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last updated:

Feb 27, 2021

  

[Brain Image]    

PSY 340 Brain and Behavior

Class 11: Cerebral Cortex [Outline] 

   

Cerebral Cortex

[Cerebral Cortex]   [Gray & White Matter]      
• "gray matter" consists mostly of the bodies of neurons
• "white matter" consists mostly of axons from neurons

    

 Each of the two cerebral hemispheres communicates with the other via several bundles of axons. The largest is the corpus callosum (see diagram on the right and left below). A second, smaller connection is the anterior commissure (see diagram on the left below).
    [Commissures]

Organization of the Cerebral Cortex


[Layers of Cortex] [Columns of Cortex]

Laminae: Six Layers or laminae (singular = lamina)


Columns

[Lobes of the Brain]Central Sulcus: A sulcus (sulci, pl.) is a fissure, groove, or depression on the surface of the cortex. These sulci normally separate ridges or protrusions of cortical tissue called gyri (gyrus, singular).

The central sulcus separates the Frontal from the Parietal Lobe of the brain. Anterior to (in front of) the Central Sulcus lies the Precentral Gyrus. We have already seen this area under the label of the brain's "Motor Strip." Posterior to (in back of) the central sulcus lies the Postcentral Gyrus. We have already seen this area under the label of the brain's "Somatosensory Strip."

 

The Lobes of the Cerebral Cortex


Occipital Lobe

Occipital animated   [Occipital Lobe]


Parietal Lobe

Parietal AnimatedParietal Lobe   [Somatosensory
              strip]



Temporal lobe

Temporal animated     [Temporal Lobe]

  • putting many types of objects in the mouth,
  • emotional placidity,
  • hyper/inappropriate sexual advances, and
  • distractability caused by small objects.


Frontal Lobe

   Frontal animated[Frontal Lobe]

Prefrontal Cortex: Executive Control. integrate a large amount of data involving "executive" planning and judgment, emotional modulation, and other tasks.

[Brain size]

Involved with working memory: short-term information (rather than long-term factual data) & responding to delayed-response tasks (needing to respond to what is remembered after a short delay)

Control of behavior that depends upon context or setting. Damage shows itself in impulsivity or inappropriate responses. For example, do you look through the desk drawers in someone else's home? What difference does it make to your behavior if you are in a sports arena or your local church?


[Lobotomy]

[Leucotomy]
Lobotomy/Psychosurgery

From the late-1930s to the mid-1950s, physicians performed prefrontal lobotomies.

Developed in Europe, but pioneered in the U.S. by a physician, Dr. Walter Freeman. It was used with about 40,000 patients

Freeman
                      studying xray



Putting It Together: The Binding Problem
 
[The Harvest]      [Relativity]
 Which one of these pictures is easier to view as a whole?

V. Ramachandran: Mirror Box Therapy






Occipital animated image: "BodyParts3D, © The Database Center for Life Science licensed under CC Attribution-Share Alike 2.1 Japan."
Parietal animated image: "BodyParts3D, © The Database Center for Life Science licensed under CC Attribution-Share Alike 2.1 Japan."
Temporal animalted image: "BodyParts3D, © The Database Center for Life Science licensed under CC Attribution-Share Alike 2.1 Japan."
Frontal animated image: "BodyParts3D, © The Database Center for Life Science licensed under CC Attribution-Share Alike 2.1 Japan."