Neuroscience, Chapter 1 Neuroscience: Past, Present, and Future Introduction The Society for Neuroscience was founded as recently as 1970. The study of the brain, however, is as old as science itself. Most people involved in the scientific investigation of the nervous system regard themselves as neuroscientists. The Origins of Neuroscience 7000 years ago – evidence of skull surgeries while patients were still alive May have been to treat headaches or mental disorders In ancient Egypt, the brain was simply scooped out of the dead and discarded, the heart was thought to be the base of thought and consciousness Views of the Brain in Ancient Greece There is a very clear correlation between structure and function of the different parts of the body Thus differences in appearance predict differences in function In the fourth century B.C., Greek scholars concluded that the brain is the organ of sensation Hippocrates stated that the brain not only was involved in sensation but was also the seat of intelligence Aristotle however clung to the belief that the heart was the center of intellect Views of the Brain During the Roman Empire Galen embraced the Hippocratic view of brain function. He was a physician to the gladiators. He also dissected animals and their brains Galen tried to deduce function from the structure of the cerebrum and the cerebellum Galen cut the brain open and found that it was hollow. In these hollow spaces, called ventricles, there is fluid. To Galen, this discovery fit perfectly with the prevailing theory that the body functioned according to a balance of four vital fluids, or humors. Views of the Brain from the Renaissance to the Nineteenth Century Descartes was a chief advocate of the fluid-mechanical theory of brain function which said that fluid forced out of the ventricles through the nerves might literally “pump you up” and cause the movement of the limbs. He did not think however that this could account for the full range of human behavior. He reasoned that unlike animals, people possessed a God-given soul Thus, brain mechanisms control human behavior only to the extent that this behavior resembles that of the beasts. Uniquely human mental capabilities exist outside the brain in the “mind” Today, some people still believe that the mind and brain are separate however neuroscience research supports the conclusion that the mind has a physical basis which is the brain. Other scientists began to focus on the difference between the gray matter and the white matter of the brain An important breakthrough in neuroanatomy was the observation that the same general pattern of bumps and grooves could be identified on the surface of the brain in every individual This pattern, which enables the parceling of the cerebrum into loves, was the basis for speculation that different functions might be localized to the different bumps on the brain Nineteenth Century views of the brain The new concept was the nerves are “wires” that conduct electrical signals to and from the brain. Unresolved was whether the signals to the muscles causing movement use the same wires as those that register sensations from the skin. It was known that within each nerve of the body there are many thin filaments, or nerve fibers, each one of which could serve as an individual wire carrying information in a different direction. Neuroscience today The levels of analysis are broken down into Molecular Cellular Systems Behavioral Cognitive Neuroscientists Neuroscience research is divided into two types Clinical Usually conducted by physicians Experimental Neuroanatomists Neurophysiologists Neuropharmacologists Molecular neurobiologists The scientific process Consists of four essential steps Observation Replication Interpretation Verification The use of Animals in Neuroscience Research The animals The number of animals used for all types of biomedical research is less than 1% of the number that are killed for food alone The number used for neuroscience research is much smaller still Experiments are conducted using many different species ranging from snails to monkeys Today more than half of the animals used for neuroscience research are rodents that are bred specifically for this purpose Animal welfare Animals are used for worthwhile experiments that promise to advance our necessary knowledge of the nervous system All necessary steps are taken to minimize pain and distress experienced All possible alternatives to the use of animals are considered Animal rights Often confused with animal welfare, animal rights activists have sometimes destroyed years of hard work when in fact the procedures done on the animals have saved lives. The cost of ignorance: nervous system disorders Some disorders that affect the nervous system Alzheimer’s disease Cerebral palsy Depression Epilepsy Multiple sclerosis Parkinson’s disease Schizophrenia Spinal paralysis Stroke The annual cost of care for people with dementia is approximately $100 billion Depression is the leading cause of suicide As many or more Americans are hospitalized with neurological and mental disorders than with any other major disease group, including heart disease and cancer.