alan mayberry has done a wonderful imaging on depressed people. if you look at psychiatry, for example, there is no area that is really understood on this level. autism, we're just beginning to understand which areas of the brain are involved. >> we have not been able to do this before because we did not have the tools to do it like we do now? the imaging tools, or is it some new theory? theory. is no new the imaging tools that came along were noisy and not completely reliable. it took a long time to really work out the difficulties with them. they are now much more reliable, and this is a very reliable group of investigators, number one. number two, you need huge resources to carry out these large gayle studies. the problem is extremely difficult. she is asking herself, how does the brain function in very general terms? how do people handle the same task in somewhat different ways? >> explain this to me. you have said the central question is how do differences between you and me and how our brains are wired up relate to differences in our behavio