Department of Psychology, Brigham Young University, Provo, UT 84602, USA.
Proc Natl Acad Sci U S A. 2010 Jan 5;107(1):344-8. doi: 10.1073/pnas.0912543107. Epub 2009 Dec 4.
Recognition memory is thought to depend on two distinct processes: recollection and familiarity. There is debate as to whether damage to the hippocampus selectively impairs recollection or whether it impairs both recollection and familiarity. If hippocampal damage selectively impairs recollection but leaves familiarity intact, then patients with circumscribed hippocampal lesions should exhibit the full normal range of low-confidence and high-confidence familiarity-based recognition. High-confidence, familiarity-based decisions are ordinarily accompanied by successful recollection (when memory is intact). However, patients with hippocampal lesions, if recollection is impaired, should frequently experience high-confidence, familiarity-based recognition in the absence of recollection, and this circumstance (termed the "butcher-on-the-bus" phenomenon) should occur more often in patients than in healthy controls. We tested five patients with circumscribed hippocampal damage, asking them to recognize recently studied words as well as to remember the context in which the items were studied. Relative to controls, the patients exhibited no increased tendency to experience the butcher-on-the-bus phenomenon. The simplest explanation of the results is that hippocampal damage impairs familiarity as well as recollection. The same conclusion was suggested when two competing models of recognition memory were used to analyze the data.
再认和熟悉度。关于海马体损伤是否选择性地损害再认，或者是否同时损害再认和熟悉度，存在争议。如果海马体损伤选择性地损害再认但保留熟悉度，那么有局限性海马体损伤的患者应该表现出完整的低置信度和高置信度基于熟悉度的识别范围。高置信度、基于熟悉度的决策通常伴随着成功的再认（在记忆完好的情况下）。然而，如果再认受损，海马体损伤的患者应该经常在没有再认的情况下经历高置信度、基于熟悉度的识别，这种情况（称为“公交车上的屠夫”现象）在患者中比在健康对照组中更常见。我们测试了五名有局限性海马体损伤的患者，要求他们识别最近学习过的单词，并记住这些项目学习的背景。与对照组相比，患者没有表现出更倾向于经历“公交车上的屠夫”现象的趋势。最简单的解释是，海马体损伤既损害了熟悉度，也损害了再认。当使用两种竞争的识别记忆模型来分析数据时，也得出了同样的结论。
