Mapping the Human Brain – the Challenges Faced

Sophia David

The human brain is made up of billions of neurons that communicate with each other via trillions of connections. Together, they make up a network of unimaginable intricacy. Perhaps it is not surprising then, given this complexity, that things frequently go wrong within the brain. Approximately 1 in 4 people suffer from a diagnosable mental health disorder within any given year and as many as five million Americans now live with Alzheimer’s disease.

Unfortunately, drugs to treat brain disorders have been slow to materialize. Many large pharmaceutical companies have withdrawn their research on mental health diseases due to the length of time it takes these drugs to be developed and the high failure associated with them. Essentially, to big pharma, the field is unattractive and economically not viable.

Our inability to effectively treat brain disorders is unsurprising given how little scientists know about the brain’s workings. Neuroscientists have mapped the broad anatomy of the brain and gathered small pieces of information such as which brain areas are active during certain tasks. However, many big questions remain. What makes us our individual selves? Why do brain disorders or mental health problems arise in some individuals? Given, the apparent rise of mental health illnesses and the subsequent burden on our health systems, we have an urgent need to develop new approaches for treating brain disorders.

To address this problem, two huge research programs to develop our understanding of the brain have been launched this year. The first is Barack Obama’s BRAIN Initiative (Brain Research through Advancing Innovative Neuro-technologies) and the second is the European Commission’s Human Brain Project. The two $1 billion projects are highly ambitious and the challenges faced cannot be underestimated. But most will agree they have the potential to completely revolutionize neuroscience, if successful.

The BRAIN scientists are hoping to map each of the brain’s 100 billion neurons, its 100 trillion synapses and chart the function and activity of each. That’s no easy feat considering we currently lack the technology to map the brain in any significant detail at all. Therefore, the first step in both programs is to develop these new tools.  It is hoped that by producing images of neural circuits within the brain and by visualizing neural interactions in real-time, we can start to develop our understanding of how the workings of the brain are linked to behavior, movement, learning and emotions. Then, of course, the ultimate goal is to unravel the mechanisms of brain disorders.

Each of these programs is expected to cost around $1 billion, a huge sum in an era where many scientists are strapped for cash. Some neuroscientists have voiced concerns that these large, top-down approach programs may drain money away from other smaller hypothesis-driven projects in individual labs. The two programs are certainly high risk, and some are concerned that the money could end up being wasted in failed schemes. Therefore, there are calls for the funding to come from genuinely new money and not encroach on funding for neuroscience research performed by individual groups.

Along with any discoveries, the two human brain projects are also likely to throw up a whole new array of ethical issues. How should an individual’s own brain data be used, and how should it be protected? What happens if we become able to predict neuro-degenerative diseases in individuals? Should we be predicting them if they remain untreatable? How should cognitive enhancement devices be used? A study published in Science a few weeks ago (found here: also alarmed some scientists by showing how false memories could be implanted in mice. What if the same could be attempted in humans? Thus, there are many issues to be debated and it is crucial that a new set of ethics standards is established before data begins to be produced.

Inevitably, parallels between these large-scale human brain projects have been drawn with the Human Genome Project (HGP), the world’s first venture into “big science”. The HGP began in 1990 with a clear goal of establishing the three billion base pairs of the human genome in order, a project that was completed thirteen years later. The HGP has undoubtedly revolutionized the field of genetics, and many claim that the brain projects will do the same for neuroscience. However, the applications of having a complete genome sequence were better defined. For example, scientists would be able to search for disease-causing mutations and identify genes associated with diseases with far greater ease. However, while the latest brain projects have a clear goal in that they wish to simultaneously map and record the activity of a large number of neurons, the implications of this information are perhaps less clear. Will it solve how the brain works?  We may have to wait ten years to find out.