Figure 5.
Weights of influence of expected value differences on choices of X relative to Y. A, Log-normalized mean weights and SEM of beta weights from the main effects of VX, VY, and VD are plotted from a GLM controlling the interactions between option values for Controls, mOFC/vmPFC, lOFC, and DMF. There is a positive influence of Vx, and a negative influence of VY, on choosing X over Y in all subject groups. B, The GLM is rearranged to isolate the effect of the expected value of the irrelevant (“distractor”) third option on the value difference between X and Y. Controls are plotted against mOFC/vmPFC (Bi), DMF (Bii), and lOFC (Biii). Biv, mOFC/vmPFC and lOFC patients are replotted. “o,” Individual subject scores. Biv, Black “o,” subject whose lesion affects both mOFC/vmPFC and lOFC. Statistics for direct comparisons between mOFC/vmPFC and lOFC lesions leave out this subject. High expected values of the irrelevant third option significantly reduce the influence of VX − VY on choice only in mOFC/vmPFC (Bi) and DMF (Bii) groups relative to Controls. lOFC patients do not differ from Controls in the effect of the expected value of the third option (VD) on their choices between X and Y (Biii). *Denotes statistical difference.