Acute stress modulates early visual perception and decision-making speed in bees without compromising accuracy

Acute stress is known to influence decision-making, but it can also directly affect earlier stages of sensory processing. In humans, stress alters the perception of basic visual features, fine-tuning vision to support faster responses in threatening contexts. Whether stress induces similar changes in early vision in insects and thus affects visually guided decision-making, remains unknown. Here, we examined how acute stress, simulated via vigorous shaking resembling a predatory attack, affects bumblebees sensitivity thresholds for resolution and contrast sensitivity, two basic visual features, as well as their choice behaviour and decision speed in a dual-choice discrimination task. We found that, similar to humans, stress modulated both thresholds. It increased contrast sensitivity thresholds and shifted spatial frequency thresholds toward finer resolution as well as affecting bee final choice behaviour. Not only were stressed bees more likely to commit to a choice, but they did so significantly faster when their early perceptual decisions were accurate. Collectively, our results suggest that stress reshapes bee visual sensitivity and decision-making not only through an increase in reactivity, but with a flexible shift in decision-making driven by perceptual confidence.