Compare and contrast the techniques researchers use to study the brain. Explain what type of information can be gained by each approach.

Question

What will be an ideal response?

Answer 1

One way researchers have learned more about the brain is by studying the effects of brain lesions or brain damage. By examining the person or animal that has the lesion, researchers get a sense of the function of the part of the brain that was damaged. Electroencephalograph (EEG) involves recording the brain's electrical activity. Researchers also might use one of several brain-imaging techniques. Computerized axial tomography (CAT scan or CT scan) involves the use of X-rays to produce a composite three-dimensional image and can provide information about the location and extent of brain damage. Positron-emission tomography (PET scan) is another brain-imaging technique that is based on metabolic (glucose) changes related to brain activity. Magnetic resonance imaging (MRI) involves creating a magnetic field around a person's body and using radio waves to construct images of the person's tissues and biochemical activities. MRI scans provide valuable information about the structure of the brain and can allow researchers to see if and how experiences affect brain structure. Although MRI scans can reveal considerable information about brain structure, they cannot portray brain function. A new method known as functional magnetic resonance imaging (fMRI) allows scientists to see what is happening in the brain while it is working. The fMRI charts track changes in blood oxygen that occur in association with brain activity.