Playing tennis in a coma.

To begin, Corinne Barham assesses 23-year-old Chris, who has been in a coma for several years, for signs of consciousness. Neuroscientists Professor Martin Monti, Dr Srivas Chennu, Joseph Vinson and Professor Anil Seth explain how we typically detect whether somebody is conscious, how somebody might fall into a vegetative state, and the different levels of consciousness within that state. Presenter Kate Lamble visits Patricia and Trudie, wife and daughter of 75-year-old John, who fell into a vegetative state after contracting encephalomyelitis. Lamble then visits Gordon and Adam, Chris father and brother. Barham describes how electroencephalography (EEG) equipment is being used in the study. Chennu further explains the main goal of the study. Barham explains the trials and tribulations of working from raw data. The families talk about their experiences attempting to communicate with Chris and John. Seth discusses the challenges of trying to construct a concrete scientific explanation for consciousness, and a way of measuring it. Monti and Dr Adrian Owen explain Owens thought experiment study, in which volunteers were asked to imagine playing tennis within an fMRI scanner in order to explore how different types of brain activity can be visualised during conscious thought. Medical Ethicist Dr Joseph Fins discusses this further. Barham, Chennu and Fins discuss how this study manages the hopes and expectations of the families involved. Chennu reveals some preliminary results from the study to the families of Chris and John. Lamble and Chennu discuss the impact of these results, on the study and, in particular, on the families involved.