arXiv:2601.15324cs.AI2026-01被引 1

给冻结的Qwen模型加记忆,不改结构不调参,用小模块实现可逆记忆增强。

Prometheus Mind: Retrofitting Memory to Frozen Language Models

  • 用无监督方向发现技术提取语义向量,无需标注数据
  • 在132个案例中准确率94.4%,非正式输入下降至19.4%
  • 模块可一键移除,适合需安全记忆的部署场景

为预训练语言模型添加记忆通常需要修改架构或权重。我们提出Prometheus Mind,通过11个模块化适配器(530MB,7%开销)为冻结的Qwen3-4B模型添加记忆功能,且可完全移除。系统解决四大问题:(1) 提取——提出对比方向发现(CDD),通过最小对无监督识别语义方向;(2) 训练——端到端优化失败,采用分阶段训练各适配器于简单代理任务成功;(3) 注入——学习编码器泛化差,发现lm_head权重行已具备所需映射,无需训练;(4) 隐藏状态坍塌——变压器使'wife'与'brother'相似度超0.98,通过训练投影恢复区分性(0.98→0.09)。在PrometheusExtract-132数据集上,干净输入下检索准确率达94.4%(n=54,95%置信区间[84.9%, 98.1%]),非正式输入(省略、填充词、隐含主语)下降至19.4%(n=36)。主要瓶颈是关系分类(准确率47.3%),导致多数提取错误。

原文摘要 · Abstract (English)

Adding memory to pretrained language models typically requires architectural changes or weight modification. We present Prometheus Mind, which retrofits memory to a frozen Qwen3-4B using 11 modular adapters (530MB, 7% overhead) -- fully reversible by removing the adapters. Building this system required solving four problems: (1) Extraction -- we develop Contrastive Direction Discovery (CDD), which finds semantic directions via minimal pairs without labeled data. (2) Training -- end-to-end optimization collapses; stage-wise training of each adapter on simple proxy tasks succeeds. (3) Injection -- learned encoders fail to generalize; we find that lm_head-weight rows already provide the mapping we need, requiring no training. (4) Hidden state collapse -- transformers make ``wife'' and ``brother'' 0.98+ similar; we train projections to recover distinction (0.98 $\rightarrow$ 0.09). On PrometheusExtract-132 (132 cases), the system achieves 94.4% retrieval on clean inputs (n=54, 95% CI: [84.9%, 98.1%]), degrading to 19.4% on informal inputs with ellipsis, filler words, or implicit subjects (n=36). The primary bottleneck is relation classification (47.3% accuracy), responsible for most extraction errors.

记忆增强适配器冻结模型无监督

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。