The Future of the Mind by Kaku
Ref: Michiel Kaku (2014). The Future of the Mind. Random House.
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Summary
Theoretical Physicist Michiel Kaku delves into the most fascinating and complex object in the known universe: the human brain. For the first time in history, the secrets of the living brain are being revealed by a battery of high tech brain scans devised by physicists. Now what was once solely the province of science fiction has become a startling reality. Recording memories, telepathy, videotaping our dreams, mind control, avatars, and telekinesis are not only possible; they already exist. The Future of the Mind gives us an authoritative and compelling look at the astonishing research being done in top laboratories around the world—all based on the latest advancements in neuroscience and physics. One day we might have a "smart pill" that can enhance our cognition; be able to upload our brain to a computer, neuron for neuron; send thoughts and emotions around the world on a "brain-net"; control computers and robots with our mind; push the very limits of immortality; and perhaps even send our consciousness across the universe. Dr. Kaku takes us on a grand tour of what the future might hold, giving us not only a solid sense of how the brain functions but also how these technologies will change our daily lives. He even presents a radically new way to think about "consciousness" and applies it to provide fresh insight into mental illness, artificial intelligence and alien consciousness (Goodreads).
SPACE-TIME THEORY OF CONSCIOUSNESS: Animals, plants, and even machines can be conscious. Consciousness, I claim, is the process of creating a model of yourself using multiple feedback loops—for example, in space, in society, or in time—in order to carry out a goal. To measure consciousness, we simply count the number and types of feedback loops necessary for subjects to achieve a model of themselves. The smallest unit of consciousness might be found in a thermostat or photocell, which employs a single feedback loop to create a model of itself in terms of temperature or light. A flower might have, say, ten units of consciousness, since it has ten feedback loops measuring water, temperature, the direction of gravity, sunlight, et cetera. In my theory, these loops can be grouped according to a certain level of consciousness.
Level 0: Thermostats and flowers would belong to Level 0.
Level 1: includes that of reptiles, fruit flies, and mosquitos, which generate models of themselves with regard to space. A reptile has numerous feedback loops to determine the coordinates of its prey and the location of potential mates, potential rivals, and itself.
Level 2: involves social animals. Their feedback loops relate to their pack or tribe and produce models of the complex social hierarchy within the group as expressed by emotions and gestures. These levels roughly mimic the stages of evolution of the mammalian brain. The most ancient part of our brain is at the very back, where balance, territoriality, and instincts are processed. The brain expanded in the forward direction and developed the limbic system, the monkey brain of emotions, located in the center of the brain. This progression from the back to the front is also the way a child’s brain matures.
So, then, what is human consciousness in this scheme? What distinguishes us from plants and animals? I theorize that humans are different from animals because we understand time. We have temporal consciousness in addition to spatial and social consciousness. The latest part of the brain to evolve is the prefrontal cortex, which lies just behind our forehead. It is constantly running simulations of the future. Animals may seem like they’re planning, for example, when they hibernate, but these behaviors are largely the result of instinct. It is not possible to teach your pet dog or cat the meaning of tomorrow, because they live in the present. Humans, however, are constantly preparing for the future and even for beyond our own life spans. We scheme and daydream—we can’t help it. Our brains are planning machines.
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Misc Quotes
Self-awareness: the ability to put one’s self inside a model of the environment, and then run simulations of this model into the future to achieve a goal.
“I have no special talents.… I am only passionately curious.”-Einstein.
“The true sign of intelligence is not knowledge, but imagination.”-Einstein.
“I have always maintained that, excepting fools, men do not differ much in intellect, only in zeal and hard work.”-Charles Darwin.
The children who exhibit delayed gratification scored higher on almost every measure of success in life: higher-paying jobs, lower rates of drug addiction, higher test scores, higher educational attainment, better social integration, etc.
Japan, with 21% of the population >65, is a train wreck in slow motion. Three demographic factors are at work. First, Japanese women have the longest life expectancy of any ethnic group in the world. Second, Japan has one of the world’s lowest birthrates. Third, it has a strict immigration policy, with over 99% of the population being pure Japanese.
Dualism: The brain and the soul are two separate entities.
The best way to prepare for a final exam is to mentally review the material periodically during the day, until the material becomes part of your long-term memory. Scientists theorize that we have a fixed amount of CREB activator in the brain that can limit the amount we can learn in any specific time. If we try to cram before a test, it means that we quickly exhaust the amount of CREB activators, and hence we cannot learn any more—at least until we take a break to replenish the CREB activators.
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Newtons Gravity & Einstein’s Space-Time
When Isaac Newton was puzzling over the motion of the moon, he created a simple model that would eventually change the course of human history: he envisioned throwing an apple in the air. The faster you threw the apple, he reasoned, the farther it would travel. If you threw it fast enough, in fact, it would encircle the Earth entirely, and might even return to its original point. Then, Newton claimed, this model represented the path of the moon, so the forces that guided the motion of the apple circling the Earth were identical to the forces guiding the moon. But the model, by itself, was still useless. The key breakthrough came when Newton was able to use his new theory to simulate the future, to calculate the future position of moving objects. This was a difficult problem, requiring him to create an entirely new branch of mathematics, called calculus. Using this new mathematics, Newton was then able to predict the trajectory of not just the moon, but also Halley’s Comet and the planets.
Einstein replaced Newton’s picture of forces acting on apples and moons with a new model based on a new parameter, the curvature of space and time. An apple moved not because the Earth exerted a force on it, but because the fabric of space and time was stretched by the Earth, so the apple was simply moving along the surface of a curved space-time. From this, Einstein could then simulate the future of the entire universe.
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Humans
The vast majority of our DNA is ‘Junk DNA’ that seemingly serves no purpose. This junk DNA slowly mutates at a known rate, ~1%/4million years. Since we differ from chimps in our DNA by ~1.5%, this means that we probably separated from the chimpanzees about six million years ago. Hence there is a “molecular clock” in each of our cells. And since evolution accelerates this mutation rate, analyzing where this acceleration took place allows you to tell which genes are driving evolution.
RIM-941: The only gene ever discovered that is found strictly in Homo sapiens and not in other primates.
There are three billion base pairs in our DNA, each one containing one of four nucleic acids, labeled A, T, C, G. Therefore, the total amount of information we can store in our DNA is four raised to the three-billionth power. But the brain can store much more information among its one hundred billion neurons, which can either fire or not fire. Hence, there are two raised to the one-hundred-billionth power possible initial states of the human brain.
