Levin et al. Neuropsychology of risky gains/losses high probability but risk-seeking for gains and risk-aversion for losses of low probability (Tversky and Kahneman, 1992). This was explained in terms of underweighting the likelihood of high prob- ability but overweighting the likelihood of low probability events. The tasks described in this paper will primarily be of the for- mer type. This paper describes a relatively new component of this research: neuroscientiﬁc studies that provide additional sources of data that separate risk-taking to achieve a gain and risk-taking to avoid a loss. In presenting the most recent research in our laboratory, we focus on the “cups task” (Levin et al., 2007), which we devel- oped speciﬁcally to separate risky decision-making for actual gains and losses, both in terms of overall riskiness and sensitivity to expected value (EV) differences between choice options. The cups task includes a gain domain and a loss domain. Gain trials involve some probability of an addition to the decision-maker’s account while loss trials involve a possible reduction. Decision makers choose between one array of cups in which the outcome is constant (the riskless choice) and one array of cups in which the outcomes vary (the risky choice). Outcomes are displayed immediately after choices are made. By varying the number of cups and the amount to be won or lost, we create gain and loss trials with contingencies that either do or do not favor a risky choice (see Figure 2). For example, a one-out-of-three chance of winning ﬁve coins is better in the long run than a sure gain of one coin but a one-out-of-three chance of losing ﬁve coins is worse in the long run than a sure loss of one coin. A key component of data analysis for the cups task is the extent to which an individual makes choices based on the con- sideration of relative EV between choice options, for both gain- and loss-related decisions. EV sensitivity represents an index of advantageous decision-making because consistently choosing the option with a more favorable EV will yield more positive outcomes in the long run. As will be described later, a somewhat simpler version of the task was adapted for use in scanner research. Across many data sets, we demonstrated that Kahneman and Tversky’s (1979) original ﬁnding of more risk-taking to avoid a loss than to achieve a gain of the same magnitude is reproduced in the cups task. Beyond the initial demonstration of greater risk-taking for losses than for gains, our recent research with the cups task showed age-related differences in risk-taking as a function of deci- sion domain (risk-taking to achieve a gain versus to avoid a loss). Risk-taking in the domain of gains decreased monotonically from early childhood to older adulthood whereas overall risk-taking to avoid losses was remarkably constant across age groups (Weller et al., 2011). Within both domains, EV sensitivity increased from early childhood through adulthood with a slight decline for older adults. EVIDENCE FROM DECISION NEUROSCIENCE We turn to neuroscience for an exploration of brain functions that may help explain these gain/loss behavioral differences. Our approach in this paper is to provide a body of evidence that is consistent with the proposition that risky decision-making is sep- arable in the gain and loss domains rather than providing a single “critical” test. Historically, the most fundamental functional division of the brain was thought to be the one that distinguished between approach and avoidance behaviors. However, many years of animal research failed to identify anatomically separate neural substrates– neural systems underlying pain and pleasure seem to overlap considerably (e.g., Craig, 2009). Later human behavioral stud- ies found equivocal support for a separation of neural systems whereby the left hemisphere is predominantly concerned with approach behaviors and the lure of reward, whereas the right hemi- sphere is critical for avoidance behaviors and the fear of uncer- tainty (Davidson et al., 1990). More recently, neuropsychological FIGURE 2 | Samples of trial types on the cups task. Note: in each case the “riskless” side is depicted on the left and the “risky side” is depicted on the right. In the experiments these were counterbalanced over trials. www.frontiersin.org February 2012 | Volume 6 | Article 15 | 3