Manipulating Brains

The desire to manipulate brain function is not new. In manipulating brain function the goal is to manipulate behaviour and we have been manipulating behaviour for the whole of our evolution as social animals. Primates, such as ourselves, living in social groups carry out mind manipulation with astonishing speed and accuracy throughout the day. We are all a little friendlier, some unknowingly,others less so, when we want something. We manipulate each other’s wishes, patience, value judgments and beliefs. We are so good at it that we can do it en masse: The smell of bread in the supermarket entrance, the classy music in a clothes store, and the promise of instant health on a snack bar wrapper are all ways of manipulating behaviour and thus the nervous system. Some are real masters of this sort of manipulation and succeed in leading entire nations into huge successes or horrible abominations. For most of us, basic techniques on how to master such manipulations of others to maximize personal success can be learned from the like of Dale Carnegie and his 1936 classic“How to Win Friends and Influence People” [1]. So, if we can manipulate the behaviour of individuals and populations so subtly and successfully, why do we struggle in our attempts to help stroke victims walk and talk? If it is so easy to make people want things, why is it so hard to make them learn things? And if we can manipulate minds so naturally, why can we not construct machines, therapies and drugs to do it too? The answer is twofold and encapsulates the problems, which the papers in this issue try to address. The first part of the answer is that the most successful machine for mind manipulation is another mind: our brains are optimized for the sending and decoding of social signals by millions of years of evolution. The second part of the answer is that the evolution of minds for mutual mind manipulation has proceeded entirely on the basis of the outcome of attempts at manipulation – for one mind to manipulate another requires no knowledge of the mechanisms operating in that mind. Our struggle to comprehend these mechanisms by understanding the biological basis of the mind leaves us with at least three problems: How to physically manipulate brain structure and function; how to achieve longterm effects of our interventions;and how to understand the integrated nature of brain function while having the goal of achieving behaviourally local effects. The premise behind this issue of Behavioural Neurology is that it is both possible and in a clinical context desirable to influence brain function and that it can serve to improve behaviour and promote recovery of function. As brain imaging techniques improve, scientist are becoming increasingly likely to eventually predict, by examining a scan of a person’s brain, whether he or she will tend to depression or violence, or whether he or she has talents in certain areas. We are likely to learn not only about the brain areas involved in lying, working responsibly, and acquiring new skills with far greater precision than we know now, but also how to change them to enhance or suppress their function and hence manipulate behaviour. Neural implants may within a few years be able to increase in-