# Asymmetrical monitoring of subjective asynchronies: a metacognitive generalized STEARC effect

## TL;DR

The study explores how people monitor their errors in judging which of two stimuli appears first, finding a bias in monitoring errors based on spatial direction.

## Contribution

The paper introduces evidence for a metacognitive STEARC effect in monitoring simultaneity perception errors.

## Key findings

- Confidence ratings increased with longer absolute SOA for correct judgments and decreased for incorrect ones.
- Participants could monitor errors only for left-first and bottom-first judgments, indicating a spatial-temporal bias.

## Abstract

Previous studies have demonstrated that human participants can keep track of the magnitude and direction of their trial-to-trial errors in temporal, spatial, and numerical estimates, collectively referred to as “metric error monitoring.” These studies investigated metric error monitoring in an explicit timing/counting context. However, many of our judgments may also depend on temporal mismatches between stimuli where the temporal information is not processed explicitly, which eventually brings about the simultaneity perception. We investigated whether participants can monitor errors in their simultaneity perception. We tested participants in temporal orer judgment (TOJ) task, where they judged which of the two consecutive stimuli (one on each side of the screen) appeared first and reported their confidence rating for each TOJ. The results of all four experiments showed that the confidence judgements for correct judgments increased and for incorrect judgments decreased with longer absolute SOA. A more granular analysis showed that participants could only monitor their errors for left-first and bottom-first judgments, which suggests a metacognitive spatial–temporal association of response codes (STEARC) effect.

The online version contains supplementary material available at 10.1007/s00426-025-02123-2.