Publications

Applied Filters: First Letter Of Title: O Reset
2 Publications

O

Goddard, N., Hood, G., Cohen, J. D., Eddy, W., Genovese, C., Noll, D., & Nystrom, L. E. (1997). Online Analysis of Functional MRI Datasets on Parallel Platforms. The Journal of Supercomputing, 11, 295–318. https://doi.org/10.1023/a:1007964009986
We describe a new capability for analyzing and visualizing brain activity while a subject is performing a cognitive or perceptual task in a magnetic resonance scanner. This online capability integrates geographically distributed hardware (scanner, parallel computer, visualization platform) via commodity networking. We describe how we parallelized the existing analysis software and present results for the three main classes of parallel platforms. Finally we discuss some of the new possibilities this online capability presents for scientific studies and clinical intervention.
Rilling, J. K., Sanfey, A. G., Aronson, J. A., Nystrom, L. E., & Cohen, J. D. (2004). Opposing BOLD responses to reciprocated and unreciprocated altruism in putative reward pathways. NeuroReport, 15, 2539–2243. https://doi.org/10.1097/00001756-200411150-00022
Mesencephalic dopamine neurons are believed to facilitate reward-dependent learning by computing errors in reward predictions. We used fMRI to test whether this system was activated as expected in response to errors in predictions about whether a social partner would reciprocate an act of altruism. Nineteen subjects received fMRI scans as they played a series of single-shot Prisoner s Dilemma games with partners who were outside the scanner. In both ventromedial prefrontal cortex and ventral striatum, reciprocated and unreciprocated cooperation were associated with positive and negative BOLD responses, respectively. Our results are consistent with the hypothesis that mesencephalic dopamine projection sites carry information about errors in reward prediction that allow us to learn who can and cannot be trusted to reciprocate favors.