Animals do not conjugate their verbs. So perhaps the ability to express the past and future tense was a key breakthrough in the development of intelligence.
The human body can muster only about one-fifth of a HP on average.
The human genome consists of roughly twenty-three thousand genes.
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Aging
Aging is the buildup of errors, at the genetic and cellular level. As cells get older, errors begin to build up in their DNA and cellular debris also starts to accumulate, which makes cells sluggish. As cells begin to slowly malfunction, skin begins to sag, bones become frail, hair falls out, and our immune system deteriorates. Eventually, we die.
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Human Brain
The brain consumes ~20W of power (the power of a dim lightbulb), around the maximum energy it can consume before the body becomes dysfunctional.
The brain is not a digital computer, but rather a neural network of some sort that constantly rewires itself after learning new tasks.
The brain is not a digital computer at all, but a highly sophisticated neural network of some sort. Unlike a digital computer, which has a fixed architecture (input, output, and processor), neural networks are collections of neurons that constantly rewire and reinforce themselves after learning a new task. The brain has no programming, no operating system, no Windows, no central processor. Instead, its neural networks are massively parallel, with one hundred billion neurons firing at the same time in order to accomplish a single goal: to learn.
Hypothalamus. Regulates body temperature, our circadian rhythm, hunger, thirst, and aspects of reproduction and pleasure. It lies below the thalamus—hence its name.
Hippocampus: Where all memories flow and are converted into long-term memories.
NR2B Gene: acts like a switch controlling the brain’s ability to associate one event with another.
Some suspect that, if your memory becomes too great, you also remember all the failures and hurts as well, perhaps making you hesitant. So there is also a potential downside to remembering too much.
CREB Gene: An activator which stimulates the formation of new connections between neurons.
GREB Gene: A repressor which suppresses the formation of new memories.
Scientists theorize that we have a fixed amount of CREB activator in the brain that can limit the amount we can learn in any specific time. If we try to cram before a test, it means that we quickly exhaust the amount of CREB activators, and hence we cannot learn any more—at least until we take a break to replenish the CREB activators.
Parietal lobe is located at the top of our brains. The right hemisphere controls sensory attention and body image; the left hemisphere controls skilled movements and some aspects of language. Damage to this area can cause many problems, such as difficulty in locating parts of your own body.
Occipital lobe: is located at the very back of the brain and processes visual information from the eyes. Damage to this area can cause blindness and visual impairment.
Temporal lobe: controls language (on the left side only). Damage to this lobe can leave us speechless or without the ability to recognize familiar faces.
Limbic System: Processing of emotions.
Emotion: It would take too much time and energy for a thoughtful analysis of every crisis, so the brain saves energy by making snap judgments in the form of emotions; determining what is important and what is not.
Emotions originate and are processed in the emotions are rapid-fire responses to emergencies from the limbic system that do not need permission from the prefrontal cortex.
Anterior Cingulate Cortex: Lies between the PFC and the Limbic System and links/processes emotion and rational thinking.
Dorsolateral PFC (the CEO of the Brain): Simulating the future, the heart of Level III consciousness, is mediated by the dorsolateral prefrontal cortex, the CEO of the brain, with competition between the pleasure center and the orbitofrontal cortex (which acts to check our impulses). The actual process of simulating the future takes place when the prefrontal cortex accesses the memories of the past in order to approximate future events.
Grey Matter: Consists of billions of tiny brain cells called neurons. Like a gigantic telephone network, they receive messages from other neurons via dendrites, which are like tendrils sprouting from one end of the neuron. At the other end of the neuron, there is a long fiber called the axon. Eventually the axon connects to as many as ten thousand other neurons via their dendrites. At the juncture between the two, there is a tiny gap called the synapse. These synapses act like gates, regulating the flow of information within the brain. Special chemicals called neurotransmitters can enter the synapse and alter the flow of signals. Because neurotransmitters like dopamine, serotonin, and noradrenaline help control the stream of information moving across the myriad pathways of the brain, they exert a powerful effect on our moods, emotions, thoughts, and state of mind.
Left Brain, Right Brain
Left Brain: Analytical and logical; where verbal skills are found.
Although consciousness is a patchwork of competing and often contradictory tendencies, the left brain ignores inconsistencies and papers over obvious gaps in order to give us a smooth sense of a single “I.” In other words, the left brain is constantly making excuses, some of them harebrained and preposterous, to make sense of the world. It is constantly asking “Why?” and dreaming up excuses even if the question has no answer.
Right Brain: Holistic and artistic.
Commands pass from the left brain to the right brain (where the final decision is made) via the corpus callosum.
Since the right brain cannot speak (the speech centers are located only in the left brain), it is difficult to get answers from the right brain. Dr. Gazzaniga told me that to find out what the right brain was thinking, he created an experiment in which the (mute) right brain could “talk” by using Scrabble letters. He began by asking the patient’s left brain what he would do after graduation. The patient replied that he wanted to become a draftsman. But things got interesting when the (mute) right brain was asked the same question. The right brain spelled out the words: “automobile racer.” Unknown to the dominant left brain, the right brain secretly had a completely different agenda for the future. The right brain literally had a mind of its own.
The two halves of the brain complement each other, offering pessimistic/optimistic or analytical/holistic analysis of the same idea.
Brain: Information Flow
Sensory Information (Vision, Touch, Taste) to Memory Formation: First pass through the brain stem and onto the thalamus, which acts like a relay station, directing the signals to the various sensory lobes of the brain, where they are evaluated. The processed information reaches the prefrontal cortex, where it enters our consciousness and forms what we consider our short-term memory, which can range from several seconds to minutes. To store these memories for a longer duration, the information must then run through the hippocampus, where memories are broken down into different categories. Rather than storing all memories in one area of the brain like a tape recorder or hard drive, the hippocampus redirects the fragments to various cortices. (Storing memories in this way is actually more efficient than storing them sequentially. If human memories were stored sequentially, like on computer tape, a vast amount of memory storage would be required. In fact, in the future, even digital storage systems may adopt this trick from the living brain, rather than storing whole memories sequentially.) For instance, emotional memories are stored in the amygdala, but words are recorded in the temporal lobe. Meanwhile, colors and other visual information are collected in the occipital lobe, and the sense of touch and movement reside in the parietal lobe.
