We have also long had more scientific ways of measuring emotional response, such as examining a subject's heart rate and perspiration levels using the same technology as lie detectors (though these techniques are far less widely used in political psychology). There are some problems with both of these techniques, of course; people may not be willing or able to describe their emotions with precision, and the use of older technologies to tap emotional responses involves ethical as well as financial issues, as well as being rather imprecise and unsuitable for some purposes. As we shall see in the next chapter, developments in neuroscience-most notably in brain imaging techniques such as MRI and fMRI-have made it easier than before to measure directly the emotions that individuals are experiencing, however. Moreover, political psychologists have begun to work with neuroscientists at an interdisciplinary level to utilize such techniques in their work. While this work is very new indeed and the results of the few studies done so far are extremely preliminary, in the next chapter we will examine and assess some of the latest research that has been done in this area.