J. Peters & C. Büchel Overlapping and distinct neural systems code for subjective value during intertemporal and risky decision making. Supplemental Material Supplemental Methods Experiment 2 Subjects Healthy young subjects (n = 18, mean age = 25.8, 11 male) took part in Experiment 2. Subjects provided informed written consent, and the study procedure was approved by the local Ethics committee. Behavioral pre-tests As in Experiment 1, subjects completed two behavioral pretests (DD of 20€ and PD of 20€) to estimate discount rates. Task Subjects made choices between 20€ available with a given delay and 20€ available with a given probability. Delay-probability combinations were computed based on the most recent discount functions from behavioural pre-tests. The construction of trials involved the following steps: 1) Calculation of the minimum subjective value available for trial generation using the following equation min( sv ) = max (min [sv _ delays ], min [sv _ probabilit ies ]) (3). 2) The interval [min_sv 1] was then divided by the number of trials (132). For each of these values, the corresponding delay and probability were calculated based on the hyperbolic discount functions obtained in the last behavioural session, i.e. the total subjective value range was identical for the delayed and probabilistic options, but differed between participants, depending on their discounting behaviour. 3) Delay-probability combinations were then constructed by combining the highest subjective value delay with the lowest subjective value probability, the second-highest subjective value delay with the second-lowest subjective value probability, and so on for the entire subjective value range. Therefore, in 50% of trials, the probabilistic option had the greater subjective value, whereas in the remaining trials, the delayed option had the greater subjective value. As in Experiment 1, participants were told that one of their choices would be randomly selected following the testing session, and that they would receive 20€ with the state delay/probability as an Amazon.de email gift certificate. Subjects performed two sessions of 66 trials each. Each trial started with the presentation of a green dot signalling the start of the trial. Then, the delayed and the probabilistic options were presented (duration 2s each) in randomized order. A random inter-trial interval was included (2-6 s sampled from a uniform distribution) and, following the second option, subjects were prompted to select their preferred option (“A or B”). Data analysis We analyzed participants’ choice behaviour as a function of the subjective value difference between the delayed and the probabilistic option. The subjective value range of presented options depended on participants’ choice behavior during behavioural pretests (see above). To account for these differences, we computed the difference between option values (subjective value [delayed option] – subjective value [probabilistic option]) and scaled this measure according to the individual subjective value range of each participant. The resulting difference measure thus reflects the difference between option values in terms of proportion of the individual value range of subjects (see Fig. 7). This difference measure was then split into 10 bins (ranging from -0.5 to +0.5) and the proportion of delayed choices was calculated 1 for each bin (see Fig. 7b). We next fit a logistic function of the form f (x) = ()1 + be −cx (4) to these data points for each individual subject. Based on this function, we then estimated the value difference at which participants were indifferent between the delayed and probabilistic option. The group mean of this measure was compared to zero using a one-sample t-test. Supplemental Results Experiment 1 Supplemental Table 1 Delays and probabilities used for behavioral and fMRI testing. Delay Immediate 6 hours 1 day 7 days 30 days 90 days 180 days Reward Probability 100% 99% 96% 84% 54% 28% 17% Supplemental Table 2 Subjective value correlation for delay discounting (p < 0.001, uncorrected, k > 10 voxels) in the primary GLM Region MNI coordinates z-value L lateral parietal cortex -58 -46 36 5.72 -54 -56 46 4.06 -50 -54 36 3.88 L ventral striatum -8 4 -8 5.29 -18 -6 -12 3.86 R lateral parietal cortex 54 -42 26 4.98 R inferior/middle frontal gyrus 54 