Oec Magazin (A1-b)

things, and there’s also related work at Oxford and London. But Zurich really is something special in this regard. It’s the only place to have a neuro- imaging lab as part of its economics department», says Ruff. That crucial enabler is the Laboratory for Social and Neural Systems Research – or SNS Lab for short – a multimillion Swiss franc facil- ity built in the bowels of the university hospi- tal. Founded in 2007, the first experiments began two years later. In a hushed, subterranean, world of sub- dued lighting, volunteers assist the team in re- searching how decisions are made and on social behaviour in general. While there is plentiful worldwide medical and biochemical research into the continuing mysteries of the brain, the SNS Lab’s work is entirely non invasive and fo- cused on the interaction of brain and environ- ment. «Medical research has focused on things like the impact of a haemorrhage or on biochem- ical reactions inside the brain. What’s been really missing is some sort of unifying function, which is what our research is trying to provide», says Ruff. Revealing altruism, fairness and trust Volunteers face a series of questions designed to identify which parts of the brain work in dif- ferent types of decision making, and how those regions change under differing circumstances. The research is conducted with two main tools, a powerful magnetic resonance imaging machine (fMRI), providing real time pictures of the brain functioning, and electroencephlographic (EEG) equipment recording the brain’s electric activity. The two are complementary: while fMRI provides remarkably detailed images to locate decision making neural activity, EEG, involving sensors attached to the scalp, is less precise for location but far more accurate in terms of speed of operation. Depending on the question, experiments use either or both techniques. Volunteers in the fMRI machine are shown images on a screen and asked to react via a ba- sic keyboard – rather like a first generation games player. The questions involve simple choices, like whether to take SFr20 for sure or accept the risk of receiving either SFr40, or nothing. Inquiries can grow more sophisticated, gradually incorporat- ing features such as trust and fear. Non-financial choices, like deciding between a tempting, but un- healthy, candy bar, and a dull, but wholesome, al- ternative, can also be presented. The fMRI scanner tracks differences in oxygen levels in the brain’s bloodstream – a proxy for neural activity – show- ing how brains react. The neural activity reveals which part of a brain is stimulated by different decisions. Volunteers can also be given audible, olfactory or liquid sensations, or even have their skin stimulated in different ways, such as scratch- ing or stroking. The volunteers themselves cover a spectrum of sex, age, character and lifestyle. Financial inducements are used because they are universal, explains the team. «One has to use something rewarding, something that people want to receive. Money is good for that», says To- bler. Food is also appropriate, but can be trickier given taste differences. «We try to make decisions «We’re trying to iden- tify the biological mecha- nism behind decision making and to how those may change with context or time.» Prof. Christian Ruff Christian Ruff, Professor of Neuroeconomics and Decision Neuroscience, Department of Economics Philippe Tobler, Assistant Professor of Neuroeconomics and Social Neuroscience, Department of Economics 14 Oec. Juli 2015 FOKUS

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