How does neuropsychological assessment and screening work? - Chapter 10Topic 10A Neurobiological Concepts and Behavior AssessmentThe Human BrainThe brain is the best protected organ in the body. It is first protected by the skull. Then through meninges, three membranes that cover the brain and spinal cord. In the brain, the ventricles are filled with cerebrospinal fluid. This is a liquid that is constantly produced and refreshed and serves as protection for the brain. The brain literally floats up here and is protected against blows and dehydration. The ventricles are four hollow, connected chambers in the middle of the brain. It may be that the aqueduct leaving the 3rd or 4th ventricle becomes too small. This can be a problem from birth or develop throughout adulthood. This condition is known as hydrocephalus or water head. The pressure then becomes too large in the brain. In children it can cause the ventricles to grow and the brain is eventually pressed against the skull. Untreated, this can lead to mental retardation or premature death. Fortunately, it is easy to treat the excess liquid through a shunt to drain.When the brain is surrounded by the liquid, it weighs about 1.5 kilos. The brain consists of 5 elements: gray matter, white matter, glial cells, cerebrospinal fluid, and the blood vessels that supply the brain with oxygen and nutrients.The brain constantly needs oxygen and glucose through blood. The blood is transported through a circular network of arteries called the circle of Willis. This network ensures that the brain is constantly supplied with blood. When one gets older it can happen that one of the arteries becomes silted up by fatty plaques. Then oxygen is missing and an infarct occurs, which is a kind of stroke or cerebrovascular accident. One can also develop later multi-infarct dementia , which is the result of an accumulation of small infarcts over a number of years. It can also happen that a blood vessel breaks open...