Why are the batteries in the microwave?: Use of semantic information under uncertainty in a search task

Abstract

A major problem in human cognition is to understand how newly acquired information and long-standing beliefs about the environment combine to make decisions and plan behaviors. Over-dependence on long-standing beliefs may be a significant source of suboptimal decision-making in unusual circumstances. While the contribution of long-standing beliefs about the environment to search in real-world scenes is well-studied, less is known about how new evidence informs search decisions, and it is unclear whether the two sources of information are used together optimally to guide search. The present study expanded on the literature on semantic guidance in visual search by modeling a Bayesian ideal observer’s use of long-standing semantic beliefs and recent experience in an active search task. The ability to adjust expectations to the task environment was simulated using the Bayesian ideal observer, and subjects’ performance was compared to ideal observers that depended on prior knowledge and recent experience to varying degrees. Target locations were either congruent with scene semantics, incongruent with what would be expected from scene semantics, or random. Half of the subjects were able to learn to search for the target in incongruent locations over repeated experimental sessions when it was optimal to do so. These results suggest that searchers can learn to prioritize recent experience over knowledge of scenes in a near-optimal fashion when it is beneficial to do so, as long as the evidence from recent experience was learnable.

Episodic memory processes modulate how schema knowledge is used in spatial memory decisions

“…Preliminary evidence supports the possibility that memory strength and schema information may trade off or compete in the magnitude of their influence on behavior. For example, when participants are searching for objects in scenes, repetition-related improvements in search speed are greater when objects are in random locations compared to schema-consistent locations (Võ & Wolfe, 2013); moreover, across repeated presentations, some participants are able to learn to search for hidden targets in locations that are inconsistent with semantic expectations (Rehrig et al, 2021). Although these studies did not directly assess participants' episodic memory, the results suggest that stronger episodic memory may reduce reliance on schema information.…”