The Human Brain And Methods Of Discovery

The Human Brain And Methods Of Discovery Essay, Research Paper The Human Brain and Methods of Discovery The human nervous system consists of several parts. The main structures are the brain and the spinal cord. The system includes nerves that sense external and internal stimuli and then relay the information to the central processing unit — the brain. The brain is the portion of the vertebrate central nervous system that constitutes the organ of thought and neural coordination. It includes all the higher nervous centers, receiving stimuli from the sense organs and interpreting and correlating them to formulate the motor impulses. It is made up of neuronal cells, supporting and nutritive structures, and is enclosed within the skull. The brain is continuous with the spinal

cord through the foramen magnum – the opening in the skull through which the spinal cord passes to become the medulla oblongata. The knowledge we have of brain structure, function and interrelativity has been substantially accelerated over the last century. This is largely due to advances in nuclear medicine technological advances in noninvasive methods of studying and viewing brain structure and the actual ability to visually measure live neural activity in relation to activity. The scope of this paper is to discuss brain scanning and to then discuss some of the structures and functions of the brain whose discovery this technology has made possible. X-ray machines have been the chief mechanical tools for internal observations of the human body since Wilhelm Roentgen discovered

X-rays in 1901. The development of computers made it possible for better and more accurate techniques to be applied to scan the human body. These methods employ various scanners like the CT (computerized tomography), PET (positron emission tomography), MRI (magnetic resonance imaging) and SPECT (single photon emission computed tomography). The CT is an acronym for computerized tomography. This method of scanning involves computer-enhanced X rays of brain structures, shot from many angles and then combined by the computer to render a clear image of a horizontal slice of the brain. Doctors and scientists are able to view the three dimensional format on a computer screen. MRI stands for magnetic resonance imaging. This scan uses magnetic fields, radio waves and computer enhancement

to provide much better images of brain structure and function than CT scans. Once called nuclear magnetic resonance imaging, the “nuclear” was dropped off because of fears that people would think there was something radioactive involved, which there is not. MRI is a way of getting pictures of various parts of the body without the use of X rays, unlike regular X ray pictures and CT scans. An MRI scanner consists of a large and very strong magnet in which the patient lies. A radio wave antenna is used to send signals to the body and then receive signals back. These “radio wave signals” are actually a varying or changing magnetic field that is much weaker than the steady, strong magnetic field of the main magnet. These returning signals are converted into pictures by a

computer attached to the scanner. Pictures of almost any part of your body can be obtained at almost any particular angle. PET stands for positron emission tomography, and it is much more complicated than the CT scan. A PET scans is a medical imaging technique that provides images of biochemical function over time. This enables researchers to map which areas of the brain become active to specific stimuli. PET machines bombard the subject with doses of positrons: the anti-matter equivalents of the electrons. As the positrons enter the body, they encounter electrons that are escaping from radioactive elements that have been injected into the bloodstream. When the positrons and the electrons collide, they give off energy that is recorded by a computer. The result of this scan is a