A clouding of the natural lens of the eye is called a cataract. There are three types of age-related cataracts---nuclear, cortical and posterior subcapsular---that can develop as people get older, according to The Eye Digest. Each type of cataract...
Cortical cataracts are one type of age-related cataract that is also common in patients with diabetes. A cortical cataract forms in the cortex, which is one layer of the eye's natural lens; these cataracts tend to look like spokes and can cause...
A cortical stroke occurs when the blood supply to the outside, or cortex, of the brain is reduced or blocked, which results in brain damage. The National Institute of Neurological Disorders and Strokes states that the cortex is the main processing...
Cortical dysplasia is a congenital brain defect in the cortex area. The Hemispherectomy Foundation states that this disorder is diagnosed in infancy or early childhood, though it can also show up in rare cases in adolescence. In addition to the...
Your kneecap, or patella, is surrounded by a hard, dense shell of cortical bone. A rehabilitation protocol for cortical knee surgery -- which involves the kneecap -- focuses on pain reduction; ambulation, or walking; and exercises to strengthen...
The adrenal glands are a set of two structures that sit atop the kidneys. The adrenal glands are endocrine glands, which produce and secrete several hormones that can signal to a number of tissues throughout the body. Cancer of the adrenal cortex,...
When you exercise, blood flow increases throughout your body, including the brain. Cardiovascular exercises elevate the heart rate more effectively than other workouts. With faster blood flow, the brain receives extra oxygenation for increased...
Stories of how meditation improves quality of life are as old as the practice itself. Martial artists have used meditation to improve physical performance. Monks have used it to achieve enlightenment, union with the divine and equanimity with the...
Alzheimer's is a progressive neurodegenerative condition, chiefly defined by the steady accumulation of toxic protein masses called amyloid plaques and neurofibrillary tangles in areas of the brain necessary for processing factual information. Due...
The brain consists of different regions that have distinct functions but communicate with each other. The brain consists of the cerebral cortex, brain stem and cerebellum. The cerebral cortex is further broken down into four lobes: the frontal,...
Attention Deficit Hyperactivity Disorder (ADHD) is a neurobehavioral disorder that is characterized by attention-related problems and hyperactivity. ADHD is the most commonly diagnosed mental disorder that affects about 3 to 5 percent of...
Runners experience reduced pain perception due to a phenomenon known as the "runner's high." While you are in this state, not only is your mood elevated, but chemical reactions induced by strenuous exercise act as a natural painkiller. For...
Tactile disorders, or sensory processing disorders, affect the sense of touch. In these disturbances, sensation may be felt too intensely or too subtly, or objects may in various ways seem unrecognizable when held in the hand. Tactile disorders...
When you begin to exercise, your heart pumps faster, your muscles burn and your breathing quickens. Multiple body systems work in synchrony to help your body perform efficient, coordinated physical exercise. While exercise has some effect on most...
Brain derived neurotrophic factor plays a key role in how easily your brain can adapt to and learn how to effectively complete new challenges, called neuroplasticity. Brain derived neurotrophic factor acts as a fertilizer of the brain's neurons,...
Dopamine functions as a chemical messenger in three major brain circuits, namely the nigrostriatal, mesolimbic and mesocortical systems. The nigrostriatal system extends from the substantia nigra and terminates in the brain's motor control...
Theanine is an amino acid found in tea leaves that may have various health benefits for those who use it. In Japan, green tea has especially high concentrations of theanine, and it has been used to treat the symptoms of attention deficit...
The distribution of cone types, types of cells in the retina that detect different wavelengths of light, varies greatly among different individuals, says University of Rochester professor David Williams. Williams and his team used a laser-based...
Zinc in the proper amounts plays a crucial role in neurological function. However, too much zinc can be as harmful as too little. On the one hand, appropriate levels of zinc supplementation can improve mental function in children who are likely to...
Senile cataracts are a clouding of the lens in the eye that develops with aging. More than 70 percent of people over age 75 have some degree of lens clouding, according to Richard Lindstrom, M.D., of ImproveYourVision.com. Senile cataracts can...
Almost all people experience dreaming, and many reference dreams in conversation, literature and artistic expression. An emerging field is the biology and psychology of dreaming. Recent discoveries have provided insight into the anatomical...
A stroke occurs when oxygen is restricted to a portion of the brain for enough time to cause damage. This may be due to a blood clot or blockage in one of the brain's blood vessels, or a burst blood vessel in the brain. When damage occurs in the...
A cataract is a clouding of the lens in the eye. The lens, found behind the iris and the pupil, focuses light on the back of the retina. Cataracts differ by type and cause. More than 50 percent of people over age 80 either have a cataract or have...
If your monthly premenstrual symptoms have grown more intense and difficult to bear, you may be suffering from premenstrual dysphoric disorder, or PMDD, a severe and sometimes disabling form of premenstrual syndrome. PMDD occurs in up to 8 percent...
A stroke is a potentially life-threatening neurological incident that involves disruption of the blood supply to a part of the brain. Affecting people of all ages, strokes can potentially lead to long-term brain damage and disability. While few...
Migraines are a type of extremely severe headache that can occur periodically over the course of many years. According to the experts at the Mayo Clinic, it is not exactly understood what causes migraine headaches, but it appears to be a mixture...
Medical researchers classify dementia into two broad categories, under which there are several known versions of the disease. These are cortical and subcortical dementias. Essentially, dementia in general is an impairment of your mental processes....
Estrogen is a group of sex steroids produced by the ovaries of females and the testes of men. Estradiol is the main estrogen hormone involved in bone mineral density for both genders. Levels of estradiol can vary depending on your stage of life....
An occipital stroke occurs when the occipital lobes of the brain are damaged due to a lack of oxygenated blood. A stroke is often caused by problems with blood flow in the brain, such as a blocked artery or an artery that has burst. Damage to the...
Photosensitivity is an abnormal sensitivity of the skin to ultraviolet light, usually following exposure to certain oral or topical drugs or to other sensitizing chemicals and resulting in accelerated burning and blistering of the skin. Learn...
Adrenal gland cancers are rare cancers occurring in the endocrine tissue of the adrenal glands and are characterized by overproduction of adrenal gland hormones. Learn about the symptoms and treatment options in this video.
