Phineas Gage · Phineas Gage: Phineas Gage was a railroad worker in the 19th century living in...

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Phineas Gage: Phineas Gage was a railroad worker in the 19th century living in Cavendish, Vermont. One of his jobs was to set off explosive charges in large rock in order to break them into smaller pieces. On one of these instances, the detonation occurred prior to his expectations, resulting in a 42 inch long, 1.2 inch wide, metal rod to be blown right up through his skull and out the top. The rod entered his skull below his left cheek bone and exited after passing through the anterior frontal lobe of his brain.

Poor Mr. Gage would never be the same person again!WHY???

Cerebrospinal Fluid (CSF) fills space between the meninges. This provides a protective “cushion” for the brain.

Skull

Dura mater

Arachnoid Layer

Pia Mater

Brain

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The cerebrum’s surface - the cerebral cortex - is convoluted into hundreds of folds made of gyri (singular gyrus) and sulci (singular sulcus).

The cerebral cortex is where all the higher brain functions take place.

Cerebral Cortex

The Corpus Callosum is the fibrous tract of white matter that connects the right and left cerebral hemispheres.

● Left side of the brain is responsible for the right side of the body and vice versa

The cerebrum is often divided into five lobes that are responsible for different brain functions.

frontal lobetemporal lobeparietal lobeoccipital lobelimbic lobe

Corpus callosum

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The cerebral cortex is a thin layer of cells about 1.5 to 4 mm thick.

The cortex provides the connections and pathways for the highest cognitive functions, such as language and abstract thinking.The cerebral cortex contains about 25 billion neurons, more than 62,000 miles of axons, and 300,000,000,000,000 synapses.

Cerebral Cortex

The thin layer of the cerebral cortex is dense with neurons.

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Parietal Lobe

Temporal Lobe

Frontal Lobe

Limbic Lobe

Occipital Lobe

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Gage’s personality, reasoning, and capacity to understand and follow social norms had been diminished or destroyed. He illustrated little to no interest in hobbies or other involvements that at one time he cared for greatly. ‘After the accident, Gage became a nasty, vulgar, irresponsible vagrant. His former employer, who regarded him as "the most efficient and capable foreman in their employ previous to his injury," refused to rehire him because he was so different.

- This encouraged the procedure called the pre-frontal lobotomy

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The limbic lobe is located deep in the brain, and makes up the limbic system.

Functions:

• regulates emotion and memory

The cerebellum is connected to the brainstem.

Called arbor vitae (tree of life)

Functions:

• “autopilot” for body movement and balance.

• a complex series of spaces and tunnels through the center of the brain

• secrete cerebrospinal fluid (CSF), which suspends and protects the brain in the skull.

• provide a route for “chemical messengers” that are widely distributed through the central nervous system.

Cerebrospinal fluid is a colorless liquid that bathes the brain and spine.

It is formed within the ventricles of the brain, and it circulates throughout the central nervous system.

Cerebrospinal fluid fills the ventricles and meninges, allowing the brain to “float” within the skull.

The Diencephalon contains the...

● Epithalamus, Thalamus, Hypothalamus, pineal gland, etc.

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Relays sensory information between brain reigons and controls autonomic functions of the peripheral nervous system.

Mid Brain

Responsible for… vision, hearing, motor control, sleep/wake, arousal (alertness), and temperature regulation.

Pons Postman Pons: Serves as a message man so the different parts of the brain can communicate with each-other. Mainly between the cerebrum and the cortex.

Medulla Oblongata

VERY IMPORTANT: Controls breathing, heart rate, digestion, and swallowing.