Bizarreness effect

Biological Parallel

Anomaly detection systems prioritize the unexpected—a suddenly silent forest signals predator presence more than familiar sounds. Bizarre or unusual events trigger heightened encoding because statistical outliers often carry survival-critical information. Jumping spiders distinguish familiar from unfamiliar individuals through dishabituation: familiar patterns match memory templates and get ignored, novel patterns trigger investigation. Bumblebees habituate to repeated looming stimuli but dishabituate instantly when stimulus patterns change, reallocating defensive responses to novelty. Prey animals like gazelles encode anomalous movement patterns (irregular gaits, unexpected directions) with heightened attention—these violations of herd behavior often precede predator attacks. This is pattern-break amplification: the memory system allocates extra resources to experiences that violate predictions, as these require model updates.