Recency effect disappears when information is integrated from independent perceptual sources

TL;DR

This study investigates how the independence of sensory sources affects the integration of information over time, revealing that the recency effect disappears when information is integrated from orthogonal, independent sources.

Contribution

The paper demonstrates that perceptual independence between sources eliminates the recency effect in information integration during decision-making.

Findings

Participants effectively integrated sensory evidence regardless of source or temporal gaps.

Sequence-dependent effects on accuracy disappeared with orthogonal, independent sources.

Confidence was higher for orthogonal sources and unaffected by temporal gaps or sequence.

Abstract

Decision-making often involves integrating discrete pieces of information from distinct sources over time, yet the cognitive mechanisms underlying this integration remain unclear. In this study, we examined how individuals accumulate and integrate discrete sensory evidence. Participants performed a task involving random dot motion stimuli presented in single- and double-pulse trials. These stimuli varied in motion coherence, source consistency of pulses (either the same or orthogonal directions), and temporal gaps between pulses. We found that participants effectively integrated information regardless of source type or temporal gaps. As expected, when both pulses originated from the same source, performance showed a sequence-dependent effect-accuracy was influenced by the order of pulse presentation. However, this effect disappeared when the pulses came from orthogonal sources. Confidence judgments were similarly unaffected by temporal gaps or pulse sequence but were higher when information originated from orthogonal sources. These findings highlight the specific role of perceptual independency on information integration and consequently, on decision-making.