Undoubtedly, the brain is the most complex part of the human body. Weighing in at three pounds, this organ is the base of man’s intelligence, the initiator of all motor neuron movements, and the seat of man’s emotional stability.The Crown Jewel of the human body lies in a bony shell and is washed by a protective fluid. Although the human brain shares the same structure as other mammalianbrains it is considered larger in proportion to body size.

Structure of the Brain

There are 3 major parts of the brain: cerebrum (Latin for brain), cerebellum (little brain), and brainstem.

The cerebrum is the largest part of the human brain. It is divided into two, the right and the left hemisphere, which are connected by a bundle of nerve fibers. The cerebral cortex is the outermost layer of the cerebrum and has four lobes - the parietal lobe, frontal lobe, occipital lobe and temporal lobe.

As is the case with all vertebrates, the human brain develops from 3 sections known as the midbrain, the hindbrain and the forebrain. Each section contains fluid filled cavities known as ventricles.The midbrain becomes part of the brainstem, the forebrain becomes the cerebrum and other underlying structures and the hindbrain develops into regions of the brainstem and cerebrum.

Additionally, the limbic system (or the emotional brain) is buried within the cerebrum.

Right Brain vs. Left Brain

The two hemispheres of the brain are connected by the corpus callosum, which is composed of a bundle of fibers. The two hemispheres are somewhat symmetrical. The right brain controls the muscles on the left side and vice versa. It is believed that one hemisphere is slightly dominant, and thus the association with right or left handedness

There are some key roles played by both regions of the brain. The left brain plays a huge part in language and speech, and is also linked to fact retrieval and mathematical calculation. The right side of the brain   plays a role in auditory and visual processing as well as spatial and artistic abilities.

Brain Structure and Function - 3D Animation:

Functions of Major Brain Parts

The functions of the brain parts according to structure of the brain are listed below:

The Cerebrum (Thought and Action)

The cerebrum/cortex is the largest part of the brain and is divided into four sections called lobes. The function of these lobes is listed below:

• Frontal lobe- Associated with planning of speech, reasoning, emotions, problem solving and movement.
• Occipital lobe- It’s associated with visual processing
• Parietal lobe- It’s associated with recognition, movement, orientation, perception of stimuli, speech and memory.
• Temporal lobe- It’s associated with memory, speech, and the perception and recognition of auditor stimuli

The cerebral cortex is wrinkled, which increases the brain surface and neurons within it, thus making the brain more efficient.

The Limbic Systemis buried within the cortex and has the following parts:

• Hypothalamus- It controls the pituitary gland, the autonomic nervous system and emotions. It is also involved in functions such as homeostasis, thirst and hunger.
• Thalamus- It has sensory and motor functions. All sensory information enters this structure before neurons dispatch the information to the overlying cortex
• Amygdala- Located in the temporal lobe, it’s  involved in memory, emotion and fear
• Hippocampus- Located in the mid part of the temporal lobe, this part of the brain is responsible for learning and memory, for converting short term memory to long permanent memory and for recalling spatial relationships in the world around us.       

The Cerebellum (Coordination)

Also known as the little brain, the cerebellum has two hemispheres with a highly folded surface. This part of the brain is associated with the coordination and regulation of posture movement and balance.

Brain Stem (Vital Body Functions)

This structure is responsible for vital functions such as breathing, heartbeat and blood pressure. Scientists regard this as the simplest part of the human brain on account of the fact that all animals’ entire brains resembleours.

The brain stem is made of the midbrain, pons(which is involved in motor control and sensory analysis)  and the medulla (also known as oblongata, it is the largest part of the brain stem and is responsible for maintaining vital body functions such as the heart rate and breathing).  

Brain Facts You Want to Know

After learning the structure of the brain, here are the fun facts:

• Weight – Your brain weighs some three pounds, which is half the weight of your skin.
• Gray matter-The brain’s gray matter is made up of neurons, which gather and transmit signals. There are about 100 Billion neurons in the brain. It takes up 40% of brain matter.
• White matter- The white matter is made up of dendrites and axons that create the network by which neurons send their signals. It takes up 60% of brain matter.
• Numbers- The brain is made up of 75% water. It has 60% fat thus making it the fattest organ in the body. It has at least some 100,000 miles of blood vessels in the brain. The brain generates between 10 -23 watts of energy whilst you are awake and this is sufficient to light up a bulb.