Brain Structure and Function: Cerebrum, Cerebellum, Brain Stem

Spinal Bulb

The spinal bulb is the extension of the medulla. It contains gray matter surrounded by white matter. Ascending neural pathways pass through the spinal bulb. They come from the medulla and provide information to the brain. The right side of the brain receives information from the left side of the body, and the right side receives information from the left. The movement of the right part of the body is controlled by the left side of the brain (and vice versa). It regulates several body functions, such as heartbeat, blood pressure, and breathing.

Brain Stem

The brain stem is located between the spinal bulb and the brain, below the thalamus, and covers several areas of the brain. It regulates sleep, visual and auditory reflexes, and blood pressure. A part of the brain stem is the hypothalamus, which is connected to and controls the pituitary gland. This is an endocrine gland that secretes regulatory hormones to the rest of the organs.

Cerebellum

Located in the back of the brain, the cerebellum is made up of gray matter on the outside and white matter on the inside. It looks like a tree with branches (the "tree of life"). The cerebellum is the organ in charge of receiving information for balance and information that the inner ear sends. It coordinates motor impulses sent by the brain, which is fundamental for activities that use several muscles.

The Cerebrum

This is the largest part of the brain. It weighs 1200g and is made up of white matter on the inside and gray matter on the outside, which forms the cerebral cortex. It takes up a much larger area in humans than in other living beings and has many ridges. There are two types:

• Intergyrals: Numerous and shallow
• Fissures: Few and deep

One of the fissures divides the cerebrum into the hemispheres, right and left. They are connected by the corpus callosum. The left hemisphere is responsible for logic and analytical thinking, while the right is responsible for intuition and creativity. The remaining fissures are called lobes, and each one has a different function. They are located after the bone in the skull.

Brain Functions

• It processes received information and produces responses and signals for the effector organs.
• It controls higher nerve functions like memory, reasoning, intelligence, consciousness, and will.
• It coordinates and controls the functions of every part of the nervous system.