Mayes A R, Downes J J, Symons V, Shoqeirat M
Department of Psychology, University of Liverpool, England.
Cortex. 1994 Dec;30(4):543-63. doi: 10.1016/s0010-9452(13)80235-3.
In 1978, Huppert and Piercy introduced a general method for comparing forgetting rates across groups differing in their baseline memory performance. The method has since become a standard for measuring rate of forgetting in amnesia. Using this method, amnesic subjects with presumed damage to midline diencephalic structures have consistently been reported to forget at a normal rate whereas patients with medial temporal lobe damage have sometimes been reported to forget pathologically fast. Conclusions about amnesic forgetting rates using Huppert and Piercy's procedure, however, are unsafe because the matching procedure results in the shortest mean item-presentation-to-test delay being longer in amnesics than control subjects. A further problem with previous work is that frequently the shortest delay at which performance is measured is 10 minutes. An alternative procedure to Huppert and Piercy's is outlined which eliminates the matching confound. An experiment was carried out using this procedure with face stimuli, and with amnesic and control performance matched immediately following study, and then tested at delays of 5, 12, and 30 minutes. Pathologically fast forgetting was observed in a group of 19 amnesics over the first 5 minutes, but between 12 and 30 minutes their controls forgot faster so that the two groups had forgotten the same amount after 30 minutes. A subgroup of nine Korsakoff patients, with probable damage to midline diencephalic structures, showed a similar abnormal forgetting pattern to the remaining 10 amnesics, some of whom had medial temporal lobe damage. A retroactive interference condition was also included for the 12 minute condition at which delay patient and control recognition was mildly and equivalently disrupted. For unknown reasons perhaps related to a storage abnormality, amnesics lose face recognition memory sooner in the first 30 minutes of forgetting than do normal people, who show accelerated forgetting later so as to match patients after 30 minutes delay.
1978年，赫珀特和皮尔西提出了一种通用方法，用于比较基线记忆表现不同的各组之间的遗忘率。从那以后，该方法成为了测量失忆症遗忘率的标准。使用这种方法，据报道，假定中线间脑结构受损的失忆症患者遗忘速度正常，而内侧颞叶受损的患者有时被报道遗忘速度异常快。然而，使用赫珀特和皮尔西的程序得出的关于失忆症遗忘率的结论并不可靠，因为匹配程序导致失忆症患者中从项目呈现到测试的最短平均延迟比对照组受试者更长。先前研究的另一个问题是，经常测量表现的最短延迟是10分钟。概述了一种替代赫珀特和皮尔西方法的程序，该程序消除了匹配混淆。使用该程序对面部刺激进行了一项实验，在学习后立即使失忆症患者和对照组的表现相匹配，然后在5分钟、12分钟和30分钟的延迟后进行测试。在一组19名失忆症患者中，在前5分钟观察到了病理性快速遗忘，但在12分钟至30分钟之间，他们的对照组遗忘得更快，因此两组在30分钟后遗忘的量相同。一组9名可能中线间脑结构受损的柯萨科夫患者表现出与其余10名失忆症患者相似的异常遗忘模式，其中一些患者有内侧颞叶损伤。在12分钟的条件下还包括了一个倒摄干扰条件，在该延迟下患者和对照组的识别受到轻微且同等程度的干扰。出于可能与存储异常相关的未知原因，失忆症患者在遗忘的前30分钟内比正常人更快地失去面部识别记忆，正常人在后期表现出加速遗忘，以便在30分钟延迟后与患者匹配。
