Working memory flips the direction of serial bias through memory-based decision.

Area of Science:

• Cognitive Psychology
• Neuroscience
• Perception Research

Background:

• Serial bias describes how prior stimuli influence perception of new stimuli, either attractively or repulsively.
• Working memory (WM) is consistently implicated in serial bias, but its precise role and the underlying mechanisms (representation vs. decision) are debated.

Purpose of the Study:

• To investigate the role of working memory (WM) in modulating serial bias.
• To determine if serial bias arises from biased stimulus representation or decision-making processes.

Main Methods:

• Utilized an orientation delayed estimation paradigm.
• Incorporated an attention-demanding intervening task to disrupt WM maintenance.
• Analyzed mouse report trajectories and response times to examine response unfolding.

Main Results:

• Serial bias shifted from repulsive to attractive when WM maintenance was interrupted.
• Response trajectories and times indicated that biased representation alone could not explain the observed patterns.

Conclusions:

• Task-irrelevant prior stimuli influence new stimulus decisions, with bias direction modulated by attentional demand during WM maintenance.
• Findings challenge existing theories by highlighting the dynamic role of attention and decision-making in serial bias.