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Perception is fallible. Humans know this, and so do some nonhuman animals like macaque monkeys. When monkeys report more confidence in a perceptual decision, that decision is more likely to be correct. It is not known how neural circuits in the primate brain assess the quality of perceptual decisions. Here, we test two hypotheses. First, that decision confidence is related to the structure of population activity in the sensory cortex. And second, that this relation differs from the one between sensory activity and decision content. We trained macaque monkeys to judge the orientation of ambiguous stimuli and additionally report their confidence in these judgments. We recorded population activity in the primary visual cortex and used decoders to expose the relationship between this activity and the choice-confidence reports. Our analysis validated both hypotheses and suggests that perceptual decisions arise from a neural computation downstream of visual cortex that estimates the most likely interpretation of a sensory response, while decision confidence instead reflects a computation that evaluates whether this sensory response will produce a reliable decision. Our work establishes a direct link between neural population activity in the sensory cortex and the metacognitive ability to introspect about the quality of perceptual decisions.
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This content will become publicly available on April 16, 2026
Will monkeys wager differently as a function of stimulus fluency or when making immediate versus delayed judgements of memory?
Nonhuman animals can engage in forms of metacognitive control and monitoring processes. However, very little testing of the relation between fluency and metacognition has been done in animals, and little research has assessed memory performance in relation to animals making immediate versus delayed judgments of their memory. Here, wagers made by monkeys during test trials served as a form of confidence measure of how well they could complete a memory test. These wagers occurred either after the delay interval between the sample presentation and the test (delayed judgments) or after the sample presentation but before the delay interval and the test (immediate judgments). Overall, no significant difference in performance was found between these two conditions. We also manipulated the fluency of stimuli by either contrasting small (low fluency) or large (high fluency) stimuli or by manipulating size and the degree to which stimuli were of similar perceptual classes (low fluency, harder to distinguish stimuli such as triangular shapes) or were dissimilar in color and shape (high fluency, clip art images). Although low fluency stimuli were remembered at lower levels, the monkeys showed no evidence of adjusting wagering behavior as a function of stimulus type. Thus, the present experiment showed no evidence that monkeys benefitted from delay of judgments of memory and no evidence of stimulus fluency affecting their confidence as measured by their wagering. Rather, most monkeys preferred consistent wagers across all trial types. This may indicate a metacognitive limitation or some other form of behavioral satisficing that led to suboptimal performance.
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- Award ID(s):
- 2043667
- PAR ID:
- 10621631
- Publisher / Repository:
- University of Rijeka
- Date Published:
- Journal Name:
- Psychological Topics
- Volume:
- 34
- Issue:
- 1
- ISSN:
- 1332-0742
- Page Range / eLocation ID:
- 97 to 115
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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