Your brain is your most powerful organ, yet weighs only about three pounds. It has a texture similar to firm jelly.
It has three main parts:
- The cerebrum fills up most of your skull. It is involved in remembering, problem solving, thinking, and feeling. It also controls movement.
- The cerebellum sits at the back of your head, under the cerebrum. It controls coordination and balance.
- The brain stem sits beneath your cerebrum in front of your cerebellum. It connects the brain to the spinal cord and controls automatic functions such as breathing, digestion, heart rate and blood pressure.
Your brain is nourished by one of your body’s richest networks of blood vessels.
With each heartbeat, arteries carry about 20 to 25 percent of your blood to your brain, where billions of cells use about 20 percent of the oxygen and fuel your blood carries.
When you are thinking hard, your brain may use up to 50 percent of the fuel and oxygen.
The whole vessel network includes veins and capillaries in addition to arteries.
Your brain’s wrinkled surface is a specialized outer layer of the cerebrum called the cortex. Scientists have “mapped” the cortex by identifying areas strongly linked to certain functions.
Specific regions of the cortex:
- Interpret sensations from your body, and sights, sounds andsmells from the outside world.
- Generate thoughts, solve problems and make plans.
- Form and store memories.
- Control voluntary movement.
Your brain is divided into right and left halves. Experts are not certain how the “left brain” and “right brain” may differ in function, except:
- The left half controls movement on the body’s right side.
- The right half controls the body’s left side.
- In most people, the language area is chiefly on the left.
The real work of your brain goes on in individual cells. An adult brain contains about 100 billion nerve cells, or neurons, with branches that connect at more than 100 trillion points. Scientists call this dense, branching network a “neuron forest.”
Signals traveling through the neuron forest form the basis of memories, thoughts, and feelings.
Neurons are the chief type of cell destroyed by Alzheimer’s disease.
Signals that form memories and thoughts move through an individual nerve cell as a tiny electrical charge.
Nerve cells connect to one another at synapses. When a charge reaches a synapse, it may trigger release of tiny bursts of chemicals called neurotransmitters. The neurotransmitters travel across the synapse, carrying signals to other cells. Scientists have identified dozens of neurotransmitters.
Alzheimer’s disease disrupts both the way electrical charges travel within cells and the activity of neurotransmitters.
100 billion nerve cells…100 trillion synapses…dozens of neurotransmitters…This “strength in numbers” provides your brain’s raw material. Over time, our experiences create patterns in signal type and strength. These patterns of activity explain how, at the cellular level, our brains code our thoughts, memories, skills and sense of who we are.
Quoted from Source: actionalz.org – inside_the_brain