Damage to Broca's area in the frontal lobe causes difficulty in speaking and writing, a problem known as Broca's aphasia. Injury to Wernicke's area in the left temporal lobe results in an inability to comprehend spoken language, called Wernicke's aphasia. Cerebral palsy is a broad term for brain damage sustained close to birth that permanently affects motor function. The damage may take place either in the developing fetus, during birth, or just after birth and is the result of the faulty development or breaking down of motor pathways. Cerebral palsy is non-progressive that is, it does not worsen with time. During childhood development, the brain is particularly susceptible to damage because of the rapid growth and reorganization of nerve connections. Problems that originate in the immature brain can appear as epilepsy or other brain-function problems in adulthood.
Parkinson's Disease, progressively disabling neurological disease marked by tremor and increasing stiffness of the muscles. The onset of this disease is gradual, which makes it difficult to diagnose in its early stages. Tremor usually begins in one or both hands; eventually the thumb and forefinger may show a rapid repetitive movement described as "pill rolling." In addition to muscular rigidity, other symptoms include slow body movement, poor coordination, and faulty balance. A shortening of muscles along the front of the neck tends to bend the head and spine forward, while the lack of animation in the face creates a mask like expression. As these symptoms worsen, chronic fatigue, mental confusion, and speech impairment may develop and the person with Parkinson's may find it impossible to walk unassisted.
The symptoms of Parkinson's disease appear when neurons (nerve cells) located in the substantia nigra, a part of the brain stem, either die or lose their ability to function properly. The chief neurotransmitter—or carrier of nerve signals—in this area of the brain is dopamine, which is deficient in people who have Parkinson's. The cause of this deficiency is not known, but research suggests that several factors may reinforce each other to produce Parkinson's disease. There may be a genetic predisposition for some forms...