, 1989, 1990, 1991): visual responses, strong delay activity, and postsaccadic activity (Figure S2C). In the

context of visual-saccadic tasks, the neurons seemed typical. It could be that metacognitive processing in PFC (and/or FEF) occurs in NVP-BGJ398 clinical trial specific, yet rare, neurons. FEF and PFC activity also may be more dependent on spatial parameters of the task than SEF. FEF neurons can have quite spatially restricted visual receptive and movement fields (Bruce and Goldberg, 1985), but even when we analyzed target locations confined to those fields, we found no metacognition-related effects. Our results complement a recent report that LIP activity correlated with monkeys’ tendency to opt-out of making a decision (Kiani and Shadlen, 2009), suggesting that the activity signals confidence. Both the fundamental task design and the visual stimuli used in the LIP study differed from those used here. Moving-dots stimuli (Kiani and Shadlen, 2009) require evidence accumulation over time, but the decision stage of our task requires detection of a single brief stimulus. A possible advantage INCB024360 concentration of our task is that its brief stimulus presentation demands a more immediate monitoring of the decision to guide the eventual metacognitive judgment. Given the short latency at which the metacognitive signals separated and the long duration of the separation,

SEF neuronal activity seems to transcend general confidence and correspond more to monitoring of the monkeys’ percept. Another possible advantage of our task is that we were able to establish that the metacognition-related signals in SEF represented processes beyond reward anticipation, which was less clear in LIP using the opt-out task (Kiani and Shadlen, 2009) or in OFC using a delayed reward task (Kepecs et al., 2008). Studies of metacognition naturally lead to questions about broader implications. One interpretation is that metacognition is associated with conscious awareness (Nelson, 1996), but we favor a more conservative view that self-monitoring does not presuppose self-awareness

(Reder and Schunn, 1996). As we argued previously (Middlebrooks and Sommer, 2011), metacognition may Chlormezanone be to cognition as corollary discharge is to action; both describe the ability of the brain to internally monitor its operations. Just as it appears that all animals that move have internal circuits for monitoring their movements (Crapse and Sommer, 2008), all animals with even rudimentary cognitive abilities may monitor those abilities. This monitoring ability, however, does not necessarily imply states of self-awareness anywhere near the levels experienced by humans. Two male rhesus monkeys (labeled N, 6.6 kg, and S, 6.0 kg) were surgically prepared for neuronal recordings and eye position measurements. Using aseptic procedures, ceramic screws and an acrylic implant were affixed to the skull.