The Brain

Sorry I haven’t posted much lately. I had some technical difficulties with my site and had to get some help figuring it out. Anyway, it’s time to go onto the brain! This is the really cool part.

The brain is a MIND BLOWING (yes, pun intended) organ that is much more complex than any supercomputer in existence on this planet and ever will! I love how David Balog describes it in his book, “Understanding the Brain”:

“The brain has been called the most complex structure in the known universe. This three-pound pinkish-gray organ controls intelligence, interprets the senses, initiates body movement, and mediates behavior. Lying in its bony shell and washed by protective fluid, the brain is the source of all the qualities that defines our humanity.  The human brain represents the crown jewel of the human body, if not of all life.” (1)

The brain weighs about three pounds when you become an adult. Every time you gain or lose three pounds remember that!

Remember when we talked about the decade of the brain? Through research, we found out so much exciting information about the brain structure, function, and how to help people who have disorders of the brain.

Brain Anatomy

There are several ways we divide up the brain in order to understand it’s structure. I’m going to talk about the lobes. But first, I want to give some really basic anatomy.

The top of the brain that you can see, is the cerebrum. This is called the FOREBRAIN. The forebrain helps with thinking, emotions, memory, and senses.

The brain is basically divided into two halves (right and left) and the corpus callosum splits it down the middle from front to back. Before we talk about the inside of the brain, let’s talk about the outside of the brain. On the outside of the brain, the cerebrum has many folds and each one is unique, like snowflakes. The groves made  by the folds are called sulci. The ridges are called gyrus. These sulci and gyrus are only about 3 to 5 mm in thickness. The part you see in pictures is called gray matter and this gray matter is covering white matter. The cerebrum is made up of over 50 billion (Yes, I really said 50 billion) neurons which interact chemically and electrically with one another.

The cerebrum wraps around some very important structures in the brain. These include the pituitary gland, the thalamus, hypothalamus. Each of these structures have very specific functions which work together with the rest of the brain to perform extremely important jobs.

The Lobes of the Cerebrum

Again, the cerebrum is essentially divided up into several lobes. These lobes are what we call the FOREBRAIN. These are:

• The frontal lobe
• The temporal lobe
• The parietal lobe
• The occipital lobe

The frontal lobe is the largest lobe of the brain, and responsible for language and what is called executive functioning.  Executive functioning is a bunch of skills that we don’t really think about but control our behaviors. We covered these in a previous post. For a review, click here. These are things like organization, planning, attention, controlling impulses, working memory (holding temporary memories), the ability to reason, and being flexible when we have to go from one plan to another. People who have ADHD have difficulty with these tasks. They may be impulsive and interrupt others while they are talking, or they may not be able to start a school project because they feel overwhelmed with all the tasks it requires and cannot plan it out step by step.

The temporal lobe is the second largest lobe in the brain. It is responsible for processing what you hear and allows your brain to pull up memories so you can decode the auditory information.  For example, if you hear a whistle next to a railroad track, your temporal lobe helps you to remember that it’s a train whistle even if you don’t see the train yet. Some people have temporal lobe seizures which cause them to perseverate on certain words.

The parietal lobe takes the input from your sensory system and helps you make sense of it. For example, if you put your finger on a hot stove, your parietal lobe helps you to know to take your finger off that surface.

The occipital lobe is located in the back of your skull and it is responsible for interpreting what you see out of your eyes.  It helps decode information about the color, shape, and how it moves. If you see your best friend coming toward you, your occipital lobe help you remember their face, hair color, and memories of things you have experienced with that person.

These are very simplistic explanations.  Remember that these lobes don’t work without other parts of the brain. As we go along talking about specific mental illnesses, there will be more information about how the brain works together.

The Midbrain

The midbrain is inside the cerebrum (the large top part of brain). This is called the MIDBRAIN. It works on motor movements particularly with the eyes and processing the information you see. This is a good example of how your brain works together because we already discussed that the occipital lobe has similar functions. Your occipital lobe and midbrain work together to help you to decode what you see.

The Hindbrain

The HINDBRAIN includes the pons, the medulla and the cerebellum (not to be confused with the cerebrum. Two different words). The medulla helps with your heartbeat, breathing, digestion, and some reflexes such as sneezing and coughing. You don’t control these things so this part of the brain helps your involuntary function. The cerebellum helps you keep your balance when you’re walking and other movements related to balance.  It also helps to remember how to do things that you know including riding a bicycle. You already learned and now you just get on and ride because of your cerebellum.

If you want more information about the brain, this is a really great video by Kahn Academy about the brain: Click here.

Okay! We’re pretty much done with basic neuroanatomy! HURRAY! Thanks for sticking in there with me. Next we will start talking about specific mental illnesses…. Stay tuned!

References:

Balog, D. (2017). Understanding the Brain. Fetal Alcohol Spectrum Disorders.

Kahn Academy. (2019). Brain: Parts & functions (Fore, mid & hind). https://www.youtube.com/watch?v=DtkRGbTp1s8

Parker, S (2013). The Human Body Book. DK Publishing: London.