The Parts: The neurons and the glia
There are four types of glial cells. These cells guide developing neurons in the early stages of brain growth, protect and nourish neurons and clean up dying neurons.
Neurons account for only one tenth of the cells in the brain, but they, along with the neurotransmitters (brain chemicals), are responsible for recording how to function (moving, breathing, seeing) and how to act, think and feel.
The Process of learning
All information enters your brain by the senses: hearing, taste, touch, smell, and sight. The specific signals from the senses, such as sound and light waves, activate certain neurons, or nerve cells. Signals from stimuli in the environment come into the cell by its many arms, the dendrites, travels through the axon and then connects with a myriad of other dendrites. The signal is passed from cell to cell by chemicals known as neurotransmitters. The signal continues through many other cells. We cannot comprehend the speed at which the electrical signals pass nor the number of neurons they pass through.
The more a particular signal travels through the neuron circuit, the more efficient it becomes. Glial cells begin to wrap around it, supplying it with a fatty material to insulate it; this is known as myelin sheath. Because of this process, difficult things become easier to do. Also, you can recall things much more easily. Some neurons are so well insulated and efficient, that thoughts and information are quickly recalled and actions automatically produced. Figuratively speaking, the recording of it has gained greater quality and can be played back better.
Signals, of course, come in all the time. Your brain takes in all this information, and, if there is a match for a signal, it travels along its beaten path, and manifests itself as a thought, word, or action. Completely new signals must forge a new path. If the signal is not immediately repeated or attended to, the path soon fades and it is as if it was never there. A new piece of recorded information can last for several days, but it takes work to keep it there. This is why you can study something, think you know it, and then….it is gone. Additionally, this is why you can change your behavior, only to go back to the old ways.
For a piece of information (including actions) to be permanent, it must be repeated a lot. Eventually information and skills are well-insulated with a strong synaptic connection; when this happens, we say that it is a part of long term memory. Poorly insulated neurons are subject to decay due to non-use. Conversely, used ones become more and more efficient, making it a dominating and permanent thought or action. In fact, sometimes these dominating thoughts and patterns of behavior make it difficult for new incoming information to receive proper attention. These dominating actions (which would include words we say) create the personality we have.
In addition to understanding how our actions, thoughts, and words are produced, understanding this process helps us understand how the environment continues to influence us. This process, with the interconnectedness of our neurons, can make one thought lead to another. In addition, an action or thought can be triggered by varying stimuli. This is because neurons are are interconnected-via the dendrites- with countless other neurons. As a result, the smell of something can trigger memories and you can develop “environmentally based” temptations, such as eating chips while watching movies. This is why doing something physical to remember information is effective. In fact, neuron connections that control movement (learning to ride bike, for example) are designed for easy and permanent insulation.
The Process of behavior and thought
Incoming stimuli from sensory receptors is changed to an electrical signal and is brought to the thalamus (which is part of the limbic system). There, it begins the multiple chains of signals to the other parts of the brain. The signals are then processed in the amygdala (with the aid of the hippocampus and hypothalamus), followed by the pre-frontal cortex.
The amygdala inspects the signals for safety threats or possibilities of pleasure. If circuits for a significant threat are stimulated, the signal will follow a direct path for action. For example, the adrenal system releases adrenaline and stress hormones. All functions that are not critical are turned off. Blood pressure increases in order to prepare the brain and muscles for work. The pupils dilate, the liver breaks down glycogen to prevent an energy crisis. These reactions happen because the body has a response system to protect itself from danger. The body is continually analyzing signals with the norms the brain has established. In addition to threats, the mind has been created to ensure reproduction of mankind. Both of these situations trigger responses that are nearly (if not completely) automatic; a person has little power to overcome intense feelings of fear and physical attraction. These, and other strong emotional reactions, are wired in the brain stem and limbic system.
The brain stem and limbic functions store non-declarative memory; in other words, the strong neuron connections of these areas cause us to act little to no thinking on our part.
Let’s look at the importance of the ability to think, which is the ability to use the prefrontal cortex’s working memory . To do so, let me share with you the story of Phineas Gage.
This is a tragic, but true, story that took place in 1848. An industrious and well-respected man, Phineas worked as a supervisor for the railroad. Unfortunately, his good work and reputation ended abruptly when he was struck in the skull while working. A metal rod went through his brain and removed his left temporal lobe, severing his brain stem from his frontal cortex. Phineas, amazingly enough, regained health; never, however, did he gain the ability to control his emotions or make responsible decisions. As normal, signals came into his mind as and triggered emotional responses. Unfortunatley, because the signals could not reach his prefrontal cortex to be analyzed with stored information and skills he had in regards to self-control, social behavior, or delaying needs, Phineas was doomed to act out the behaviors that his brain signaled his body to perform: mad, happy, sad and fearful behaviors.
Understanding the functions of emotions helps us realize the important role emotions play in our lives. They are not bad influences. Emotions are to our behavior as reflexes are to our physical movement. When the brain senses that something is too hot, it will immediately signal the arm or leg to move away. Likewise, when the brain senses that something is rewarding or harmful, the brain signals emotions that help us go for, withdraw from, modify, or maintain a particular action. Pain brings the desire to fix something. Happiness brings the desire to keep doing something.
The process that produces stress
One critical but misunderstood response is stress. Stress, the bodies reaction to a challenge or demand, releases the hormone cortisol. Cortisol prompts and aids us in taking action by increasing our heart rate and sugar levels. This is good for circumstances when you need peak performance: a presentation, responding in an emergency, taking a test. Nonetheless, it can be a damaging response. Just like other neural circuits, the neurons that trigger this response can become well-insulated. Hence, the slightest stimulus can activate them.
Why it matters
Stress effects the learning abilities and behaviors of the students. Educators must be aware of the emotional environment in and outside of the classroom. More importantly, educators must be able to maintain a healthy emotional environment and teach students how to handle difficulties.