Concept · Cognitive Bias: Memory biases and distortions

Boundary extension

Origin: Intraub & Richardson, 1989

Biological Parallel

Predators scanning from cover mentally extend visual scenes beyond edges—spatial prediction systems fill in likely peripheral content because complete environmental models aid planning. Boundary extension is predictive scene completion: memory stores not just what you saw but what probably exists beyond view, because survival often depends on anticipating what's around corners. This is memory as simulation: the brain builds fuller models than sensory input provides.