Memory Reproduction: There are electromagnetic vibrations oscillating across the entire brain at roughly 40 cycles/s, which can be picked up by EEG scans. One fragment of memory might vibrate at a very precise frequency and stimulate another fragment of memory stored in a distant part of the brain. Previously it was thought that memories might be stored physically close to one another, but this new theory says that memories are not linked spatially but rather temporally, by vibrating in unison. If this theory holds up, it means that there are electromagnetic vibrations constantly flowing through the entire brain, linking up different regions and thereby re-creating entire memories. Hence the constant flow of information between the hippocampus, the prefrontal cortex, the thalamus, and the different cortices might not be entirely neural after all. Some of this flow may be in the form of resonance across different brain structures.
Imagine you have the urge to wash your hands. The orbitofrontal cortex recognizes that something is wrong, that your hands are dirty. The caudate nucleus kicks in and causes you to automatically wash your hands. Then the cingulate cortex registers satisfaction that your hands are clean.
Images of a park, for example, are sent to the occipital cortex in the back of the brain, while the sense of touch from the wind is sent to the parietal lobe. The signals are processed in appropriate cortices, and then sent to the prefrontal cortex, where we finally become conscious of all these sensations.
There are roughly 130 million cells in the eye’s retina, called cones and rods; they process and record 100 million bits of information from the landscape at any time. This vast amount of data is then collected and sent down the optic nerve, which transports 9 million bits of information per second, and on to the thalamus. From there, the information reaches the occipital lobe, at the very back of the brain. This visual cortex, in turn, begins the arduous process of analyzing this mountain of data. The visual cortex consists of several patches at the back of the brain, each of which is designed for a specific task. They are labeled V1 to V8. Remarkably, the area called V1 is like a screen; it actually creates a pattern on the back of your brain very similar in shape and form to the original image. This image bears a striking resemblance to the original, except that the very center of your eye, the fovea, occupies a much larger area in V1 (since the fovea has the highest concentration of neurons). The image cast on V1 is therefore not a perfect replica of the landscape but is distorted, with the central region of the image taking up most of the space. Besides V1, other areas of the occipital lobe process different aspects of the image, including: • Stereo vision. These neurons compare the images coming in from each eye. This is done in area V2. • Distance. These neurons calculate the distance to an object, using shadows and other information from both eyes. This is done in area V3. • Colors are processed in area V4. • Motion. Different circuits can pick out different classes of motion, including straight-line, spiral, and expanding motion. This is done in area V5. More than thirty different neural circuits involved with vision have been identified, but there are probably many more. From the occipital lobe, the information is sent to the prefrontal cortex, where you finally “see” the image and form your short-term memory. The information is then sent to the hippocampus, which processes it and stores it for up to twenty-four hours. The memory is then chopped up and scattered among the various cortices.
Convergent and Divergent Thinking
The left hemisphere is responsible for convergent thinking and the right hemisphere for divergent thinking. The left side examines details and processes them logically and analytically but lacks a sense of overriding, abstract connections. The right side is more imaginative and intuitive and tends to work holistically, integrating pieces of an informational puzzle into a whole.”-Dr. Ulrich Kraft of Fulda, Germany.
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The Brain & Sleep
Dreams might reflect “house cleaning,” in which the brain tries to organize its memories in a more coherent way.
The hippocampus is active when we dream, suggesting that dreams draw upon our storehouse of memories. The amygdala and anterior cingulate are also active, meaning that dreams can be highly emotional, often involving fear.
As we go to sleep, the brain stem activates another system, the cholinergic, which emits chemicals that put us in a dream state. As we dream, cholinergic neurons in the brain stem begin to fire, setting off erratic pulses of electrical energy called PGO (pontine-geniculate-occipital) waves. These waves travel up the brain stem into the visual cortex, stimulating it to create dreams. Cells in the visual cortex begin to resonate hundreds of times per second in an irregular fashion, which is perhaps responsible for the sometimes-incoherent nature of dreams. This system also emits chemicals that decouple parts of the brain involved with reason and logic. The lack of checks coming from the prefrontal and orbitofrontal cortices, along with the brain becoming extremely sensitive to stray thoughts, may account for the bizarre, erratic nature of dreams.
Lucid Dreaming: dreamers are aware that they are dreaming and can consciously control the direction of the dream.
Anyone can learn to do lucid dreaming by practicing certain techniques. In particular, people who do lucid dreaming should keep a notebook of dreams. Before going to sleep, they should remind themselves that they will “wake up” in the middle of the dream and realize that they are moving in a dream world. It is important to have this frame of mind before hitting the pillow.
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The Brain & Drugs
Drugs first penetrate the blood-brain barrier (prevents most harmful chemicals in the bloodstream from entering the brain) and then cause the overproduction of neurotransmitters like dopamine, which then floods the nucleus accumbens, a tiny pleasure center located deep in the brain near the amygdala. The dopamine, in turn, is produced by certain brain cells in the ventral tegmental area, called VTA cells. All drugs basically work the same way: by crippling the VTA–nucleus accumbens circuit, which controls the flow of dopamine and other neurotransmitters to the pleasure center. Drugs differ only in the way in which this process takes place. There are at least three main drugs that stimulate the pleasure center of the brain: dopamine, serotonin, and noradrenaline; all of them give feelings of pleasure, euphoria, and false confidence, and also produce a burst of energy.
Cocaine and other stimulants, for example, work in two ways.
First, they directly stimulate the VTA cells to produce more dopamine, hence causing excess dopamine to flood into the nucleus accumbens.
Second, they prevent the VTA cells from going back to their “off” position, thus keeping them continually producing dopamine. They also impede the uptake of serotonin and noradrenaline. The simultaneous flooding of neural circuits from all three of these neurotransmitters, then, creates the tremendous high associated with cocaine.
Heroin and other opiates, by contrast, work by neutralizing the cells in the VTA that can reduce the production of dopamine, thus causing the VTA to overproduce dopamine.
Drugs like LSD operate by stimulating the production of serotonin, inducing a feeling of well-being, purpose, and affection. But they also activate areas of the temporal lobe involved in creating hallucinations. (Only 50 micrograms of LSD can cause hallucinations. LSD binds so tightly, in fact, that further increasing the dosage has no effect.
The blood-brain barrier: prevents most harmful chemicals in the bloodstream from entering the brain.
