MMA: Multimodal Memory Agent
Yihao Lu, Wanru Cheng, Zeyu Zhang, Hao Tang
TL;DR
The paper tackles the reliability of memory-augmented long-horizon agents by addressing retrieval traps and overconfident errors. It introduces MMA, a memory-agent with a Confidence Module that assigns each retrieved memory a reliability score based on source credibility, temporal decay, and cross-memory consensus, enabling reweighting and abstention when evidence is insufficient. It also presents MMA-Bench, a benchmark designed to stress test belief dynamics with controlled reliability priors and cross-modal contradictions, revealing phenomena like the Visual Placebo Effect in RAG-based systems. Across FEVER, LoCoMo, and MMA-Bench, MMA achieves comparable accuracy with substantially improved stability and calibrated abstention, demonstrating the practical value of epistemic prudence in memory-augmented decision making.
Abstract
Long-horizon multimodal agents depend on external memory; however, similarity-based retrieval often surfaces stale, low-credibility, or conflicting items, which can trigger overconfident errors. We propose Multimodal Memory Agent (MMA), which assigns each retrieved memory item a dynamic reliability score by combining source credibility, temporal decay, and conflict-aware network consensus, and uses this signal to reweight evidence and abstain when support is insufficient. We also introduce MMA-Bench, a programmatically generated benchmark for belief dynamics with controlled speaker reliability and structured text-vision contradictions. Using this framework, we uncover the "Visual Placebo Effect", revealing how RAG-based agents inherit latent visual biases from foundation models. On FEVER, MMA matches baseline accuracy while reducing variance by 35.2% and improving selective utility; on LoCoMo, a safety-oriented configuration improves actionable accuracy and reduces wrong answers; on MMA-Bench, MMA reaches 41.18% Type-B accuracy in Vision mode, while the baseline collapses to 0.0% under the same protocol. Code: https://github.com/AIGeeksGroup/MMA.
