Below are few important points from the Book Super Brain By Deepak and Tanzi.
=> Astounding is the brain's ability to make new connections that a fetus on the verge of being born is forming 250,000 new brain cells per minute,leading to millions of new synaptic connections per minute.
Synapse definition: In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another cell (neural or otherwise).
=> The dynamics of the brain go in and out of balance but always favor overall balance,known as homeostasis.
=> Nerve cells(Neurons) are true wonders of nature in their ability to create our sense of reality.Neurons connect to each other to form vast and intricate neural networks. Your brain contains over 100 billion neurons and up to a quadrillion connections,called synapses.
Neurons project worm like threads called axons an dendrites which deliver both chemical and electrical signals across the gap between synapses. A neuron contains many dentrites to receive information from other nerve cells. But it has only one axon,which can extend out to over a meter(roughly 39 inches) in length.
An adult human brain contains well over 100,000 miles of axons and countless dentrites enough to wrap around the earth over four times.
Axon: An axon also known as a nerve fibre; is a long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses away from the neuron's cell body. The function of the axon is to transmit information to different neurons, muscles and glands.
Dendrites :Dendrites are the branched projections of a neuron that act to conduct the electrochemical stimulation(input) received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project. Electrical stimulation is transmitted onto dendrites by upstream neurons (usually their axons) via synapses which are located at various points throughout the dendritic tree. Dendrites play a critical role in integrating these synaptic inputs and in determining the extent to which action potentials are produced by the neuron.
=> Einsten a master of applying such amazing adaptability to physics saw himself as a failure as a husband and father. He divorced his first wife,Mileva in 1919 after living apart for 5 years. A daughter born out of wedlock in 1902 has disappeared from the pages of history.One of his two sons was schizophrenic and died in a mental asylum;the other,who suffered as a child when his parents seperated was alinated from his father for 2 decades. These sitations caused Einsten much pain.
=> Imagine a beautiful sunset in your mind's eye.No photons of light hit your retina,as they would if your were gazing at an sunset.No illumination lights up your visual cortex,which is submerged in the same blackness as the rest of the brain.Yet microvolts of electricity pumping ions back and forth along your neurons magically produce full of light,not to mention beauty and a cascade of associations with every other sunset you have ever seen.
ION: An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving the atom a net positive or negative electrical charge.
Glycine: Glycine is the smallest of the 20 amino acids commonly found in proteins. Proteins are large biological molecules consisting of one or more chains of amino acids. In short Glycine acts like a neuro-transmitter.
The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen, though other elements are found in the side-chains of certain amino acids.
Neurotransmitters : Neurotransmitters are endogenous chemicals that transmit signals from a neuron to a target cell across a synapse.
Receptors: Cell surface receptors (membrane receptors, transmembrane receptors) are specialized integral membrane proteins that take part in communication between the cell and the outside world. Extracellular signaling molecules (usually hormones, neurotransmitters, cytokines, growth factors or cell recognition molecules) attach to the receptor, triggering changes in the function of the cell.
Glutamate: Glutamate receptors are synaptic receptors located primarily on the membranes of neuronal cells.
=> In the triune(three part) model of the brain,the oldest part is the reptilian brain, or brain stem, designed for survival. It houses vital control centers for breathing, swallowing and heart-beat among other things. It also prompts hunger, sex and the fight or flight response.
The limbic system was next to evolve.It houses the emotional brain and short-term memory. Emotions based on fear and desire evolved to serve the instinctive drives of the reptilian brain.
The most recent developmentis the neocortex, the region for intellect, decision making, and higher reasoning.As our reptilian and limbic brains drive us to do what we need for survival, the neocortex represents the intelligence to achieve our ends while also placing restraints on our emotions and instinctive impulses. Most important for the super brain, the neocortex is the center for self-awareness, free will, and choice making the user and potentially the master of the brain.
=> Tucked under the cerebral cortex is the limbic system. It houses our emotions,feelings of pleasure associated with eating and sex,and our short-team memory.Located here are two individual areas,the thalamus and hypothalamus,as well as the amygdala and hippocampus,which control short-term memory.
Neocortex: The neocortex is a part of the brain of mammals. It is the outer layer of the cerebral hemispheres, and made up of six layers, labelled I to VI (with VI being the innermost and I being the outermost). The neocortex is part of the cerebral cortex (along with the archicortex and paleocortex, which are cortical parts of the limbic system).
Prefrontal cortex : The prefrontal cortex (PFC) is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behavior, personality expression, decision making, and moderating social behavior.The basic activity of this brain region is considered to be orchestration of thoughts and actions in accordance with internal goals.
The amygdala determines what memories are stored based on the emotional response that an experience invokes.The hippocampus is responsible for short-term memories and sends them to appopriate parts of the cerebral cortex for long-term shortage.This region is particularly affected in Alzheimer's disease.The limbic system is tightly connected with the olfactory lobe,which processes smell.This is why a certain scent can trigger such strong memories.
=> 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 behaviour and social integration.
The cerebral cortex is the most recently evolved part of the brain,consisting of a roughly 3-square-foot sheet of neural tissue spread out in six layers toward the outer surface of the brain.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.
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 temporaral 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 sesnsory information is processed along with spatial orientation, which lets you know where you are. Finally, in front of parietal lobes are the frontal lobes. The frontal lobes regulnate motor control and movement but also mediate our behaviour in society.
If the frontal cortex is damaged or, for example, contains a tumor, one might become pathologically uninhibited and turn into an extreme exhibiotionist or even a sexual molester.
