Graham K S, Becker J T, Hodges J R
University Neurology Unit, Addenbrooke's Hospital, Cambridge, U.K.
J Int Neuropsychol Soc. 1997 Nov;3(6):534-44.
Current views of long-term memory presume that both the hippocampal complex and the neocortex play interactive, but separate, roles in the storage of memories. While the neocortex is considered the eventual and permanent store for our memories, the encoding of recently experienced events is thought to be initially dependent upon the hippocampus and closely related structures. Neuropsychological studies have demonstrated that damage to the medial temporal lobe results in a retrograde amnesia extending back in time, with better preservation of older memories. The converse pattern has been shown in patients with semantic dementia, who have focal atrophy of the inferolateral temporal neocortex, but relative sparing of the hippocampal complex (Graham & Hodges, 1997). Here we demonstrate that such patients can show relatively preserved new learning on a forced-choice recognition memory test (based on real and chimeric animals), while patients in the early amnestic phase of Alzheimer's disease show severely impaired learning on the same test. This result provides support for the view that new learning is primarily dependent upon the hippocampus and related structures.
当前对于长期记忆的观点认为，海马复合体和新皮层在记忆存储中发挥着相互作用但又各自独立的作用。虽然新皮层被认为是我们记忆的最终永久存储库，但最近经历事件的编码最初被认为依赖于海马体及与之密切相关的结构。神经心理学研究表明，内侧颞叶受损会导致逆行性遗忘，时间回溯越久，较旧记忆的保存情况越好。语义性痴呆患者呈现出相反的模式，他们的颞叶外侧新皮层有局灶性萎缩，但海马复合体相对未受影响（格雷厄姆和霍奇斯，1997年）。在此我们证明，此类患者在强制选择识别记忆测试（基于真实动物和嵌合体动物）中可表现出相对保留的新学习能力，而处于阿尔茨海默病早期遗忘阶段的患者在同一测试中表现出严重受损的学习能力。这一结果支持了新学习主要依赖于海马体及相关结构这一观点。
