Newly learned novel cues to location are combined with familiar cues but not always with each other

Abstract

Mature perceptual systems can learn new arbitrary sensory signals (novel cues) to properties of the environment, but little is known about the extent to which novel cues are integrated into normal perception. In normal perception, multiple uncertain familiar cues are combined, often near-optimally (reliability-weighted averaging), to increase perceptual precision. We trained observers to use abstract novel cues to estimate horizontal locations of hidden objects on a monitor. In Experiment 1, four groups of observers each learned to use a different novel cue. All groups benefitted from a suboptimal but significant gain in precision using novel and familiar cues together after short-term training (3 x ~1.5 hour sessions), extending previous reports of novel-familiar cue combination. In Experiment 2, we tested whether two novel cues may also be combined with each other. One pair of novel cues could be combined to improve precision but the other could not, at least not after three sessions of repeated training. Overall, our results provide extensive evidence that novel cues can be learned and combined with familiar cues to enhance perception, but mixed evidence for whether perceptual and decision-making systems can extend this ability to the combination of multiple novel cues with only short-term training.