Na pentathol depresses activity in the PFC, so that a person becomes more relaxed, talkative, and uninhibited. However, this does not mean that they tell the truth. On the contrary, people under the influence of Na pentathol, like those who have imbibed a few too many, are fully capable of lying. The “secrets” that come spilling out of the mouth of someone under this drug may be total fabrications, so even the CIA eventually gave up on drugs like this.
Brave New World: The elite control society by flooding it with mind-altering drugs, free love, and constant brainwashing. In this way, peace, tranquility, and harmony are maintained, but the novel asked a disturbing question that resonates even today: How much of our freedom and basic humanity do we want to sacrifice in the name of peace and social order?
Studies in animals demonstrate how powerful drug addiction is: rats, mice, and primates will, given the chance, take drugs like cocaine, heroin, and amphetamines until they drop from exhaustion or die from it.
Dopamine, because it is so essential for the synapses of the brain, has been implicated in other disorders as well. One theory holds that Parkinson’s disease is aggravated by a lack of dopamine in the synapses, while Tourette’s syndrome can be triggered by an overabundance of it.
“The brain’s gonna do what the brain’s gonna do, but you don’t have to let it push you around.” These drugs are certainly not a cure, but they have brought some relief to the sufferers.
MRI scans of the brains of meth addicts show an 11% reduction in the size of the limbic system, which processes emotions, and an 8% loss of tissue in the hippocampus, which is the gateway for memory. MRI scans show that the damage in some ways is comparable to that found in Alzheimer’s patients. But no matter how much meth destroys the brain, addicts crave it because its high is up to twelve times the rush caused by eating a delicious meal or even having sex.
Marijuana: The drug got a thumbs-down from the President’s Council on Bioethics. Its report concluded that “dulling our memory of terrible things [would] make us too comfortable with the world, unmoved by suffering, wrongdoing, or cruelty.… Can we become numb to life’s sharpest sorrows without also becoming numb to its greatest joys?”
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Free Will?
It is safe to say that more and more neuroscientists are gradually coming to the conclusion that free will does not exist, at least not in the usual sense. If certain bizarre behaviors can be linked to precise defects in the brain, then a person is not scientifically responsible for the crimes he might commit.
Decisions are made ahead of time by the brain, without the input of consciousness, and then later the brain tries to cover this up (as it’s wont to do) by claiming that the decision was conscious.
The question is: Are all our actions also determined? These questions have philosophical and theological implications. For example, most religions adhere to some form of determinism and predestination. Since God is omnipotent, omniscient, and omnipresent, He knows the future, and hence the future is determined ahead of time. He knows even before you are born whether you will go to Heaven or Hell.
The Catholic Church split in half on this precise question during the Protestant revolution. According to Catholic doctrine at that time, one could change one’s ultimate fate with an indulgence, usually by making generous financial donations to the Church. In other words, determinism could be altered by the size of your wallet. Martin Luther specifically singled out the corruption of the Church over indulgences when he tacked his 95 Theses on the door of a church in 1517, triggering the Protestant Reformation. This was one of the key reasons why the Church split down the middle, causing casualties in the millions and laying waste to entire regions of Europe.
So it seems we have a problem. On one hand, quantum mechanics and chaos theory claim that the universe is not predictable, and therefore, free will seems to exist. But a reverse-engineered brain, made of transistors, would by definition be predictable. Since the reverse-engineered brain is theoretically identical to a living brain, then the human brain is also deterministic and there is no free will. Clearly, this contradicts the first statement.
The brain, they argue, is a quantum device, not just a collection of transistors. Hence this project is doomed to fail. In this camp is Oxford physicist Dr. Roger Penrose, an authority on Einstein’s theory of relativity, who claims that it is quantum processes that may account for the consciousness of the human brain. Penrose starts by saying that mathematician Kurt Gödel has proven that arithmetic is incomplete; that is, that there are true statements in arithmetic that cannot be proven using the axioms of arithmetic. Similarly, not only is mathematics incomplete, but so is physics. He concludes by stating that the brain is basically a quantum mechanical device and there are problems that no machine can solve because of Gödel’s incompleteness theorem. Humans, however, can make sense of these conundrums using intuition.
We are just wetware, running software called the mind, nothing more or less.
Strict Determinism is destroyed by a subtle combination of quantum effects and chaos theory.
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Consciousness
Consciousness: The process of creating a model of the world using multiple feedback loops in various parameters (e.g., in temperature, space, time, and in relation to others), in order to accomplish a goal (e.g., find mates, food, shelter).
Space-time theory of consciousness: Animals create a model of the world mainly in relation to space, and to one another, while humans go beyond and create a model of the world in relation to time, both forward and backward.
Level 0: The lowest level of consciousness, where an organism is stationary or has limited mobility and creates a model of its place using feedback loops in a few parameters (e.g., temperature).
Describes thermostats and plants and involves a few feedback loops in a handful of simple parameters such as temperature or sunlight.
Level I: Organisms that are mobile and have a CNS, which includes a new set of parameters to measure their changing location.
One example of Level I consciousness would be reptiles. They have so many feedback loops that they developed a central nervous system to handle them.
Describes insects and reptiles, which are mobile and have a central nervous system; it involves creating a model of your world in relationship to a new parameter, space.
Level II: Consciousness in which organisms create a model of their place not only in space but also with respect to others (i.e., they are social animals with emotions).
Level II consciousness coincides with the formation of new structures of the brain in the form of the limbic system. As noted earlier, the limbic system includes the hippocampus (for memories), amygdala (for emotions), and the thalamus (for sensory information), all of which provide new parameters for creating models in relation to others. The number and type of feedback loops therefore change.
Creates a model of the world in relationship to others of its kind, requiring emotions.
Level III: Consciousness in which there are so many feedback loops that we need a CEO to sift through them in order to simulate the future and make a final decision. Accordingly, our brains differ from those of other animals, especially in the expanded prefrontal cortex, located just behind the forehead, which allows us to “see” into the future.
Describes humans, who incorporate time and self-awareness to simulate how things will evolve in the future and determine our own place in these models.
Human consciousness is a specific form of consciousness that creates a model of the world and then simulates it in time, by evaluating the past to simulate the future. This requires mediating and evaluating many feedback loops in order to make a decision to achieve a goal.
Dorsolateral PFC: Simulates the Future, the CEO of the Brain.
“The difference between man and the higher animals, great as it is, is certainly one of degree and not of kind.”-Charles Darwin.
