Cerebral Cortex Information in this presentation is taken from UCCP Content

Cerebral Cortex The cerebrum is the largest part of the brain. Only in humans does the cerebrum account for such a large portion of the brain. It is responsible for cognitive abilities such as thinking and language. The cerebrum consists of two hemispheres: the left and right hemispheres. The hemispheres are connected by the corpus callosum, a bundle of nerve fibers. The surface or outer coating of the cerebrum is the cerebral cortex. The cerebral cortex is convoluted; it’s wrinkled with ridges and valleys that allow for a lot of surface area to be packed into a small area of the brain.

Cerebral Cortex Each hemisphere of the cerebral cortex is divided into 4 lobes: 1)The occipital lobe contains the primary visual cortex and is responsible for processing visual information. 2)The temporal lobe contains the primary auditory cortex and is responsible for processing auditory information. 3)The parietal lobe contains the sensory cortex, which receives sensory information from the skin and other body movements. 4)The frontal lobe contains the motor cortex and the prefrontal cortex.

Cerebral Cortex Each location in the sensory cortex represents touch sensations and body location information from a different body part. The entire body is mapped on the cortex. The top of the cortex begins with your toes and each body part has a location along the cortex until it reaches the face and tongue. The sensory cortex on the right side of the brain receives sensations from the left side of your body whereas the mirror image on the left side of your brain receives information from the right side of your body. There are more neurons responsible for receiving sensory information about the face and the head than there are neurons for receiving sensory information about the trunk of the body and the legs. This is one reason why our face and head are more sensitive to touch than other parts of our body.

Cerebral Cortex Each location in the motor cortex regulates our movement of a different body part. The motor cortex lies next to the fissure that separates the frontal and parietal lobes and each body part is assigned a position on the cortex in the mirror image of the sensory cortex. The prefrontal cortex is comprised of many association areas, the areas of the cerebral cortex that are not primarily involved in sensation and motor activity. These association areas are involved in various aspects of higher order thinking, including short-term memory, planning, setting goals, creative thinking and decision- making.

Cerebral Cortex Behaviors Try to determine which section of the cerebral cortex is responsible for the behaviors being explained (answers on following slide): 1)Throughout the day, Peter repeatedly has skin sensations of a spider crawling on his right arm. When he went to brush it off, nothing was there. Doctors found he had damage to his _________________. 2)Julie became unconscious after the back of her head was slammed against the seat of the car in an accident. She was blind when she awoke at the hospital. A neurological exam found she had damage to the _________________. 3)When Rebecca fell down some stairs, she hit the left side of her head on the concrete. She initially had ringing out of her left ear. It was concluded she most likely had damage to her ______________. 4)After having being in a tragic accident, Bob was never the same. He had difficulty making decisions or plans and he began acting in a socially inappropriate manner. A PET scan showed he had damage to the ___________________.

Answers 1)Parietal lobe or sensory cortex 2)Occipital lobe 3)Temporal lobe 4)Frontal lobe or prefrontal cortex