The brain: three pounds of jelly that control your thinking, feelings, movement, breathing, digestion, circulation, and more. It’s made up of three major parts that are highly interconnected and dependent on each other. Each part has its own primary set of functions.
1. The Cerebrum
The cerebrum takes up 80 percent of your brain, and sits up front and center. It’s made up of four major lobes and is divided into two halves, the right and left hemisphere.
The right hemisphere controls motor functions on the left side of the body and vice versa. Areas of the cerebrum communicate to each other via nerve fibers called white matter. The largest white matter tract, or cable system, is called the corpus callosum, which connects the two hemispheres.
The main functions of the cerebrum include:
- Interpreting sensations such as vision, hearing, touch, and smell
- Controlling our feelings and emotions
- Thinking, problem solving, and adapting our behaviors
- Learning and remembering
- Understanding and using language to communicate
- Perceiving the space around us
- Body movement
The primary functions of each lobe in the cerebrum include:
- The frontal lobes, the biggest, are located up front. They’re the “executive” part of the brain, or our brain’s CEO. Higher order thinking goes on here, including reasoning, planning, organizing, and changing our behavior to fit the environment or situation. They also control movement, speaking and, to some extent, emotion.
- The parietal lobes, right behind the frontal lobes, are primarily responsible for recognizing and interpreting sensory information from the outside world, such as taste, temperature, smell, and touch. They help us to understand spatial relationships such as shape, size, and the orientation of objects in relation to our body. This area is also important for academic skills such as reading and math.
- The temporal lobes are right above the ears and help us process sound (including music). They are also important for learning and memory, as well as the understanding of language.
- The occipital lobes at the back of the brain help process what you see.
There is a fifth lobe located deep inside the cerebrum, right above the brainstem, that deserves special mention because of its important functions. It is called the Limbic lobe and is really a system of interconnected structures which include:
- The thalamus is the “central hub” of the brain. It receives outside information – all the senses except smell – and forwards it to other areas of the brain. It also helps manage motor and cognitive functions.
- The hypothalamus, just below the thalamus, helps regulate sleep, hunger, and body temperature by sending instructions to produce hormones, including adrenaline.
- The hippocampus is critical to learning and memory, especially for turning memories from short-term to long-term.
- The amygdala manages emotions that have to do with survival – especially fear – and memory. It also triggers sexual desire and response.
2. The Cerebellum
Tucked away under the cerebrum at the back of your head is the cerebellum. It accounts for about 11 percent of your brain, and is packed with neurons – brain cells with interconnecting branches that pass along nerve signals.
The functions of the cerebellum include:
- Coordinating movement and balance
- Fine tuning thoughts, emotions, touch, and other senses
The cerebellum helps “automate” movements so you can do things like type quickly and accurately or learn dance moves.
3. The Brain Stem
The brain stem runs from under the cerebrum to the spinal cord. It controls all the body’s automatic functions. Except for the nerve that controls smell, the brain stem connects to 11 other cranial nerves in the head.
The functions of the brain stem, the oldest part of the brain, are essential to maintaining life:
- Heart rate and blood pressure
- Body temperature
- Reticular activating system (RAS) that makes the brain alert (in conjunction with the thalamus, hypothalamus, and cerebellum)
The information presented in this site is intended for general information and educational purposes. It is not intended to replace the advice of your own physician. Contact your physician if you believe you have a health problem.