Gossiping is essential for survival because the complex mechanics of social interactions are constantly changing, so we have to make sense of this ever-shifting social terrain. This is Level II consciousness at work. But once we hear a piece of gossip, we immediately run simulations to determine how this will affect our own standing in the community, which moves us to Level III consciousness.
Different states of consciousness vibrate at different frequencies. For example, deep sleep corresponds to delta waves, which vibrate at .1 to 4 cycles per second. Active mental states, such as problem solving, correspond to beta waves, vibrating from 12 to 30 cycles per second.
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Brain Scan Technology
Magnetic Resonance Imagery (MRI)
MRI machines work as follows: Patients lie flat and are inserted into a cylinder containing two large coils, which create the magnetic field. When the magnetic field is turned on, the nuclei of the atoms inside your body act very much like a compass needle: they align horizontally along the direction of the field. Then a small pulse of radio energy is generated, which causes some of the nuclei in our body to flip upside down. When the nuclei later revert back to their normal position, they emit a secondary pulse of radio energy, which is then analyzed by the MRI machine. By analyzing these tiny “echoes,” one can then reconstruct the location and nature of these atoms.
Physicists estimate that, with increasing computer power, an MRI machine of the future might be the size of a cell phone. The raw data from this cell phone would be sent wirelessly to a supercomputer, which would process the data from the weak magnetic field and then create a 3-D image. (The weakness of the magnetic field is compensated for by the increase in computer power.) This then could vastly accelerate research.
Electro-Encephalogram (EEG):
To use the EEG machine, the patient usually puts on a futuristic-looking helmet with scores of electrodes on the surface. (More advanced versions place a hairnet over the head containing a series of tiny electrodes.) These electrodes detect the tiny electrical signals that are circulating in the brain. An EEG scan differs from an MRI scan in several crucial ways. The MRI scan, as we have seen, shoots radio pulses into the brain and then analyzes the “echoes” that come back. This means you can vary the radio pulse to select different atoms for analysis, making it quite versatile. The EEG machine, however, is strictly passive; that is, it analyzes the tiny electromagnetic signals the brain naturally emits. The EEG excels at recording the broad electromagnetic signals that surge across the entire brain, which allows scientists to measure the overall activity of the brain as it sleeps, concentrates, relaxes, dreams, etc.
Positron Emission Topography (PET):
The PET scan calculates the flow of energy in the brain by locating the presence of glucose, the sugar molecule that fuels cells.
PET scans make use of the subatomic particles emitted from Na-22 within the glucose. To start the PET scan, a special solution containing slightly radioactive sugar is injected into the patient. The sodium atoms inside the sugar molecules have been replaced by radioactive Na-22 atoms. Every time a sodium atom decays, it emits a positive electron, or positron, which is easily detected by sensors. By following the path of the radioactive Na atoms in sugar, one can then trace out the energy flow within the living brain. The PET scan shares many of the same advantages of MRI scans but does not have the fine spatial resolution of an MRI photo. However, instead of measuring blood flow, which is only an indirect indicator of energy consumption in the body, PET scans measure energy consumption, so it is more closely related to neural activity.
Optogenetics
Allows you to activate certain pathways of the brain controlling behavior by shining a light beam on the brain. Incredibly, a light-sensitive gene that causes a cell to fire can be inserted, with surgical precision, directly into a neuron. Then, by turning on a light beam, the neuron is activated. More importantly, this allows scientists to excite these pathways, so that you can turn on and off certain behaviors by flicking a switch.
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Brain Disorders & Deterioration
Mental Illness: Largely caused by the disruption of the delicate checks and balances between competing feedback loops that simulate the future (usually because one region of the brain is overactive or underactive). Because the CEO of the mind (the dorsolateral prefrontal cortex) no longer has a balanced assessment of the facts, due to this disruption in feedback loops, it begins to make strange conclusions and act in bizarre ways. There are two general types of Mental Illness:
Mental disorders involving injury to the brain; Parkinson’s, Epilepsy, Alzheimer’s, and a wide variety of disorders caused by strokes and tumors, in which brain tissue is actually injured or malfunctioning.
In the case of Parkinson’s and epilepsy, there are neurons in a precise area of the brain that are overactive.
In Alzheimer’s, a buildup of amyloid plaque destroys brain tissue, including the hippocampus.
In strokes and tumors, certain parts of the brain are silenced, causing numerous behavioral problems. Each of these disorders has to be treated differently, since each injury is different.
Neuroscientists have noticed a link between damage to the brain’s left hemisphere and negative moods, including depression and uncontrollable crying. Damage to the right, however, has been associated with a broad array of positive emotions.
“Anterograde amnesia” occurs when short-term memory is damaged, so the person has difficulty forming new memories after the event that caused the amnesia.
Mental disorders triggered by incorrect wiring within the brain; schizophrenia, OCD, Depression, Bipolar Disporder.
Each region of the brain may be relatively healthy and intact, but one or more of them may be miswired, causing messages to be processed incorrectly. This category is difficult to treat, since the wiring of the brain is not well understood. So far, the main way to deal with these disorders is through drugs that influence neurotransmitters, but there is still a lot of hit or miss involved here.
Bipolar disorder: a person suffers from extreme bouts of wild, delusional optimism, followed by a crash and then periods of deep depression. The drug Li seems to control many of the symptoms of bipolar disorder.
One theory states that bipolar disorder may be caused by an imbalance between the left and right hemispheres.
1 in 40 Americans suffers from OCD.
Alzheimer’s
5% of people from age 65-74 have Alzheimer’s, but more than 50% of those over 85 have it, even if they have no obvious risk factors.
In the early stages of Alzheimer’s, the hippocampus, the part of the brain through which memories are processed, begins to deteriorate. Indeed, brain scans clearly show that the hippocampus shrinks in Alzheimer’s patients, but the wiring linking the prefrontal cortex to the hippocampus also thins, leaving the brain unable to properly process short-term memories. Long-term memories already stored throughout the cortices of the brain remain relatively intact, at least at first. This creates a situation where you may not remember what you just did a few minutes ago but can clearly recall events that took place decades ago. Eventually, the disease progresses to the point where even basic long-term memories are destroyed. The person is unable to recognize their children or spouse and to remember who they are, and can even fall into a comalike vegetative state.
