Healthy Nervous System
1 AnswerDr. Mike Clark, DPT, Fitness, answeredThe nervous system is an important facet of an exercise plan. In the beginning of an exercise plan, early adaptations and strength gains come from the nervous system. Within two weeks of resistance training, you will become stronger. Each muscle is made up of numerous muscle fibers. Each muscle fiber has nerves attached to it. When we are sedentary, the body will call on as few muscle fibers as necessary to work, leaving other muscle fibers "dormant." When we begin to move more, do resistance training, or participate in challenging physical activity, the muscles are called upon to do more work. When this happens, more nerves are asked to recruit more muscle fibers, which are "awakened" and assist with the activity, thus increasing your strength.
1 AnswerHealthwise answered
The nervous system includes the brain, the spinal cord and all the nerves in the body. Nerves carry information through the spinal cord to the brain about what is happening inside and outside of the body, and the brain processes the information and sends messages back through the nerves that control how muscles and other organs respond. The nervous system is divided into the brain and the spinal cord (which are together known as the central nervous system) and the nerve cells that lead away from the brain and the spinal cord to the rest of the body (peripheral nervous system). The nervous system controls:
- Sight, hearing, taste, smell and feeling (sensation).
- Voluntary and involuntary motor functions, such as movement, balance and coordination. It also regulates the actions of most of the other body systems, such as blood flow and blood pressure.
- The ability to think. The nervous system allows a person to be conscious, to have thoughts and memories and to use language.
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1 AnswerDebra Fulghum Bruce PhD, Healthcare, answeredPhenylethylamine is a brain chemical that is linked to energy, mood and attention. It is similar in some ways to amphetamines and may play a key role in what is known as the “runner's high." A National Health and Nutrition Examination Survey found that physically active people were half as likely to be depressed a decade later as those who were inactive.
1 AnswerMichele Borba, Psychology, answeredFirstborn sons have higher IQs than their younger brothers because of how they are raised. It is NOT genetics!
In a study lead by a psychologist, Petter Kristensen, researchers took a decade to meticulously analyze IQ scores of 250,000 men. All the men took the IQ test when they were 18 or 19 years old and were required to do so as draftees entering the Norwegian army. Though no women were involved in the study, the researchers contend that the same results would happen for women. (I know, I know. Another study that assumes that women are going to turn out the same as men….but….)
Results found that the oldest child is smarter than next oldest sibling by an average of 2.3 points, who is turn beat the third-born brother by 1.1 points. But here is the fascinating detail: If the eldest child dies, the second sibling becomes the smartest one.
That means it’s not just birth order or the gene pool that’s boosting those IQ points. The dynamics in the family and how the first born kid is treated in that home environment plays a key role.
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With the help of brain imaging, scientists can see which parts of the brain light up. They also know that our consciousness can be altered with chemicals or surgeries.
But they remain uncertain about the precise stage at which a firing neuron becomes a conscious thought.
Scientists continue seeking a better understanding of the relationship between unconscious and conscious experiences. There are some things, like breathing and maintaining a regular heart beat that go on without conscious thought. Researchers are trying to learn how these unconscious actions are wired differently from the actions that require conscious thought.
Even though we like to think we make our own decisions, there is even some research that indicates we might not even do that. One study found that by using brain scanners, researchers were able to predict how a person would act a full seven seconds before the person knew a decision had been made. However, researchers acknowledged that the study was best suited to a simple test that involved pushing a button, as opposed to a more complicated decision such as accepting a job.
Like the electrical system in your house, if there?s a breakdown in your internal electrical system, things stop working. If you experience an extreme overload, like being struck for lightning for instance, your system could get completely fried and shut down.
But there are smaller problems when your internal electrical system goes haywire. These include what happens when a SA node misfires causes a heart palpitation (an extra heartbeat), or when a lack of blood flow to the heart upsets the SA node and causes other parts of the heart to send out impulses.
If the heart is being told constantly to contract, it never gets enough blood to the rest of the body. That leads to oxygen deprivation and may result in a heart attack or stroke.
The starting part is easy: Any cells in your body that are not actively sending messages are slightly negatively charged.
The natural resting state of your cells is negativity. This state is related to an ever so slight imbalance between potassium and sodium ions, both inside and outside the cell. The imbalance then sets the stage for your electrical capacity.
Your cell membranes then perform a trick that is sometimes called the sodium-potassium gate. It is a complex mechanism, but a simple way to explain these gates and how they generate electrical charges, goes something like this: When they are at rest, your cells have more potassium ions inside them than sodium ions, and there are more sodium ions on the outside the cell. Potassium ions are negative, which explains why the inside of a cell has a slightly negative charge. Sodium ions are positive, which explains why the area immediately outside the cell membrane is positive. But because the cells are at rest, there is not a strong enough charge difference to generate electricity.
The body opens the sodium-potassium gate when it needs to send a message from one point to another. When the gate opens, potassium and sodium move freely into and out of the cell. The negatively charged potassium ions exit the cell, attracted to positivity outside the membrane, and the positively charged sodium ions enter into it, heading toward the negative charge.
The result of these movements is a switch in the concentrations of the two types of ions, as well as a rapid switch in the charge. It is somewhat like switching between a 1 and a 0. The flip between positive and negative results in generating an electrical impulse.
This impulse then triggers the gate on the next cell to open, creating another charge, and so on. This is how an electrical impulse from a nerve in your jammed finger travels to the area of your brain that senses pain.
We need the electricity in our body to survive. Electrical signals are super fast. They allow a nearly instantaneous ability to control messages. If our bodies had to rely on the movement of chemicals to direct our hearts to speed up when something was chasing us, the human race probably would have died out a long, long time ago.
The signals that tell our hearts to speed up when danger lurks come from a mass of cells in our hearts known as the sinoatrial node, or SA node. The SA node, in the right atrium, controls the rhythm of our heartbeat and directs the movement of blood from the heart to everywhere else in our body. The SA node is our body's natural pacemaker, using electrical signals to set the pace.
3 AnswersMehmet Oz, MD, Cardiology, answeredIf you check the US Army Survival Manual's basic principal of cold weather survival it says to always keep your head covered because you can lose 40-45% of your body heat from an unprotected head. Tell that to the guy standing outside with no pants on. Truth is you lose no more heat from your head than any other portion of your body. Any part of your body exposed to the cold will drop core body temperature. When emergency medical technicians treat for hypothermia, they apply heat to the chest, neck, armpits and groin. The head? Not so much.