Keishiro Sawa, Carla Zoe Cremer, Tobias Gerstenberg, Sanjay Manohar & Matan Mazor
University of Oxford & Stanford University
Remembering one's past decisions is critical for learning from delayed feedback and maintaining an accurate self-model. Across two gamified experimental paradigms and three experiments (total N = 500), we find that a selective forgetting of unsuccessful guesses operates within minutes, that it evades introspection, and that it affects confidence ratings in memory judgments. Analysis of memory errors reveals that, in reconstructing their past decisions, people integrate what they remember deciding, what they believe they would have decided, and what they would decide now if asked to make the same decision again.
Sawa, K., Cremer, C. Z., Gerstenberg, T., Manohar, S., & Mazor, M. (2026). "I would not have done that": Outcome knowledge distorts memory for decisions made minutes ago. Proceedings of the 48th Annual Conference of the Cognitive Science Society. [PDF]
Note on experiment numbering: Experiments in this repository are numbered differently from the paper. Paper Exp. 1 →
experiments/symmetry, Paper Exp. 2 →experiments/experiment1, Paper Exp. 3 →experiments/experiment2.experiment3andexperiment4are pilots not reported in the CogSci paper.
Participants revealed hidden black squares in a 6×6 grid, then reproduced their exact guess sequence from memory minutes later. A between-subjects manipulation exposed half of participants to symmetric game boards, allowing them to learn a hidden regularity before the memory phase.
- Try it: symmetric version | asymmetric version
- Pre-registration: OSF.IO/3MPB4 —
docs/pre-registrations/prereg_symmetry/ - Data:
data/symmetry/ - Experiment code:
experiments/symmetry/ - Analysis:
analysis/reportSymmetry.Rmd
On each trial, participants chose between three labelled boxes to collect hidden gems, then reproduced their exact choice sequence from memory. Gem locations followed a hidden positional rule, allowing us to test whether learning the rule distorted memory of earlier decisions made before the rule was known.
- Try it: here
- Pre-registration: OSF.IO/K8AT9 —
docs/pre-registrations/prereg1/ - Data:
data/experiment1/ - Experiment code:
experiments/experiment1/ - Analysis:
analysis/exp1_standardised.Rmd
A replication of Experiment 2 in which participants were explicitly told the hidden rule and shown the true gem location on each memory trial, and rated their confidence after each response. This allowed us to test whether outcome-based memory distortions reflect conscious or unconscious processes.
- Try it: here
- Pre-registration: OSF.IO/RDBS7 —
docs/pre-registrations/prereg2/ - Data:
data/experiment2/ - Experiment code:
experiments/experiment2/ - Analysis:
analysis/exp2_standardised.Rmd