2012: Research revealed that Alzheimer’s begins with the formation of tau amyloid proteins, which in turn accelerates the formation of beta amyloid, a gummy, gluelike substance that clogs up the brain.
What makes these amyloid plaques so difficult to target with drugs is that they are most likely made of “prions,” which are misshapen protein molecules. They are not bacteria or viruses, but nevertheless they can reproduce. When viewed atomically, a protein molecule resembles a jungle of ribbons of atoms tied together. This tangle of atoms must fold onto itself correctly for the protein to assume the proper shape and function. But prions are misshapen proteins that have folded incorrectly. Worse, when they bump into healthy proteins, they cause them to fold incorrectly as well. Hence one prion can cause a cascade of misshapen proteins, creating a chain reaction that contaminates billions more.
In some sense, depression is the price we pay for being able to simulate the future. Our consciousness has the ability to conjure up all sorts of horrific outcomes for the future, and is therefore aware of all the bad things that could happen, even if they are not realistic.
2012: Scientists from the Harvard Medical School and Massachusetts General Hospital analyzed sixty thousand people worldwide and found that there was a genetic link between five major mental illnesses: schizophrenia, bipolar disorder, autism, major depression, and attention deficit hyperactivity disorder (ADHD). Together they represent a significant fraction of all mentally ill patients. After an exhaustive analysis of the subjects’ DNA, scientists found that four genes increased the risk of mental illness. Two of them involved the regulation of Ca channels in neurons. (Ca is an essential chemical involved in the processing of neural signals.)
Sea Sickness: Many people develop sea sickness when they are on a rocking boat because their eyes, looking at the cabin walls, tell them that they are stationary, but their inner ear tells them that they are swaying. The mismatch between these signals causes them to become nauseous. The remedy is to look out at the horizon so that the visual image matches the signals from the inner ear.
“There’s not a single neurological disease today in which anybody knows what is malfunctioning in this circuit—which pathway, which synapse, which neuron, which receptor. This is shocking.”
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Brain- Modern Medicine
Modern medicine has given us a variety of new possibilities and therapies to tackle Brain disorders:
Finding new neurotransmitters and new drugs that regulate the signaling of neurons.
Locating the genes linked to various mental illnesses, and perhaps using gene therapy.
Using deep brain stimulation to dampen or increase neural activity in certain areas.
Using EEG, MRI, MEG, and TES to understand precisely how the brain malfunctions.
Brain Imaging.
EyeWire: https://eyewire.org/explore
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Evolving Intelligence
There were at least three basic ingredients that set the stage for our becoming intelligent:
The opposable thumb, which gives us the ability to manipulate and reshape our environment via tools.
Stereo eyes or the 3-D eyes of a hunter.
Language, which allows us to accumulate knowledge, culture, and wisdom across generations.
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Increasing Intelligence
There are several ways in which one can increase the intelligence of the brain using the laws of physics, but each has its own problems:
One can increase brain size and extend the length of neurons. The problem here is that the brain now consumes more energy. This generates more heat in the process, which is detrimental to our survival. If the brain uses up more energy, it gets hotter, and tissue damage results if the body temperature becomes too high. (The chemical reactions of the human body and our metabolism require temperatures to be in a precise range.) Also, longer neurons means that it takes longer for signals to go across the brain, which slows down the thinking process.
One can pack more neurons into the same space by making them thinner. But if neurons become thinner and thinner, the complex chemical/electrical reactions that must take place inside the axons fail, and eventually they begin to misfire more easily. Douglas Fox, writing in Scientific American, says, “You might call it the mother of all limitations: the proteins that neurons use to generate electrical pulses, called ion channels, are inherently unstable.”
One can increase the speed of the signal by making the neurons thicker. But this also increases energy consumption and generates more heat. It also increases the size of the brain, which increases the time it takes for the signals to reach their destination.
One can add more connections between neurons. But this again increases energy consumption and heat generation, making the brain larger and slower in the process.
So each time we tinker with the brain, we are checkmated. The laws of physics seem to indicate that we have maxed out the intelligence that we humans can attain in this way.
If we are to increase our intelligence, it has to be done by making our brains more efficient (via drugs, genes, and possibly TES-type machines).
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Brain Enhancements
Learning New Skills and Hippocampus Cells: It turns out that thousands of new hippocampus cells are born naturally each day, but most die soon afterward. However, it was shown that rats that learned new skills retained more of their new cells. A combination of exercise and mood-elevating chemicals can also boost the survival rate of new hippocampus cells. It turns out that stress, on the contrary, accelerates the death of new neurons.
It is possible that we can enhance or alter our mental capabilities via telepathy, telekinesis, uploading memories, or brain boosts. Such enhancement basically means modifying and augmenting the mental capabilities of our consciousness.
Using the power of their mind, handicapped humans may be able to communicate with loved ones, control their wheelchairs and beds, walk by mentally guiding mechanical limbs, manipulate household appliances, and lead semi-normal lives. But in the long term, these advances could have profound economic and practical implications for the world. By mid-century, it could become commonplace to interact with computers directly with the mind.
Altering our genes in this way would require no more than a simple shot in the arm. A harmless virus would then enter our blood, which would then infect normal cells by injecting its genes. Once the “smart gene” is successfully incorporated into our cells, the gene becomes active and releases proteins that would increase our memory and cognitive skills by affecting the hippocampus and memory formation. If the insertion of genes becomes too difficult, another possibility is to insert the proper proteins directly into the body, bypassing the use of gene therapy. Instead of getting a shot, we would swallow a pill.
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Computing
Today the smallest layer of Si in your Pentium chip is about twenty atoms in width, and by 2020 that layer might be five atoms across.
Leakage and heat will eventually doom Moore’s law, and a replacement will soon be necessary.
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Artificial Intelligence
There are at least two basic problems confronting AI: pattern recognition and common sense.
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Robotics
It is crucial that robots be programmed to distinguish between what is important and what is not, and emotions are shortcuts the human brain uses to rapidly determine this.
IBMs Watson can process data at the astonishing rate of 500 Gbs (~ one million books per second) with 16 Tb of RAM memory. It also had access to two hundred million pages of material in its memory, including the entire storehouse of knowledge within Wikipedia.
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Space Exploration
Dangers of Space Travel
Micrometeorites
Skeletal loss due to the effects of prolonged weightlessness. After just a few months in weightlessness, the body loses a large fraction of its calcium and minerals, leaving the astronauts incredibly weak.
