Science at the Movies

When you go to the cinema, you often have to leave your ‘scientist hat’ at home. Spending the duration of Star Wars penning an angry letter to George Lucas about the inability of sound to travel in space sucks most of the fun out of the film. For most of us, it is not hard to suspend our disbelief for a while and overlook these discrepancies – and nobody really likes that guy who whispers loudly to his friends, “actually, according to the laws of physics…” But sometimes, when a dubious scientific idea forms the basis of an entire film, it is a little harder to ignore.

Take last year’s blockbuster, Limitless. In the film, Bradley Cooper plays a struggling author who stumbles upon a drug which gives him access to the ‘full 100%’ of his brain – as opposed to the 10% or so that is supposedly the limit of our normal use. Now able to utilise all of his brain, Bradley is not only able to overcome his writer’s block, but also quickly learn new languages and instruments. He is even able to earn a fortune overnight through a new-found talent for stock trading.

You’ve probably heard the rather unscientific claim that we only use 10% of our brain before. What constitutes ’10 percent’ is rather unclear, and by some measures the claim is so widely off the mark that it is surprising it has been so pervasive. Its fallacy can be shown by examining what happens after damage to the brain. While humans may sometimes function well after considerable brain damage, changes are usually seen no matter where the damage occurs. This is clearly exemplified in data we have from stroke patients. Thousands of people suffer from strokes each year, and even a small area of damage can cause profound difficulties with functions such as language and movement. If any abilities are regained it can take months of rehabilitation. These strokes are certainly not confined to a mere 10% of the brain, so from a physical or neuroanatomical perspective, it is clear that all of the parts of our brain are important.

The misconception may have arisen from early observations of the brain’s cellular construction. Approximately 10% of the cells in the brain are neurons, cells which transmit information via electrical and chemical signals. The remaining cells are called glia, traditionally thought to play a more passive and supportive role in the brain, providing sustenance to neurons and guiding their growth (have a look at Nicola Platt’s article for more insight into glia). From this perspective it could be argued that only 10% of the brain cells (i.e. the neurons) are used for information processing. Of course, we are still ‘using’ the glia cells. They are vital for neural functioning, and recent research has demonstrated that they are in fact directly involved in signalling themselves.

So where does that leave Limitless? It is clear that physiologically, the premise of the film makes no sense. Of course, cognitive enhancing drugs do exist, and while their effects may currently be far removed from those portrayed in the film, Limitless does bring up important questions about the ethical implications of such drugs. It’s just a shame that the science is wrong.