, 2011), premotor cortex (Pastor-Bernier and Cisek, 2011), and medial prefrontal cortex (Sohn and Lee, 2007; Seo and Lee, 2009; So and Stuphorn, 2010). Many of these brain areas might in fact encode the signals related to utilities of reward expected from specific actions, even when the probabilities and timing of reward vary. For example, temporally discounted values are encoded by neurons in

the prefrontal cortex (Kim Selleckchem Trichostatin A et al., 2008), posterior parietal cortex (Louie and Glimcher, 2010), and the striatum (Cai et al., 2011). Human neuroimaging experiments have also identified signals related to utilities in multiple brain areas, including the ventromedial prefrontal cortex (VMPFC) and ventral striatum (Kuhnen and Knutson, 2005; Knutson et al., 2005;

Knutson et al., 2007; Luhmann et al., 2008; Chib et al., 2009; Levy et al., 2011). Consistent with the results from single-neuron recording studies (Sohn and Lee, 2007), signals related to values of reward expected from specific motor actions have been identified in the human supplementary motor area (Wunderlich et al., 2009). Activity in the VMPFC and ventral striatum display additional characteristics of value signals used for decision making. For example, the activity in each of these areas is influenced oppositely by expected gains and losses. In addition, activity in these areas is more enhanced for expected losses than for expected gains, and this difference is related to the level of loss aversion across individuals (Tom et al., 2007). Activity in the VMPFC and ventral BMS-354825 striatum also reflects temporally discounted values for delayed reward during inter-temporal choice (Kable and Glimcher, 2007; Pine et al., 2009). Results from neuroimaging and lesion studies also suggest that the amygdala might play a role in estimating value functions according to potential losses. For example, activity

in the amygdala changes according to whether a particular outcome is framed as a gain or a loss (De Martino et al., 2006), and loss aversion is abolished in patients with focal lesions in the amygdala (De Martino et al., of 2010). Whether decisions are based on values computed for specific goods or their locations, and which brain areas encode the value signals actually used for action selection, might vary depending on the nature of choices to be made (Lee et al., 2012). The DLPFC might contribute to flexible switching between different types of value signals used for decision making. This is possible, since the DLPFC is connected with many other brain areas that encode different types of value signals (Petrides and Pandya, 1984; Carmichael and Price, 1996; Miller and Cohen, 2001). In addition, individual neurons in the DLPFC can modulate their activity according to value signals associated with specific objects as well as their locations (Kim et al., 2012b).