goal setting, and long-term planning. A loss of dopamine results in decreased brain power, leading to fatigue, addiction, and a loss of attention. . The cholinergic system features the chemical acetylcholine, which determines your brain's processing speed. This brain chemical family also acts as a lubricant and is necessary to keep the internal structures of the body moist so that energy and information can easily pass through each system. When your acetylcholine levels are high, you are creative and feel good about yourself. A loss of acetylcholine significantly decreases brain speed, resulting in "brain fog," which is what you experience when your thinking becomes disjointed. In extreme cases, it is linked to dementia and Alzheimer's disease, a type of dementia that occurs when the brain "forgets" how to take care of the body. . The GABAergic system features gamma-aminobutyric acid, or GABA. This brain chemical is connected to electrical balance. It affects your stability and calmness. I like to think of GABA as the brain's natural Valium. When your GABA levels are correct, your mood is even and you can make good decisions. GABA is also involved in the production of endorphins, those "feel-good" hormones that are produced in the brain during a physical release, such as stretching, exercise, or even sex. A chemical imbalance of GABA causes headaches, palpitations, seizures, and anxiety. . The serotonergic system features the brain chemical serotonin. Serotonin is connected to synchrony. It provides a healing, nourishing, satisfied feeling to the brain and body. Serotonin stimulates the growth of new neuronal connections, while the other brain chemical families ensure synaptic activity in existing neurons. When your serotonin levels are optimal, you can sleep deeply and think rationally. When they are out of balance, the effects include depression, sleep disorders, eating disorders, and sensory processing dysfunction.
Even when we are young, very few people are extremely high in only one brain chemical, or only low in another. Most of us are a combination of highs and lows. In fact, brain chemicals are synergistically related to each other. For example, dopamine and serotonin often work in conjunction with each other: When one is high, the other is low. Dopamine and acetylcholine are the brain's "on" switches, providing you with lots of energy. GABA and serotonin are the "off" switches--they help calm the body.
When your brain is balanced, you are creating the exact right amount of each of these chemicals, and you will feel energetic, creative, and calm, and will have the ability to reset your brain with restful sleep at night. But as get older, the structure of the neuronal highway gets worn down and becomes less efficient as both a chemical producer and transmitter. That's when you start to lose the speed of acetylcholine or the energy of dopamine. Without these, you will feel the low-serotonin blues, which lead to higher anxiety as GABA becomes imbalanced, which forces a low-serotonin inability to sleep. Dementia occurs when all the brain chemicals fail.
All these symptoms can contribute to your feeling older than your actual age, because they are literally aging your brain. And when that happens, you start to feel like you are losing your mind. This is why a youthful brain is perhaps the most crucial challenge of aging, and why you must keep your brain as young as possible throughout your life.
THE ANATOMY OF THE ELECTRIC BRAIN
The neurons that produce and receive the specific brain chemical families are located in particular regions of the brain. The brain is divided into three parts: the cerebrum, the brain stem, and the cerebellum. The cerebrum is further divided into two hemispheres that are linked by a thick band of nerve fibers called the corpus callosum. These hemispheres have identical areas that are designated as lobes. Each hemisphere of the cerebrum is divided into four lobes, and the cerebellum houses three. All of these lobes, in conjunction with the brain stem, control the automatic processes, such as breathing and digesting, and formulate our total health by managing all our other internal systems. Each lobe also directs mental functions: how we think, reason, create, and remember.
The Cerebrum
The cerebrum is what most of us think of when we picture the brain. It is covered by the cerebral cortex, which is the outer surface of folded bulges that increase its surface area and, therefore, increases the amount of information that the brain can process.
The cerebral cortex and the cerebrum together play a key role in memory, attention, perceptual awareness, thought, language, and consciousness. The largest part of the brain, the cerebrum, comprises both the left and right hemispheres of the brain, each of which contains four pairs of lobes. These lobes receive electrical currents from the central nervous system and translate them into specific chemical signals. Each pair is dominated by one of the four primary brain chemical families and associated with its corresponding measurement of electricity. A chemical surplus or deficiency within these lobes is what ultimately controls your thinking, your personality, and your health.
Frontal lobes. Every part of your body is connected to nerve cells that eventually lead to the frontal lobes. Through these connections the body receives the sensory signals associated with touch, including feelings of heat and coldness. The frontal lobes control your brain's voltage, or power. Beta brain waves are created in the frontal lobes from the neurons that produce dopamine and the other catecholamines. These lobes contain two parts, both of which are affected by levels of dopamine: The anterior (front) portion of the frontal lobe is called the prefrontal cortex. It is very important for developing and maintaining your cognitive functions and your ability to focus, as well as your personality. The posterior (back) of the frontal lobe consists of the premotor and motor areas. Nerve cells that produce movement are located in these motor areas.
Parietal lobes. Parietal lobes are the thinking factory of your brain. Seated just behind the frontal lobes, the parietal lobes control brain processing speed and help the brain recognize and react to sensory signals involved with sound, smell, taste, and visuospatial processing. The neurons here produce acetylcholine and its associated alpha waves.
Temporal lobes. Located just above the ears, the temporal lobes house the brain's ability to store memory and language. The neurons in these lobes produce the chemical GABA in the form of theta brain waves. These lobes assist in balancing the frontal lobes with the parietal lobes, orchestrating the connection between personality, movement, thinking, and action. While the frontal and parietal lobes are the leaders of the brain, the temporal lobes are the wings of creativity, stabilizing the brain.
Occipital lobes. These lobes, found at the rear of the brain, control vision. They also control your brain's ability to rest and resynchronize by producing the chemical serotonin and its resulting delta waves.
The Brain Conducts Energy from the Outside
We walk by hundreds of people every day who aren't looking directly at us. But we always seem to notice when someone is looking directly at us. That connection occurs because the brain is both an energy provider and an energy conductor. When someone is staring at you, your brain will pick up on their electric energy, and you will involuntarily turn your head toward them.
The Corpus Callosum
The corpus callosum is like the Internet of the brain: It's the place where every brain cell has to connect so that the brain can work as a whole. This band of neuronal fibers is the electrical network between the right and left hemispheres, allowing the two sides of the brain to coordinate their tasks.
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