Is it Possible to Have a Two-Way Conversation With a Severed Head?

Call us morbid, but we've always wondered whether a decapitated head can still see for any length of time after being severed. Fortunately, we discovered that we aren't the first people who've scratched their heads over this curiosity.
In the early 19th-century France (back when being guillotined was more or less a rite of passage), a series of scientists investigated the question. They concluded that decapitated heads continued to respond to external stimuli for several seconds after, um, parting from their respective bodies. For instance, some heads would look you in the eyes if you called their names. In fact, researchers theorize that you can have a "conversation" with a decapitated head for about 10 to 12 seconds. Lung-less, the head can't talk, but it can blink to answer yes or no.
That said, we're guessing a decapitated head wouldn't be in any mood to answer questions.