More than a memory: Confirmatory visual search is not caused by remembering a visual feature

- Search for a target that can be red or not red is biased towards red stimuli.
- We tested whether this is merely due to the presence of a color in memory.
- We find color-based search slopes when color is memorized for search task.
- No color-based search slopes occurred when color just held in memory during search.
- Confirmatory search is unlikely to be due to memory demands alone.

Previous research has demonstrated a preference for positive over negative information in visual search; asking whether a target object is green biases search towards green objects, even when this entails more perceptual processing than searching non-green objects. The present study investigated whether this confirmatory search bias is due to the presence of one particular (e.g., green) color in memory during search. Across two experiments, we show that this is not the critical factor in generating a confirmation bias in search. Search slowed proportionally to the number of stimuli whose color matched the color held in memory only when the color was remembered as part of the search instructions. These results suggest that biased search for information is due to a particular attentional selection strategy, and not to memory-driven attentional biases.