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How brain scans reveal what really goes on in our minds [excerpt]

Every year in March, Brain Awareness Week champions the global campaign to celebrate and publicise the progress and benefits of brain research. Uniting the efforts of research hospitals, universities, government agencies, and professional organizations, from around the world BAW shines a light on the human brain from the latest technological techniques in neuroimaging to cutting edge improvements in medical intervention for psychiatric disorders.

In the excerpt below from Sex, Lies, and Brain Scans, Barbara Sahakian and Julia Gottwald explain how fMRI is changing the diagnosis and treatment of conditions such as Obsessive Compulsive Disorder.

Are you lying? Do you have a racial bias? Is your moral compass intact? To find out what you think or feel, we usually have to take your word for it. But questionnaires and other explicit measures to reveal what’s on your mind are imperfect: you may choose to hide your true beliefs or you may not even be aware of them.

But now there is a technology that enables us to “read the mind” with growing accuracy: functional magnetic resonance imaging (fMRI). It measures brain activity indirectly by tracking changes in blood flow. Your brain is constantly active, even when you sleep. This activity changes depending on what you do. If you start a new task, the brain areas involved in this process will alter their activity. If a brain area becomes more active, it needs energy, and so more oxygenated blood will flow in this region thus making it possible for neuroscientists to observe the brain in action. Because the technology is safe and effective, fMRI has revolutionised our understanding of the human brain. It has shed light on areas important for speech, movement, memory and many other processes.

Researchers are beginning to unravel the brain circuits involved in self-control, morality, sexual arousal, and lying. Some of us may want to use this knowledge to screen for criminals or use fMRI scan data as evidence in a murder trial or detect racial biases. But we must keep in mind that fMRI has many limitations. It is not a crystal ball. We might be able to detect an implicit racial bias in you, but this cannot predict your behaviour in the real world.

fmri machine
01 Siemens MAGNETOM Trio by Image Editor. CC-BY-2.0 via Flickr.

An exciting development is that of real-time fMRI. With this technique, neuroimaging data can be analysed online while the subject is still in the scanner. This analysis can be used to give the subject feedback about their brain activation in real time, so-called neurofeedback. Such feedback can be used to learn how to actively control your brain activation, for example to control your perception of pain.

Innovative study designs have helped to make neuroimaging studies more realistic. A recent study led by our colleague Paula Banca from the University of Cambridge used live video material while the participants were in the scanner. The aim of the research was to learn more about the neural basis of obsessive–compulsive disorder (OCD). These patients suffer from compulsions (repetitive behaviours the patient feels compelled to carry out) and/or obsessions (intrusive, distressing thoughts that enter the patient’s mind). In so-called symptom-provocation designs, researchers try to trigger such obsessions or compulsions to find out what is happening in the patient’s brain. Such knowledge is important for a deeper understanding of disorders and to develop new treatments. These obsessions and compulsions differ between individuals—not every patient is afraid of germs or feels compelled to clean excessively. It is therefore important to design these symptom-provocation studies in such a way that they trigger the personal obsessions and compulsions of the patient.

Our colleagues developed a creative new design: the researcher went to the patient’s home and, with the permission of the patient, performed actions that were tailored to the patient’s symptoms. For example, for a patient concerned with symmetry and organization, the researcher would mess up their sock drawer or bed. Live video material of this disorganization was then streamed and shown to the patient, who was undergoing fMRI. Patients were free to stop the procedure at any time. The researchers found that the ventromedial prefrontal cortex, an area behind the forehead, acts as the key region in a circuit modulating compulsivity. Such a creative approach can give us new insights into the underlying neural circuits of obsessions, compulsions, and many other conditions.
What new possibilities and insights will fMRI offer? And what ethical dilemmas might result?
While many applications are still science fiction, they might become reality sooner than we imagine. We will need to decide how and where we want to allow mind-reading or neuromarketing.
Should we screen for (implicit) racial bias with the help of neuroimaging? Does fMRI-based lie detection violate the privacy of thought? Should we test how moral or self-controlled a person is to prevent future crimes?

These are just some of the important ethical questions that will need to be debated and answered by society as a whole.

Featured image credit: IMG_9549.CR2 by Stephen Hampshire. CC-BY-2.0 via Flickr.

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