Do you have a strategy? Multimodal signatures of social bargaining in neurodegeneration and frontal lesions

MELLONI, M., BILLEKE, P., BAEZ, S., HESSE, E., DE LA FUENTE, L., FORNO, G., BIRBA, A., GARCÍA CORDERO, I., SIGMAN, M., HUEPE, D., SLACHEVSKY, A., MANES, F., GARCÍA, A. M., SEDEÑO, L. & IBÁÑEZ, A.

La Havana

Congreso; 18th World Congress of the International Organization of Psychophysiology; 2016

International Organization of Psychophysiology

Recursive social decision making requires the use of flexible, context-sensitive long-term strategies for negotiation. To succeed in social bargaining, participants? own perspectives must be dynamically integrated with those of interactors to maximize self-benefits and adapt to the other?s preferences, respectively. This is a pre-requisite to develop a successful long-term self-other integration strategy (SOIS). While such form of strategic interaction is critical to social decision making, little is known about itsneurocognitive correlates. To bridge this gap, we analyzed social bargaining behavior in relation to its structural neural correlates, ongoing brain dynamics (oscillations and related source space), and functional connectivity signatures in healthy subjects and patients offering contrastive lesion models of neurodegeneration and focal stroke: behavioral variant frontotemporal dementia (bvFTD), Alzheimer?s disease (AD), and frontallesions (FL). All groups showed preserved basic bargaining indexes. However, impaired SOIS was found in bvFTD and FL patients, suggesting that social bargaining critically dependsonthe integrity of prefrontalregions. Also, associations between behavioral performance and data from voxel-based morphometry (VBM) and voxel-based lesion-symptom mapping (VLSM) revealed a critical role of prefrontal regions in value integration and strategic decisions for SOIS. Furthermore, as shown by measures of brain dynamics and related sources during the task, SOIS was predicted by anticipatory activity (alpha/beta oscillations with sources in fronto-temporal regions) associated with expectations about others? decisions. This pattern was reduced in all clinical groups, with greater impairments for bvFTD and FL than AD. Finally, fMRI connectivity analysis highlighted a fronto-temporo-parietal network involved in successful SOIS, with selective compromise of long-distance connections in frontal disorders (bvFTD and FL). In sum, this work provides unprecedented evidence of convergent behavioral and neurocognitive signatures of strategic social bargaining in different lesion models. Our findings offer new insights into the critical roles of frontal hubs and associated temporo-parietal networks for strategic social negotiation. [Work partially supported by CONICET, CONICYT/FONDECYT Regular (1130920), COLCIENCIAS (1115-545-31374 and 1115-569-33858), FONCyT-PICT 2012-0412,FONCyT-PICT 2012-1309, FONDAP 15150012, and INECO Foundation].