The Cerebral Cortex

Thin outer layer of interconnected neurons that are responsible for higher level thinking & skills

The Evolving Brain

• Different animal species have many structures in common, including a cerebellum and cortex.
• The cortex is much larger in mammals than in species that evolved earlier, such as fish and amphibians.
• The cross section of the human brain shows how the cerebral cortex has developed around and above more primitive brain structures.

​

When it comes to Cortex…�Size DOES Matter

• If flattened, a human cortex would cover about four pages of your textbook.
• A chimpanzee's would cover one page
• a monkey's a postcard
• a rat's a postage stamp.
• From Scientific American, October 1994, p. 102.

Association Areas of the Cortex

• More intelligent animals have increased "uncommitted" or association areas of the cortex.
• These areas used for integrating and acting on information received and processed by sensory areas.
• Allows for learning, thinking, memory & adaptability

Forebrain Structures

Largest Brain Region with the most complex structures.

What separates us from the beasts.

2 hemispheres are�divided into 4 lobes

Frontal Lobe

​

​

​

​

• Important in judgment, planning and sequencing
• Controls emotional center of the brain (limbic system)
• Prefrontal area for working memory (Short-Term Memory)
• Helps you remember what you just did so you know what to do next (sequencing)

​

​

​

Temporal Lobe

• Contains primary auditory cortex – interprets hearing info
• Helps with Recognition
• speech recognition
• face recognition (Fusiform Gyrus)
• word recognition
• memory formation

​

Occipital Lobe

• Contains primary visual cortex
• Makes sense of visual info it receives from the optic nerve

Parietal Lobe

• Contains primary somatosensory cortex
• “Skin” sense of touch and temperature.
• Processes body position

Lobes of the Cortex

• Frontal lobe - largest lobe, involved in thinking, planning, emotional control, voluntary muscle movements
• Temporal lobe - auditory information, recognition
• Occipital lobe - visual information
• Parietal lobe - sensory information from your body & muscles

Motor & Somatosensory Cortex

Motor Cortex: Located at the back of the Frontal Lobe.

​

The more precise movements, the more motor cortex the part uses up.

Sensory Cortex:

Located at the front of the Parietal Lobe.

​

The more sensitive the area, the more sensory cortex it uses up.

Language and the Brain

• Broca’s area—plays role in speech production
• Wernicke’s area—plays role in understanding and producing meaningful speech

​

• Aphasia—partial or complete inability to articulate ideas or understand language because of brain injury or damage

Broca’s Aphasia

• Damage to Broca’s Area causes a person to struggle formulating words while still being able to comprehend speech.
• frequently speak in short, meaningful phrases that are produced with great effort
• Example: Broca first discovered this area when he had a patient with damage to this area who could only say “tan”
• Example:  Affected people often omit small words such as “is,” “and,” and “the.” For example, a person with Broca’s aphasia may say, “Walk dog” meaning, “I will take the dog for a walk.” The same sentence could also mean “You take the dog for a walk,” or “The dog walked out of the yard,” depending on the circumstances.
• Click HERE for a video example of Broca’s Aphasia

Wernicke’s Aphasia

• – Damage to Wernicke’s Area would cause a person only to be able to speak in meaningless words.
• Example: Asked to describe a picture of two boys stealing cookies from behind a woman’s back, a patient responded:
• “Mother is away her working her work to get her better, but when she’s looking the two boys looking the other part. She’s working another time.”
• Example: Someone with Wernicke’s aphasia may say, “You know that smoodle pinkered and that I want to get him round and take care of him like you want before,” meaning “The dog needs to go out so I will take him for a walk.”
• Individuals with Wernicke’s aphasia usually have great difficulty understanding speech and are therefore often unaware of their mistakes.
• Click HERE for a video example
• Mnemonic to remember: You can't read Wernicke's words and Broca's makes you breaks up your speech.

​

Language Areas of the Brain

How We Read Out Loud