Medial rostral prefrontal cortex and the neuroeconomics of

Medial rostral prefrontal cortex and the neuroeconomics of mental time travel Roland G. Benoit Sam J. Gilbert Paul W. Burgess University College London

imagining the future Addis, Wong, & Schacter, 2007 subjective value Kable & Glimcher, 2007 metanalysis Gilbert et al. , 2006

Task Imagine the episode of spending the money in the scenario Estimate what the money could buy you in the scenario Episodic prospection Semantic prospection Arithmetic operations X X X Counting Count forwards (backwards) from the X indicated number in steps of 3 (4) 5 amounts [£: 26; 33; 42; 52; 65] X 4 delays [days: 30; 90; 180; 360]; 20 scenarios 1 s * 2 s Imagine Lunch 14 s Imagine Lunch £ 27 in 360 days max 4. 5 s £ 27 in 360 days 1=yes; 2=no £ 25 now max 4 s Emotional? 0=detach. … 4=highly max 4 s Experiencing? 0=none … 4=highly until 28. 5 s +

summary design • • 2 runs, each 10 trials of each task (Imagine, Estimate, Count) 28. 5 s * 30 trials = 855 s (14. 25 min); 855 s * 2 runs = 1710 s (28. 5 min) Instructions + practicing: ca. 60 min Debriefing: – Consideration of future consequences scale (Strathman et al. , 1994) – Vividness of visual imagery questionnaire (Marks, 1973) – Given the money that you will probably have at those time points, how much will £ 25 be worth to you [now; 30; 90; 180; 360]? • functional sequence: – 64 x 64; 3. 5 x 3. 5 mm pixels; 33 axial slices (3. 5 mm thick, oriented to the AC-PC plane) – TR: 2. 5 s; TE: 40 ms; • structural sequence: MPRAGE? • field maps