The Cerebral The Cerebral CortexCortex

Chapter 2, Lecture 5Chapter 2, Lecture 5

“…the mind is what the brain does.”- David Myers

The Cerebral CortexThe intricate fabric of interconnected neural cells

that covers the cerebral hemispheres. It is the body’s ultimate control and information processing center.

Structure of the CortexEach brain hemisphere

is divided into four lobes that are separated by

prominent fissures. These lobes are the

frontal lobe (forehead), parietal

lobe (top to rear head), occipital lobe

(back head) and temporal lobe (side of

head).Watch this video clip about mapping

brain functions in the cerebral cortex.

Functions of the CortexThe Motor Cortex is the area at the rear of the frontal lobes that control voluntary movements. The Sensory Cortex (parietal cortex) receives

information from skin surface and sense organs.

The Sensory HomunculusWhat we would look like if our bodies were inproportion with the amount of cortical space devotedto each body part:

The Frontal Cortex

Phineas Gage reconsideredMyers: Psychology, Ninth EditionCopyright © 2010 by Worth Publishers

Consider the famous case

study of Phineas Gage.

And now another similar case

study…

Visual Function

The functional MRI scan shows the visual cortex is active as the subject looks at faces.

Courtesy of V

.P. C

lark, K

. Keill, J. M

a. M

aisog, S. Courtney,

L.G

. Ungerleider, and

J.V. H

axby, National

Institute of Mental

Health

Auditory Function

The functional MRI scan shows the

auditory cortex is active in patients who

hallucinate.

More intelligent animals have increased “uncommitted” or association areas of the

cortex.

Association Areas

The brain is sculpted by our genes but also by our experiences.

Plasticity refers to the brain’s ability to modify itself after some types of injury or

illness.

The Brain’s Plasticity

The most dramatic examples of brain plasticity are seen in people following

hemispherectomies.

HomeworkRead p.75-81

“As we move up the ladder of animal life, thecerebral cortex expands, tight genetic controlsrelax, and the organism’s adaptability increases.”

- David Myers