Problems associated with adjusting to different gravity fields.
Roche Limit: The distance at which moons get ripped apart by tidal forces.
The rings of Saturn lie exactly at the Roche limit, so they might have been caused by a moon that wandered too close to the mother planet.
The Hubble Space Telescope has given us an estimate of the total number of galaxies in the visible universe: one hundred billion. Therefore, we can calculate the number of earthlike planets in the visible universe: one billion times one hundred billion, or one hundred quintillion earthlike planets.
Our first contact with an alien civilization will probably not begin with a flying saucer landing on the White House lawn. More likely, it will happen when some teenager, running a screen saver from the SETI@home project, announces that his or her PC has decoded signals from the Arecibo radio telescope in Puerto Rico. Or perhaps when the SETI project at Hat Creek detects a message that indicates intelligence. Our first encounter will therefore be a one-way event. We will be able to eavesdrop on intelligent messages, but a return message may take decades or centuries to reach them.
2001: A Space Odyssey, which even today represents the most plausible encounter with an extraterrestrial civilization.
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Magnetic Fields
Objects made of plastic, water, or wood can easily pass through magnetic fields.
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Chronology
2012: Research revealed that Alzheimer’s begins with the formation of tau amyloid proteins, which in turn accelerates the formation of beta amyloid, a gummy, gluelike substance that clogs up the brain.
2012: Scientists from the Harvard Medical School and Massachusetts General Hospital analyzed sixty thousand people worldwide and found that there was a genetic link between five major mental illnesses: schizophrenia, bipolar disorder, autism, major depression, and attention deficit hyperactivity disorder (ADHD). Together they represent a significant fraction of all mentally ill patients. After an exhaustive analysis of the subjects’ DNA, scientists found that four genes increased the risk of mental illness. Two of them involved the regulation of Ca channels in neurons. (Ca is an essential chemical involved in the processing of neural signals.)-Future of the Mind by Kaku.
1978: Louise Brown, the first test-tube baby is born.
1967: Dr. Paul MacLean of the National Institute of Mental Health applied Charles Darwin’s theory of evolution to the brain. He divided the brain into three parts. (Since then, studies have shown that there are refinements to this model, but we will use it as a rough organizing principle to explain the overall structure of the brain.) First, he noticed that the back and center part of our brains, containing the brain stem, cerebellum, and basal ganglia, are almost identical to the brains of reptiles. Known as the “reptilian brain,” these are the oldest structures of the brain, governing basic animal functions such as balance, breathing, digestion, heartbeat, and blood pressure. They also control behaviors such as fighting, hunting, mating, and territoriality, which are necessary for survival and reproduction.-Future of the Mind by Kaku.
1960: Astronomer Frank Drake initiates the Search for Extraterrestrial Intelligence (SETI) known as Project Ozma (after the Queen of Oz); using a 25m radio telescope in Green Bank, WV.
1957: The Defense Advanced Research Projects Agency (DARPA) is established by President Dwight Eisenhower after the Russians sent Sputnik into orbit and shocked the world. Realizing that the United States might quickly be outpaced by the Soviets in high technology, Eisenhower hastily established this agency to keep the country competitive with the Russians. Over the years, the numerous projects it started grew so large that they became independent entities by themselves. One of its first spinoffs was NASA. DARPA’s strategic plan reads like something from science fiction: its “only charter is radical innovation.” The only justification for its existence is “to accelerate the future into being.”-Future of the Mind by Kaku.
1989: Inlight of the breakup of the Soviet Bloc, the National Science Foundation decides it was unnecessary to keep it a secret, so it declassified this hush-hush military technology and essentially gave codes and blueprints away for free. Arpanet would eventually become the Internet.
1960’s: One of DARPAs early projects was Arpanet, which was a war-fighting telecommunications network that would electronically connect scientists and officials during and after World War III. In 1989, the National Science Foundation decided that, in light of the breakup of the Soviet bloc, it was unnecessary to keep it a secret, so it declassified this hush-hush military technology and essentially gave codes and blueprints away for free. Arpanet would eventually become the Internet.
24 Apr, 1957: Project 57 is initiated by DARPA when the U.S. Air Force needed a way to guide its ballistic missiles in space; a top-secret project that was designed to place H-bombs on hardened Soviet missile silos in a thermonuclear exchange. It would later become the foundation for the Global Positioning System (GPS). Instead of guiding missiles, today it guides lost motorists.
1953-1973: CIA Project ‘MKULTRA’ begins to explore bizarre, fringe ideas.
1977: A cache of 20,000 documents survived the 1973 purge and were declassified under the Freedom of Information Act, revealing the full scope of MKULTRA.
It is now known that, from 1953 to 1973, MULTRA funded 80 institutions, including 44 universities and colleges, and scores of hospitals, pharmaceutical companies, and prisons, often experimenting on unsuspecting people without their permission, in 150 secret operations. At one point, fully 6% of the entire CIA budget went into MKULTRA. Some of these mind-control projects included:
Developing a “truth serum” so prisoners would spill their secrets.
Erasing memories via a U.S. Navy project called “Subproject 54.”
Using hypnosis and a wide variety of drugs, especially LSD, to control behavior.
Investigating the use of mind-control drugs against foreign leaders, e.g., Fidel Castro.
Perfecting a variety of interrogation methods against prisoners.
Developing a knockout drug that was fast working and left no trace.
Altering people’s personality via drugs to make them more pliable.
1973: CIA Director Richard Helms cancels MKULTRA during the Watergate scandal, hurriedly ordering all documents pertaining to the project destroyed.
11 Dec, 1951: French Chemist Paul Charpentier accidentally discovers antipsychotic drugs including Thorazine while searching for drugs that could be used in general anesthesia. Thorazine, specifically ‘Chlorpromazine’ help to alleviate the ‘voices’ that schizophrenics hear by regulating the level of certain neurotransmitters, such as dopamine. Specifically, the theory is that these drugs block the functioning of D2 receptors of certain nerve cells, thereby reducing the level of dopamine.
1949: Antonio Moniz wins the Nobel Prize for perfecting the lobotomy.
In total, it is estimated that 40,000 lobotomies were performed in the US alone over two decades.
1925: Schrödinger put forward his celebrated wave equation, which bears his name and is one of the most important equations ever written. It was an instant sensation, and won him the Nobel Prize in 1933. The Schrödinger equation accurately described the wavelike behavior of electrons and, when applied to the H atom, explained its strange properties. Miraculously, it could also be applied to any atom and explain most of the features of the periodic table of elements.-Future of the Mind by Kaku.