The right and left hemispheres of celebral 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 corpus callosum is the lymbic system, which contains the thalamus and hypothalamus. The thalamus is involved in sensory perception and regulates movement. The hypothalamus regulates hormones, the pitutary gland, body temperature, the adrenal glands, and many other activities.
The two other major sections of brain are celebrallum, toward the rear of the brain, which controls coordination of movement, balance, posture; and the brain sytem (medulla oblongata and pons), which is the oldest part of the brain. It connects the brain to 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 immune system-are concentrated in specific regions of the celebral 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 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 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.
Pons: The pons is a structure located on the brain stem, contains nuclei that relay signals from the forebrain to the cerebellum, along with nuclei that deal primarily with sleep, respiration, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expressions, facial sensation, and posture.
=> 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 altrusistic behavior.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 observed 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.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 regions of the gyrus are larger in females than in males and are generally smaller in schizophrenic patients,which are often tragically isolated in their emotions and delusional about what other people are feeling.
=> 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,opiods and prolactin - regulate empathic responsiveness.
Oxytocin facilities 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 harmone" should not be taken literally.Love,being a complex behavior,is sensitive to many responses throughout the brain and 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.
=> Richard Dawkins,the british ethnologist and science writer who presents himself as a professional atheist,wrote a book for young people,The magic of reality,which addresses the whole issue of what is real.He informs the reader that if we want to know what's real,we use our five senses,and whe things are too big and far away (distant galaxies) or too small(e.g brain cells and bacteria) we augument our senses with devices like telescopes and microscopes.One anticipates that Dawkins will add a caveat that our five senses arent always realiable, as when our eyes tell us that the sun raises in the sky in the morning and sets at twilight,but he offers no such caveat.
=> We cannot fully explore the brain without addressing its deepest mystery. You are immersed in it every second of your life. Imagine that you are on vacation gazing at the Grand Canyon. Photons of sunlight glancing off the cliffs make contact with your retina and stream into your bain. There the visual cortex is activated through chemical and electrical activity, which comes down to electrons bumping into other electrons. But you aren't aware of this stormy, minuscule process. Instead, you see vibrant color and form;the awe-inspiring chasm appears before you, and you hear the whistling wind rush out of the canyon and feel the hot desert sun on your skin.
Something almost indescribable is happening here, because not a single quality of this experience is present in your brain. The Grand Canyon glows a brilliant red, but no matter how hard you search, you won't find a spot of red in your neurons. The same holds true for the other four senses. Feeling the wind in your face, you won't find a breeze in your brain, and its temperature of 98.6 degrees Farenheit won't change, whether you are in the Sahara or in Arctic. Electrons bump into electrons,that's all. Since electrons don't see, touch, hear, taste, and smell, your brain doesn't either.
=> Once when Deepak was giving a talk on the subject of higher consciousness, a skeptical questioner stood up in the audience. "I'm a scientist," he introduced himself, "and this is all smoke and mirrors. Where is God? You can't produce any evidence that he exists. Enlightenment is probably just self-delusion. You have no proof that supernatural things are real." Without passing to consider, Deepak replied, "You have no proof that natural things are real." Which is true. Mountains, trees and clouds look real enough, but without having the slightest idea how the five senses arose from electrons bumping into electrons, there is no proof that the physical world matches our mental representation of it.
=> In Jan 2010 Ray Tallis,who is described as a polymath,atheist and physician,mounted a pointed challenge to "the brain comes first" position.His article in the journal New Scientist was titled "Why You Won't Find Consciousness in the Brain". As a "neuroskeptic," Tallis attacks the most basic evidence that makes scientists believe that the brain creates Consciousness; those by-now-familiar fMRI scans that show regions of the brain lighting up in correlation with mental activity.At this point the reader already knows a good deal about them.Tallis repeats some of the points we have been making.
One of the first things a scientist is taught is that a correlation isnt a cause.Radios light up when music plays,but they dont create music.Likewise,one could argue that brain activity doesn't create thoughts,even though we now can see which areas are lighting up.
Neural networks map out and mediate electrical activity.They aren't actually thinking.
Electrical activity isn't the same as having an experience,which is what happens in Consciousness.
=> Asking the brain to "store" memory is impossible,Tallis contends.Chemical and electrical reactions happen only in the present.A synapse fires now,with nothing left over from the previous minute,much less the distant past.After the firing is over,the chemical signals that cross the synapse reset to their default position.The brain can strengthen certain synapses while weakening others through a process called long-term potentation.This is how certain memories become hardwired,while others do not.The question is whether the brain is capable of remembering what it did in the past,or is it actually consciousness that does this.Salt can disssolve only at the moment when you stir it into a glass of water.It cannot store a memory of dissolving in water in 1989.
Tallis notes that there are even more basic issues,such as the self - no brain location has been found for I,the person who is having an experience.You simply know that you exist.Nothing lights up in your brain;no calories are expended to keep your sense of self going.For all intents and purposes,if the self had to be proven scientifically,a skeptic could examine brain scans and prove that there is no I,except that obviously there is,brain scans or not.I is actually operating the whole brain. It is creating pictures of the world without jumping into the picture,just as a painter creates paintings without jumping into them.To say that brain creates the self is like saying that paintings create the painters.It does hold up.
Then there is the initiation of action.If the brain is a biological machine,as materialists agree(a famously phrase from an expert in artifical intellegence dubs the brain "a computer made of meat"),how does the machine come up with new,unexpected choices? The most powerful computer in the world doesnot say "I want a day off" or "Let's talk about something else." It has no choice but to follow its programming.
Source:
Super Brain By Rudolph E. Tanzi and Deepak Chopra. All Definitions From Wikipedia
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