“…Therefore, we surmised that the finding of the putamen, whose rGMD was linked to dispositional optimism, may reflect the motivational characteristics of dispositional optimism. More concretely, the putamen has been demonstrated to be involved in several motivation‐related processes, for example, history‐based reward value encoding, action selection, and cue‐action‐dependent reward prediction (Elliott, Newman, Longe, & Deakin, ; Haruno & Kawato, ; Hori, Minamimoto, & Kimura, ; Kunimatsu, Maeda, & Hikosaka, ; Mizuno et al, ; Muranishi et al, ; Pessiglione, Seymour, Flandin, Dolan, & Frith, ; Schultz, ). For example, several studies have shown that the putamen was closely associated with reward value encoding and action selection based on past experience (Kunimatsu et al, ; Muranishi et al, ), and that these processes, i.e., history‐based reward value updating and action selection, were impaired if the neural activity in the putamen was blocked (Muranishi et al, ).…”