Scanners and skyscrapers
fMRI is everywhere. Not a day goes by without reading of another claim employing this wonderful brain scanning tool. Functional Magnetic Resonance Imaging observes regional brain activity by identifying changes in blood-flow to neurons. By peering into the head, it can detect the moment-by-moment changes in our thoughts as bright bursts of neural fireworks. The map it charts is a moving inner landscape – a tangled forest of axons and dendrites that somehow holds our conscious selves. If recent news is taken at face value, then fMRI can now tell if you are lying. It can tell if you fancy someone. It can presumably tell if you’re lying about fancying someone. It knows when you’re happy. It knows what choices you’ll make even before you’ve made them. FMRI is the new oracle. The All-Seeing Eye. The infallible inquisitor. If Orwell’s 1984 was set in 2010, then the Thought Police could simply fire up the fMRI machine.
But is it all that simple? Have we found the last word in measuring inner thoughts and motivations? Are all those messy qualitative musings of psychology now redundant? I have my doubts. In the burst of scientific excitement surrounding this device, I sense the stale old whiff of hubris. FMRI is a wonderful tool. But a great tool can sometimes lure the best human minds into the false promise of universal applicability. “If my device can do A, B and C, then surely it can tell us all about D – Z”.
Well… not necessarily.
Abraham Maslow’s well-trodden quote springs to mind here:
“When the only tool you have is a hammer, every problem begins to resemble a nail”
I have constructed a clumsy analogy to explain what I think are the limits of fMRI in trying to decode higher-level human cognition and motivation. It’s not perfect, so please bear with me.
Imagine you live near to a skyscraper in the financial district of a large city. You know that the building houses a major investment bank. You watch its workers enter and exit every day. You read its announcements in the news, and monitor its share price. But you can’t enter the building, and you know little of its internal organisation. Now imagine that you have a special camera trained on this building. The camera records the activity in the building by noting the office lights that turn on and off on each particular floor of the skyscraper when staff are busy in the rooms. Also you have some powerful friends, who are able to engineer particular external events that may have a bearing on this bank.
You want to learn as much as you can about the ethos of this organisation. Its deepest motivations. The way the boss thinks, and why. So you embark on an experiment to find out.
It’s surprising how much you can learn. By watching the building every night, you note that most lights go off except in an area on the ground floor. This is obviously where Security is situated. When the Tokyo stock market is open, there are always lights burning in a particular area of floor 32. You conclude that this is the Asian trading floor. In this way, the organisational geography of the building soon becomes clear. And by combining effects, more sophisticated things are discovered. A negative press story engineered by your friends produces frantic activity between the boardroom, the press office and the trading floor. Calm announcements by the CEO are contrasted with the nervous activity betrayed in the building. A lack of light in the conference room in late December shows that the Christmas party has been cancelled. Lights burning after hours on certain floors indicate those departments that fear redundancy. A company personality begins to emerge – the pattern of lights displaying responses to stimuli in a way that seems to indicate personal fears, thoughts and motivations within the building.
The next day, the CEO purchases an oil painting from Sotheby’s to hang in her office. She pays a huge fee for this work, saying only that the painting has a special meaning for her. You know the subject of this composition. You’ve been told its importance to her. You know the location of the painting in the building. Your camera can see the light in her office burning long into the night as she examines it. But you don’t know why she bought it. What she’s thinking as she looks at it. Only that she’s thinking – because the light in her room is on. You can’t see her childhood memories in these lights. You can’t see the face of her father. You can’t detect the subtle combination of fragmentary memory and emotion that led her to purchase the work at such expense. So you conclude from your lights that the CEO has responded to the recent company pressures visible in the building by making an extravagant status purchase. This indicates a clear personality trait in the CEO – a tendency to run away from the problems of the organisation. The painting is simply a factor of the story that the lights have told. It has no story of its own. Stimulus – response. Hammer – nail.
Yet how could the light machine know about the anniversary of her father’s death? Or the blue on the canvas that matches her father’s eyes? Or the content of those inspiring words that come back to her when looking at the painting?
fMRI is truly powerful. Applied intelligently, it gives immense insights into brain function. fMRI may be the best hammer we’ve made so far. But that doesn’t mean it can turn every beautiful secret of the human mind and consciousness into a nail.