So the wave function of Schrödinger actually described the probability of finding the electron. Scientists had spent thousands of years painfully trying to eliminate chance and probabilities in their work, and now Heisenberg was allowing it in through the back door. The new philosophy can be summed up as follows: the electron is a point particle, but the probability of finding it is given by a wave. And this wave obeys Schrödinger’s equation and gives rise to the uncertainty principle.
But then physicists began to ask a problematic question that resonates even today: If the electron is described by a wave equation, then what is waving?
1927: Werner Heisenberg proposed a new principle that split the physics community down the middle. Heisenberg’s celebrated uncertainty principle states that you cannot know both the location and the momentum of an electron with certainty. This uncertainty was not a function of how crude your instruments were but was inherent in physics itself. Even God or some celestial being could not know the precise location and momentum of an electron.
1935: Schrödinger’s Cat; to demolish the quantum physicists once and for all, Schrödinger proposed his celebrated cat problem. Place a cat in a sealed box, with a container of poison gas. In the box, there is a lump of U. The U atom is unstable and emits particles that can be detected by a Geiger counter. The counter triggers a hammer, which falls and breaks the glass, releasing the gas, which can kill the cat. How do you describe the cat? A quantum physicist would say that the U atom is described by a wave, which can either decay or not decay. Therefore you have to add the two waves together. If the U fires, then the cat dies, so that is described by one wave. If the U does not fire, then the cat lives, and that is also described by a wave. To describe the cat, you therefore have to add the wave of a dead cat to the wave of a live cat. This means that the cat is neither dead nor alive! The cat is in a netherworld, between life and death, the sum of the wave describing a dead cat with the wave of a live cat. This is the crux of the problem, which has reverberated in the halls of physics for almost a century. So how do you resolve this paradox? There are at least three ways (and hundreds of variations on these three).-Future of the Mind by Kaku.
The Copenhagen interpretation (proposed by Bohr and Heisenberg): It says that to determine the state of the cat, you must open the box and make a measurement. The cat’s wave (which was the sum of a dead cat and a live cat) now “collapses” into a single wave, so the cat is now known to be alive (or dead). Thus, observation determines the existence and state of the cat. The measurement process is thus responsible for two waves magically dissolving into a single wave. Einstein hated this. For centuries, scientists have battled something called “solipsism” or “subjective idealism,” which claims that objects cannot exist unless there is someone there to observe them. Only the mind is real—the material world exists only as ideas in the mind. Thus, say the solipsists (such as Bishop George Berkeley), if a tree falls in the forest but no one is there to observe it, perhaps the tree never fell.
Objective Reality Theory (proposed by Einstein who thought the Copenhagen Interpretation was nonsense): the universe exists in a unique, definite state independent of any human observation. It is the commonsense view of most people. Objective reality goes back to Isaac Newton. In this scenario, the atom and subatomic particles are like tiny steel balls, which exist at definite points in space and time. There is no ambiguity or chance in locating the position of these balls, whose motions can be determined by using the laws of motion.
1920: The word “robot,” first appears from the Czech word for “worker,” in a 1920 play R.U.R. (Rossum’s Universal Robots) by Karel Capek, in which scientists create a new race of mechanical beings that look identical to humans.-Future of the Mind by Kaku.
1916: An updated IQ Exam is pioneered by Dr. Lewis Terman of Stanford University drawing on the earlier work of Binet and Simon.
1904: The first IQ exam is pioneered by French academics Alfred Binet & Theodore Simon.
1900: Life expectancy in the United States back then was forty-nine years. Many children died in infancy. Communicating with a neighbor involved yelling out the window. The mail was delivered by horse, if it came at all. Medicine was largely snake oil. The only treatments that actually worked were amputations (without anesthetics) and morphine to deaden the pain. Food rotted within days. Plumbing was nonexistent. Disease was a constant threat. And the economy could support only a handful of the rich and a tiny middle class.-Future of the Mind by Kaku.
1864: During the Prusso-Danish War, German doctor Gustav Fritsch treated many soldiers with gaping wounds to the brain and happened to notice that when he touched one hemisphere of the brain, the opposite side of the body often twitched. Later Fritsch systematically showed that, when he electrically stimulated the brain, the left hemisphere controlled the right side of the body, and vice versa. This was a stunning discovery, demonstrating that the brain was basically electrical in nature and that a particular region of the brain controlled a part on the other side of the body.-Future of the Mind by Kaku.
1532: Nicolaus Copernicus completes the first manuscript of his book “De Revolutionibus Orbium Coelestium” (On the Revolutions of the Heavenly Spheres), establishing that the planets orbit the sun rather than the Earth; i.e. the Earth is not the center of the Universe.-Future of the Mind by Kaku.
1517: Martin Luther triggers the Protestant Reformation, singling out the Catholic Church for corruption over indulgences when he tacks his 95 theses on the door of a Catholic Church.
1337-1453: The 100 Years War is fought between France & England.
Northern France was decimated by English troops and the French monarchy was in retreat, a young girl named Joan of Arc from Orléans claimed to have divine instructions to lead the French army to victory. With nothing to lose, Charles VII allowed her to command some of his troops. To everyone’s shock and wonder, she scored a series of triumphs over the English.
1431: Joan of Arc, after an elaborate interrogation, is found guilty of heresy and burned at the stake at the age of 19.-Future of the Mind by Kaku.
6 Ma: Humans evolve from Chimpanzees.
200 Ma: Evolution of the Cerebral Cortex, the third and most recent region of the mammalian brain, the cerebral cortex, which is the outer layer of the brain. The latest evolutionary structure within the cerebral cortex is the neocortex (meaning “new bark”), which governs higher cognitive behavior. It is most highly developed in humans: it makes up 80 percent of our brain’s.-Future of the Mind by Kaku.
250 Ma: Evolution of the Mammalian Brain (aka the Limbic System), located near the center of the brain and surrounds parts of the reptilian brain).
The limbic system is prominent among animals living in social groups, such as the apes. It also contains structures that are involved in emotions. Since the dynamics of social groups can be quite complex, the limbic system is essential in sorting out potential enemies, allies, and rivals.-Future of the Mind by Kaku.
500 Ma: Evolution of the reptilian brain.
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