The results provide evidence for competitive encoding of alternat

The results provide evidence for competitive encoding of alternative potential reach plans in PRR and PMd, reflecting the monkeys’ average choice preferences, but being independent of the immediate behavioral choice of the monkey. This is consistent with the idea that the brain utilizes probabilistic representations throughout all stages of the decision process until an action is finally required (Knill and Pouget, 2004). Importantly, our results suggest that in situations of uncertain choice of which transformation rule to apply, the sensorimotor

system can www.selleckchem.com/products/Fasudil-HCl(HA-1077).html construct all potential motor goal alternatives, and then select among these alternatives, once enough evidence for a proper choice is available, rather than preliminarily betting on one of the transformation rules and computing only the single corresponding motor plan. This strategy could denote a valuable and general principle in decision making, allowing a more comprehensive cost-benefit

analysis that includes the consequential costs of the movements associated with each Abiraterone molecular weight choice. In PMG-CI trials (Figure 2), one spatial and one contextual visual cue were presented to the subjects at different times during the trial (ViewSonic VX922 LCD screen; 5 ms off-on-off response time). The peripheral spatial cue was located at one of four possible positions (0°, 90°, 180°, and 270°) with an eccentricity Cell press of 9 cm (14.5° visual angle, VA) relative to the fixation point. The contextual cue consisted of a green (direct-cued) or blue (inferred-cued) frame around the central eye and hand fixation

points. It instructed the subject to reach toward (direct, proreach) or to the position diametrically opposite of the spatial cue (inferred, antireach). A trial was initiated by the monkey by fixating a small red square in the center of the screen (eye fixation tolerance: 2.0-3.0° VA; 224 Hz CCD camera, ET-49B, Thomas Recording, Giessen, Germany) and touching an adjacent white square of the same size (hand fixation tolerance: 4.0° VA, touch screen mounted directly in front of the video screen; IntelliTouch, ELO Systems, Menlo Park, CA). After a random period of 500–1000 ms (fixation period) the spatial cue was shown briefly for 200 ms. During the following 800–2000 ms (memory period) only the fixation squares were visible. The contextual cue was shown for 170 ms at the end of the memory period and the hand fixation square disappeared (GO signal). The monkey had to make a reach toward the instructed goal within a maximum of 700–1000 ms (movement period, 4.9° VA reach tolerance) and hold the goal position for 300–400 ms (feedback period). The monkey received visual feedback about the correct movement goal (filled circle of the same color as the contextual cue at the goal location) at the end of a correct trial. Eye fixation had to be kept throughout the trial.

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