Lecture 2 - Through a glass darkly
Just by looking at the brain, it is impossible to guess what it is doing. So how can we study it? The Greeks reasoned that air is the most insubstantial substance there is, and so the lungs must be the most appropriate place for our insubstantial thoughts and emotions. However, once it was accepted that the brain was the place in the body where mental activity was generated, then alternative, equally 'logical', theories ensued: for example, the fluid that bathes the brain and spinal cord was not solid like brain tissue, and thus was regarded as the seat of the soul. More recently, in the last century, the 'phrenologists' hit on the idea of allocating certain character traits to individuals according to the bumps on their head. However, this approach was discredited when it was found that the alleged centre for 'language' did not correspond to a brain area damaged in a real patient. The study of patients with brain damage has ever since provided a host of clues as to how the brain works. Another, completely different approach is to compare the skulls of the predecessors of Homo sapiens and also to identify the similarities and differences in the brains of other species. However, one of the most fruitful ways forward is to study the real brain at work. It is now possible to view on a screen images of the living brain of a conscious person as they read, think, and solve problems. According to the task being performed, different parts of the brain use up more energy, are visibly more active than other parts. We are now at a stage to ask to what extent the brain works like a computer, or indeed whether a computer could ever be conscious. The answers to these issues remain open to debate.
About the 1994 CHRISTMAS LECTURES
Then Dr Susan, now Baroness Greenfield (b.1950), presented the 1994 CHRISTMAS LECTURES as a five-part series, entitled 'Journey to the Centres of the Brain'. Our brains are ourselves. Every emotion, prejudice and hope is grounded in a molecular scenario somehow and somewhere in the secretive, silent organ between the ears. These lectures will explore what we know, and what still mystifies us, about the workings of the brain. Starting with no prior knowledge, we shall see what the brain looks like, how it generates electricity, and how it uses chemicals to process information. We shall be left with the thought that we know a great deal about how different brain regions function, but how such regions work together to generate a cohesive, individual individual consciousness, remains a tantalising puzzle.