Poster F94, Tuesday, March 28, 8:00 – 10:00 am, Pacific Concourse
Episodic cueing reduces temporal discounting in individuals with damage to the ventromedial prefrontal cortex
Flavia De Luca1,2, Donna Kwan3, Francesca Bianconi2, Violetta Knyagnytska2,3, Carl Craver4, Elisa Ciaramelli1,2, R. Shayna Rosenbaum3,5; 1Università di Bologna, Italia, 2Centro studi e ricerche in Neuroscienze Cognitive, Università di Bologna, Cesena, Italia, 3York University, Toronto, Ontario, Canada, 4Washington University, St. Louis, USA, 5Rotman Research Institute, Baycrest, Toronto, Canada
Temporal discounting (TD) is the tendency to devalue rewards systematically as the time of their delivery is pushed ahead into the future. Patients with lesions to the ventromedial prefrontal cortex (vmPFC patients) have steep TD, suggesting that vmPFC might play a crucial role in the valuation of future rewards. vmPFC patients also have deficits imagining specific personal future events, raising the possibility of a common underlying impairment mediating vmPFC patients' impairment in episodic future thinking and steep TD. Here, we test whether promoting episodic simulation of future events during choice reduces TD in vmPFC patients. Eleven vmPFC patients and forty-one healthy controls underwent a TD task in two conditions: In the 'standard condition', subjects chose hypothetically between smaller, immediate monetary rewards and larger rewards available at different time delays. In the 'episodic-cueing' condition, participants performed the TD task after having simulated a personal event to occur at each of the delays. In both conditions, the TD task involved rewards of different magnitude. The results showed that controls, but not vmPFC patients, modulated TD depending on reward magnitude. Moreover, vmPFC patients showed steeper TD compared to controls for large rewards. vmPFC patients, however, benefited from episodic cueing as did controls, showing reduced TD in the episodic-cueing compared to the standard condition. Thus, although vmPFC patients' future simulations are poor in detail, they prove capable of modulating the value assigned to future rewards. Cues of the personal future may help activate (personal) semantic structures necessary and sufficient to drive future-oriented decision-making.
Topic Area: LONG-TERM MEMORY: Episodic