The external brain
The brain may be affected by a head injury or stroke. Symptoms may be subtle, such as difficulty concentrating, or severe, with weakness or paralysis of limbs, speech and understanding difficulties, and even seizures. A nerve may be injured by an accident or by “Repetitive trauma“ (an accumulation of damage from overuse) as is commonly seen in the condition called “Carpal tunnel syndrome”. The role of the neurologist is to diagnose the problem accurately and determine the best course of treatment. There have been many advances in this field. Extrapolating these further makes interesting predictions and reading.

The Internal Brain
Brain cells replaced throughout life
For most of this century, scientists believed that the human brain grew until a certain age, then stopped – Making learning more difficult in later years. Now, researchers have evidence that the part of the brain most closely associated with complex learning and memory, the cerebral cortex, continually regenerates itself.

A study published in the journal Science explores the growth of new brain cells. The study suggests that new treatments for brain diseases and injuries may be possible in the future. On a more basic level, the research disputes the view that mental challenges are a natural part of old age.

New conclusions
Scientists have been building toward this conclusion for several decades. The idea of the never-changing brain was challenged as early as the mid-1960s and early 1970s, when experiments showed that the nervous systems of Slugs and other animals could change their structure over time by altering their network of brain cells. Later, experiments showed evidence of the generation of new brain cells – A process called neurogenesis – In adult rats, mice and dogs. In this decade, scientists have also found neurogenesis in several types of adult monkeys and even in adult humans. But these finding were limited to portions of the brain that are believed to affect a less crucial role in the highest brain functions.