5. The Human Brain


THE HUMAN BRAIN - More Powerful than 200 Million Desktop Computers


The average human brain weighs about 1.5kg (3lb) and looks like a big, grey, wrinkly sponge about the size of your two fists put together. It is comprised of 78% water. If the water was removed, 60% of dried brain weight is fat.  


While we are awake, our brain generates up to 25 watts of power:  enough to illuminate a light bulb. Our brain has the thinking capacity of more than 200 million iPads. Our brain's hardware has amazing potential. The software, however, is often sadly lacking.


The brain is basically the headquarters of the human body. Electrical currents pass throughout the entire brain to perform an incredible number of tasks. It controls body temperature, blood pressure, heart rate and breathing. It handles physical movement such as walking, standing or sitting. It accepts a flood of information about the world around us from our various senses - seeing, hearing, smelling, touch and taste. It thinks, dreams, reasons and experiences emotions. All this, even when we are sleeping, is coordinated, controlled and regulated by our brain. ​


Brain Chemicals are called neurotransmitters and help signals cross from one neuron, or nerve cell, to the other. Neurotransmitters play a key role in the function of the central nervous system and can either prompt or suppress the further signaling of nearby neurons. Many events can trigger neurotransmitters, but rather than being in the passenger seat, there are many ways we can intentionally cause them to flow. Being in a positive state has significant impact on our motivation, productivity and well-being. Endorphins, Dopamine, Serotonin and Oxytocin are the quartet of neurotransmitters responsible for our happiness.


Endorphins​ are our own private narcotic - our feel good chemical and natural pain killer. Endorphins are responsible for blocking physical pain and for our feelings of pleasure. ​Endorphins are released during exercise. You may have heard the term 'runner's high'. This is endorphins at work​ and the reason that exercising is so good for our mental health.


Dopamine is a​nother​ feel good chemical. Dopamine is the motivation molecule in charge of our pleasure​ and ​reward system. Dopamine motivates us to take action toward goals, desires and needs​;​ and gives a surge of reinforcing pleasure when ​we ​achieve​ them.


Serotonin is our 'happy hormone', the brain chemical responsible for regulating ​our moods. It is ​​the leadership chemical​ which is​ responsible for feelings of significance, importance, pride and status. Serotonin is also responsible for social behavior, appetite and digestion, immune function, sleep, memory, and sexual function. Therefore, it has a wide variety of functions that keeps humans happy and on track​. ​80-90% of serotonin is manufactured and lives in ​our​ gastrointestinal tract​​.​


Oxytocin ​is our​ love chemical. Oxytocin creates intimacy, trust, and builds healthy relationships which make us feel satisfied. Oxytocin is the best chemical of all, giving us all the warm and fuzzies.  It's the bond between mother and child: the​​ intense feeling of safety and knowing someone has got your back​, of m​orality and ​t​rust promoting connectedness and calmness. The cultivation of oxytocin​​ is essential for creating strong bonds and improved social interactions.


We can produce endorphins ​and​ ​d​opamine on our own​ - whereas serotonin ​and o​xytocin are triggered relationally and attempt to manage ​​Endorphin​s​ & Dopamine. Serotonin and Oxytocin are ​the chemicals t​hat make our society great.


Cortisol is our primary stress hormone. We release it when we are under any sort of pressure. It is our evolutionary-based fight or flight response. The amount of cortisol in our body is driven by the amount of stress ​we​ are experiencing. In addition, caffeine consumption, our eating patterns, how physically active we are, and our sleep patterns all affect how much cortisol is released into our system. Cortisol binds to receptors on ​our​ fat cells, liver and pancreas, which makes energy sources available for muscles to use​ to fight or flee​. It also temporarily inhibits other ​body ​systems, including digestion, growth, reproduction and the immune system.


To better understand the role of brain chemicals, it is important to note that we are ​​predominantly visual ​and social animals​. We  respond to things we see and we belong in a 'tribe'​. This is how the human race has survived so far.


"When you see how exercise, diet, hydration and relationships interact to effect our brain chemistry, the concept of Holistic Mental Health starts to become clear".




Food For Thought


What new knowledge did you gain from this lesson?


Now that you know this, how could it be applied?