<p>It depends on what you want to do. If you want to be a neuroscientist, in a department of neuroscience or a department of psychology or some other more traditional university department, a PhD is going to be far more desirable than an MD. I don’t know any neuroscience/neurobiology or related field professors with an MD. Furthermore, I would dispute the idea that working up the ladder is easier with an MD. Most top administrators in universities are PhDs, with the exception of administrators at medical centers (specifically medical schools).</p>
<p>However, if you want to do research at a medical center or research complex - and you wouldn’t mind teaching in a medical school - then either is fine, and an MD might be more desirable. You can do the same kind of research as you would with a PhD, just that you’d more likely do it either at a medical center or an interdisciplinary research institute as a full-time researcher or as a medical professor.</p>
<p>Generally speaking, MDs are not designed to be research degrees. Most people who intend a research career as an MD intend a very applied focus to their research and intend to combine research with practice. I go to an academic medical center in public health, and the MDs who do research here generally have a private or group practice (or work in a community health clinic) in addition to their teaching and research responsibilities.</p>
<p>In reference to #8, A PhD does not last twice as long as an MD. PhD students in the natural sciences can normally expect about 4-6 years of study before they graduate. What’s more, PhD programs typically come with a tuition waiver and a stipend, so a graduate of one should leave with little to no debt.</p>