, 2008, 2009, 2011; Lovejoy & Krauzlis, 2010). We collected data from two (J and M) adult, male rhesus macaque monkeys (Macaca mulatta) that were 10–15 years of age and weighed 12–15 kg. The monkeys were prepared with standard surgical techniques that have been described Adriamycin purchase in detail

previously, and all experimental protocols for the monkeys were approved by the Institutional Animal Care and Use Committee (of the Salk Institute) and complied with US Public Health Service policy on the humane care and use of laboratory animals. Note that monkey J was referred to as monkey F in Lovejoy & Krauzlis (2010). Monkeys performed the selective attention tasks described in Lovejoy & Krauzlis (2010) and Hafed et al. (2011) (see also Fig. 1A). Briefly, every trial began with the onset of a small white fixation spot (9 × 9 min arc dimensions) similar to that in Hafed et al. (2009) and presented on a CRT display. Monkeys were allowed 500 ms to bring their gaze to within ~1–1.5° around this spot, after which four rings appeared in each visual quadrant in the periphery, alongside the fixation spot. Each ring was 4.4° in radius, with its center being at an eccentricity of 8.2° relative to the central spot. The rings were 0.25°

thick, and their luminance was 25 cd/m2. Background luminance selleck products was 14 cd/m2, and the white fixation spot was of luminance 50 cd/m2. One of the rings was a different color from the remaining three, serving as the cue to attend to the ring’s quadrant, but it had the same luminance as the other three rings. Random dot motion patches (0% coherence) appeared inside each ring after trial onset (radius of the motion patches, 4.25°), and, after some random delay, a brief coherent motion pulse appeared in the cued quadrant as well as in the diametrically

opposite one (called the ‘foil’). The monkeys’ task was to Fossariinae indicate the direction of the brief motion pulse in the cued quadrant, irrespective of the direction of the distracting motion pulse that appeared simultaneously in the diametrically opposite quadrant. In one variant of the task, the monkeys generated a saccade in the direction of the cued motion pulse to indicate their response; in the other variant, they pressed one of four buttons arranged spatially in the four possible directions of motion in the cued pulse. We inactivated the intermediate and deep layers of the SC, as described in detail in Lovejoy & Krauzlis (2010). Briefly, we injected the GABA agonist muscimol (0.3–0.5 μL, 5 μg/μL) into the intermediate and deep layers of the SC with an injection cannula like that described in Chen et al. (2001); supplementary Table 1 of Lovejoy & Krauzlis (2010) provides a complete list of injection volumes for each experiment. We aimed the cannula in the SC retinotopic map such that we could inactivate a population of neurons representing one of the visual quadrants used in the behavioral task of Fig. 1.