40 -4 4.84 48 36 -12 3.77 R middle temporal gyrus 70 -36 2 4.49 66 -30 -2 4.29 58 -40 -2 3.31 R medial prefrontal cortex / anterior 12 46 6 4.44 cingulate cortex R central orbitofrontal cortex 28 16 -18 4.41 Posterior cingulate -2 -46 32 4.33 R inferior temporal gyrus 50 -22 -20 4.17 L medial frontal gyrus / frontal pole -8 52 16 4.05 -2 58 24 3.80 L inferior frontal gyrus -34 32 12 4.02 -44 14 12 3.78 -52 14 8 3.70 R inferior frontal gyrus 36 30 -16 3.83 L caudate -18 16 12 3.81 L middle temporal gyrus -66 -30 -6 3.69 -64 -32 2 3.20 R middle frontal gyrus 54 6 42 3.53 Supplemental Table 3 Subjective value correlation delay discounting > probability discounting (p < 0.001, uncorrected, k > 10 voxels) in the primary GLM Region MNI coordinates z-value L lateral parietal cortex -58 -50 34 5.11 1 R medial prefrontal / anterior 12 42 4 3.86 cingulate R lateral parietal cortex 64 -42 28 3.81 54 -40 26 3.67 L medial frontal gyrus / frontal -10 54 16 3.74 2 pole L middle temporal gyrus -62 -14 -10 3.68 Posterior cingulate -4 -48 32 3.48 3 L inferior frontal gyrus 52 38 -6 3.48 1 sub-peak [-56, -56, 28, z-value = 3.34] significant at p = 0.031, FWE-corrected across 8 mm sphere based on peak coordinates [-56, -60, 22] reported by Kable & Glimcher (2007) 2 sub-peak [-2 54 26, z-value = 3.18] signifincant at p = 0.048, FWE-corrected across 8 mm sphere based on peak coordinates [4, 58, 26] reported by Addis et al. (2007) 3 p = 0.056, FWE-corrected across 12 mm sphere based on peak coordinates [-1, -40, 35] reported by Kable & Glimcher (2007) Supplemental Table 4 Subjective value correlation for probability discounting (p < 0.001, uncorrected, k > 10 voxels) in the primary GLM Region MNI coordinates z-value 42 -38 44 5.26 R/L superior/inferior parietal lobule 40 -46 42 4.95 -36 -52 46 4.88 L ventral striatum / thalamus -8 4 -8 5.13 -6 -20 10 4.60 6 -12 6 4.41 L middle occipital gyrus -48 -62 -10 5.10 -58 -48 -10 3.33 -52 -44 -14 3.21 Precuneus / posterior cingulate 0 -34 42 4.98 -4 -34 26 4.07 6 -20 32 4.06 R insula / inferior / middle frontal 44 8 26 4.87 gyrus 36 4 30 4.74 52 10 18 4.43 L visual cortex -12 -96 -6 4.76 -16 -92 0 4.63 -24 -72 -8 4.40 L precentral / inferior / middle -42 -2 30 4.73 frontal gyrus -48 6 28 4.37 -50 6 42 4.15 R inferior frontal gyrus 46 36 10 4.50 42 30 20 3.47 R middle temporal gyrus 56 -54 -10 4.43 48 -56 -10 4.27 46 -56 -20 3.47 L insula / inferior frontal gyrus -26 18 0 4.41 L medial frontal gyrus -18 60 4 4.15 -24 56 0 3.63 L anterior cingulate / medial -4 38 -8 4.13 frontal gyrus 4 40 -2 4.07 R cerebellum 22 -50 -24 4.01 L inferior / middle frontal gyrus -44 42 8 3.99 -40 36 14 3.83 -38 24 20 3.62 L cerebellum -12 -76 -24 3.94 R inferior / middle frontal gyrus 26 34 -14 3.93 30 18 -6 3.67 24 24 -10 3.62 L inferior / middle frontal gyrus -22 34 -18 3.80 -14 40 -16 3.68 -20 26 -18 3.60 L midbrain -6 -30 -8 3.77 R cerebellum 10 -80 -26 3.76 L lingual gyrus -14 -38 -2 3.69 R Thalamus 18 -18 14 3.67 R visual cortex 12 -80 6 3.64 6 -80 18 3.40 0 -76 8 3.36 R central orbitofrontal cortex 26 18 -16 3.62 R inferior / middle occipital 38 -82 -4 3.62 gyrus R inferior / middle frontal gyrus 54 30 18 3.59 R midbrain 4 -28 -16 3.54 R middle frontal gyrus 28 18 44 3.50 R middle frontal gyrus / anterior 6 28 -10 3.46 cingulate R temporal pole 48 20 -18 3.43 L anterior cingulate -10 28 30 3.41 L insula -26 10 -18 3.30 Mid-cingulum 2 2 38 3.29 Supplemental Table 5 Subjective value correlation probability discounting > delay discounting (p < 0.001, uncorrected, k > 10 voxels) in the primary GLM Region MNI coordinates z-value L visual cortex -16 -92 0 5.01 -4 -86 -6 4.01 R inferior/superior parietal lobule 42 -38 44 5.00 32 -48 44 4.67 32 -60 54 4.03 Right precentral gyrus / inferior frontal gyrus 38 2 30 4.62 44 6 26 4.25 L middle occipital gyrus -48 -64 -10 4.14 L parahippocampal gyrus -14 -38 -2 4.02 R lingual / precunes / post. cingulate 22 -56 -2 3.98 12 -70 10 3.49 16 -60 6 3.42 R Middle temporal gyrus 56 -54 -10 3.92 48 -56 -10 3.71 L inferior frontal gyrus/insula -26 18 0 3.86 L precuneus -22 -72 50 3.81 L cuneus -32 -76 34 3.76 -28 -84 32 3.25 R cerebellum 24 -50 -26 3.75 L posterior cingulate -18 -56 12 3.75 -14 -54 4 3.35 R Precuneus 8 -72 46 3.73 R visual cortex 16 -96 8 3.73 14 -94 18 3.31 L precentral gyrus -42 -2 30 3.73 L thalamus -20 -26 -2 3.71 Post.