A man is beheaded "cleanly" - perhaps by guillotine. Is it possible that there follows a period of awareness, albeit of only a few nanoseconds?

NeilH, Bath, UK

• The answer, horribly, is 'Not only is it possible, but it's medically proven.' Debate on the subject raged ever since Charlotte Corday -- the assassin of Jean-Paul Marat -- was guillotined in 1793. The executioner's assistant, Francois le Gros, lifted her head by the hair, and slapped it on both cheeks. Eyewitnesses reported that the face took on an angry expression, and the cheeks visibly flushed. The debate was started -- if guillotining didn't produce instant death, then it wasn't a 'quick and merciful end', as promised by the post-Enlightenment revolutionaries. In 1794, German surgeon Dr S. T. Sommering argued in the Parisian newspapers that 'consciousness of feeling may persist [in a severed head] even if blood circulation is terminated, partial or weak [...] the head's strongest sensation would be the after-pain felt in the neck.' French doctors argued that he was confusing nervous spasms with sensory perceptions and voluntary motion. Little research was conducted on the subject, however, until the turn of the twentieth century, when another French doctor, Beaurieux, was permitted to make an investigation of a severed head, of a criminal called Languille, immediately after guillotining: "Here is what I was able to note immediately after the decapitation: the eyelids and lips of the decapitated man worked in irregularly rhythmic contractions for about 4 or 6 seconds. I waited several seconds longer. The spasmodic movements ceased. The face relaxed, the lids half-closed in the eyeballs, leaving only the white of the conjunctiva visible, exactly as in the dying whom we have occasion to see every day [...] It was then that I called in a strong, sharp, voice: 'Languille!' I then saw the eyelids slowly lift up, without any spasmodic contraction -- I insist advisedly on this pecularity -- but with an even movement, quite distinct and normal, such as happens in everyday life, with people awakened or torn from their thoughts. Next, Languille's eyes very definitely fixed themselves on mine and the pupils focused themselves. I was not, then, dealing with a vague dull look, without any expression that can be observed any day in dying people to whom one speaks: I was dealing with undeniably living eyes which were looking at me." By 1956, further research had proved, in the words of governemntal advisers Drs Piedelievre and Fournier, that "death [by decapitation] is not instantaneous [...] every vital element survives [...it is] a savage vivisection, followed by a premature burial." The French government abolished execution by decapitation in 1977.

  Garrick Alder, London

• The higher functions of the brain cease activity once the blood supply, and therefore oxygen transport, is interrupted. Usually there is about 4 or 5 seconds of consciousness following the complete cessation of the circulation. This would be more than enough time for the severed head to fall into the basket and roll around a few times before blessed oblivion arrived.

  J.W.Perry, West Vancouver, BC, Canada

• The higher functions of the brain cease activity once the blood supply, and therefore oxygen transport, is interrupted. Usually there is about 4 or 5 seconds of consciousness following the complete cessation of the circulation. This would be more than enough time for the severed head to fall into the basket and roll around a few times before blessed oblivion arrived.

  J.W.Perry, West Vancouver, B.C., Canada.

• I once read an infrantyman's eye witness account of seeing his comrade sliced in two at the waist during the FIrst World War, in which he claimed that the legs continued to run for several steps before falling to the floor (Lyn Macdonald - Thay called it Passchendaele, I think it was).

  Emily Adams, Bristol UK