Anatomy of the Brain - Cerebral Cortex Function

The cerebral cortex is the thin layer of the brain that covers the outer portion (1.5mm to 5mm) of the cerebrum. It is covered by the meninges and often referred to as gray matter. The cortex is gray because nerves in this area lack the insulation that makes most other parts of the brain appear to be white. The cortex also covers the cerebellum.

The cerebral cortex consists of folded bulges called gyri that create deep furrows or fissures called sulci.

The folds in the brain add to its surface area and therefore increase the amount of gray matter and the quantity of information that can be processed.

The cerebrum is the most highly developed part of the human brain and is responsible for thinking, perceiving, producing and understanding language. Most information processing occurs in the cerebral cortex. The cerebral cortex is divided into four lobesthat each have a specific function. These lobes include the frontal lobes, parietal lobes, temporal lobes, and occipital lobes.

CEREBRAL CORTEX FUNCTION

The cerebral cortex is involved in several functions of the body including:

• Determining Intelligence
• Determining Personality
• Motor Function
• Planning and Organization
• Touch Sensation
• Processing Sensory Information
• Language Processing

The cerebral cortex contains sensory areas and motor areas. Sensory areas receive input from the thalamus and process information related to the senses.

They include the visual cortex of the occipital lobe, auditory cortex of the temporal lobe, gustatory cortex and somatosensory cortex of the parietal lobe. Within the sensory areas are association areas which give meaning to sensations and associate sensations with specific stimuli. Motor areas, including the primary motor cortex and the premotor cortex, regulate voluntary movement.

CEREBRAL CORTEX LOCATION

Directionally, the cerebrum and the cortex that covers it is the uppermost part of the brain. It is superior to other structures such as the pons, cerebellum and medulla oblongata.

CEREBRAL CORTEX DISORDERS

A number of disorders result from damage or death to brain cells of the cerebral cortex. The symptoms experienced depend on the area of the cortex that is damaged. Apraxia is a group of disorders that are characterized by the inability to perform certain motor tasks, although there is no damage to motor or sensory nerve function. Individuals may have difficulty walking, be unable to dress themselves or unable to use common objects appropriately. Apraxia is often observed in those with Alzheimer’s disease, Parkinson's disorders, and frontal lobe disorders. Damage to the cerebral cortex parietal lobe can cause a condition known as agraphia. These individuals have difficulty writing or are unable to write. Damage to the cerebral cortex may also result in ataxia. These types of disorders are characterized by a lack of coordination and balance. Individuals are unable to perform voluntary musclemovements smoothly. Injury to the cerebral cortex has also been linked to depressive disorders, difficulty in decision making, lack of impulse control, memory issues, and attention problems.

MORE INFORMATION

For additional information on the cerebral cortex, see:

• Functional Divisions of the Cerebral Cortex
• Cerebral Lobes

DIVISIONS OF THE BRAIN

• Forebrain - encompasses the cerebral cortex and brain lobes.
• Midbrain - connects the forebrain to the hindbrain.
• Hindbrain - regulates autonomic functions and coordinates movement.

This article originally appeared on thoughtco.com and was written by Regina Bailey

Rhythm of Breathing Affects Memory and Fear

Summary: A new study reports the rhythm of your breathing can influence neural activity that enhances memory recall and emotional judgement.

Source: Northwestern University.

Breathing is not just for oxygen; it’s now linked to brain function and behavior.

Northwestern Medicine scientists have discovered for the first time that the rhythm of breathing creates electrical activity in the human brain that enhances emotional judgments and memory recall.

These effects on behavior depend critically on whether you inhale or exhale and whether you breathe through the nose or mouth.

In the study, individuals were able to identify a fearful face more quickly if they encountered the face when breathing in compared to breathing out. Individuals also were more likely to remember an object if they encountered it on the inhaled breath than the exhaled one. The effect disappeared if breathing was through the mouth.

“One of the major findings in this study is that there is a dramatic difference in brain activity in the amygdala and hippocampus during inhalation compared with exhalation,” said lead author Christina Zelano, assistant professor of neurology at Northwestern University Feinberg School of Medicine. “When you breathe in, we discovered you are stimulating neurons in the olfactory cortex, amygdala and hippocampus, all across the limbic system.”

The study was published Dec. 6 in the Journal of Neuroscience.

The senior author is Jay Gottfried, professor of neurology at Feinberg.

Northwestern scientists first discovered these differences in brain activity while studying seven patients with epilepsy who were scheduled for brain surgery. A week prior to surgery, a surgeon implanted electrodes into the patients’ brains in order to identify the origin of their seizures. This allowed scientists to acquire electro-physiological data directly from their brains. The recorded electrical signals showed brain activity fluctuated with breathing. The activity occurs in brain areas where emotions, memory and smells are processed.

This discovery led scientists to ask whether cognitive functions typically associated with these brain areas — in particular fear processing and memory — could also be affected by breathing.

Article originally appeared on http://neurosciencenews.com/memory-fear-breathing-5699/