KKK9

Saccade countermanding with asymmetric reward David C. Godlove and Jeffrey D. Schall

Department of Psychology, Center for Integrative and Cognitive Neuroscience, Vanderbilt Vision Research Center, Vanderbilt Brain Institute, Vanderbilt University

The saccade countermanding task has been used to elucidate neural mechanisms of saccade control, error detection, and reward processing (reviewed by Schall and Boucher, 2007).

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Asymmetrically rewarded tasks have provided insights into neural and behavioral reward processing effects (Platt and Glimcher, 1999; Sugrue et al., 2004; reviewed by Hikosaka et al., 2006).

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Mean of inhibition functions p < 0.05

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Mean saccade latencies

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We used an asymmetrically rewarded saccade countermanding task to test the effects of reward on motor inhibition.

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Motor inhibition has been studied extensively using the “stop signal” or “countermanding” task (reviewed by Verbruggen and Logan, 2008).

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Vanderbilt University

Race model analysis and SSRT

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Introduction

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Vision Research Center

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Conclusions and future directions Preliminary data suggest that monkeys will speed responses toward rewarded targets and slow responses toward unrewarded targets in the countermanding task. However accuracy also suffers toward rewarded targets and SSRT remains unchanged.

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We will use this task to investigate reward processing and behavioral inhibition at neural levels. We also plan to investigate how reward probability affects error processing in the countermanding task. The large reaction time and accuracy differences seen in this task will provide modeling data suitable for answering several important questions related to the neural instantiation of speed/accuracy trade-offs.

Acknowledgements Supported by National Institutes of Health Grants R01-MH055806 and P30-EY008126, the McKnight Endowment Fund for Neuroscience, and Robin and Richard Patton through the E. Bronson Ingram Chair in Neuroscience.

References Hikosaka O, Nakamura K, Nakahara H (2006) Basal ganglia orient eyes to reward. Journal of Neurophysiology 95:567-584. Platt ML, Glimcher PW (1999) Neural correlates of decision variables in parietal cortex. Nature 400:233-238. Schall JD, Boucher L (2007) Executive control of gaze by the frontal lobes. Cogn Affect Behav Neurosci 7:396-412. Sugrue LP, Corrado GS, Newsome WT (2004) Matching behavior and the representation of value in the parietal cortex. Science 304:1782-1787. Verbruggen F, Logan GD (2008) Response inhibition in the stop-signal paradigm. Trends in Cognitive Sciences 12:418-424.