Service de Neuropsychologie et de Neuroréhabilitation, CHUV, Lausanne, Switzerland.
Cortex. 2011 Sep;47(8):931-44. doi: 10.1016/j.cortex.2010.09.005. Epub 2010 Oct 8.
The respective roles of the medial temporal lobe (MTL) structures in memory are controversial. Some authors put forward a modular account according to which episodic memory and recollection-based processes are crucially dependent on the hippocampal formation whereas semantic acquisition and familiarity-based processes rely on the adjacent parahippocampal gyri. Others defend a unitary view. We report the case of VJ, a boy with developmental amnesia of most likely perinatal onset diagnosed at the age of 8. Magnetic resonance imaging (MRI), including quantitative volumetric measurements of the hippocampal formation and of the entorhinal, perirhinal, and temporopolar cortices, showed severe, bilateral atrophy of the hippocampal formation, fornix and mammillary bodies; by contrast, the perirhinal cortex was within normal range and the entorhinal and temporopolar cortex remained within two standard deviations (SDs) from controls' mean. We examined the development of his semantic knowledge from childhood to teenage as well as his recognition and cued recall memory abilities. On tasks tapping semantic memory, VJ increased his raw scores across years at the same rate as children from large standardisation samples, except for one task; he achieved average performance, consistent with his socio-educational background. He performed within normal range on 74% of recognition tests and achieved average to above average scores on 42% of them despite very severe impairment on 82% of episodic recall tasks. Both faces and landscapes-scenes gave rise to above average scores when tested with coloured stimuli. Cued recall, although impaired, was largely superior to free recall. This case supports a modular account of the MTL with episodic, but not semantic memory depending on the hippocampal formation. Furthermore, the overall pattern of findings is consistent with evidence from both brain-damaged and neuroimaging studies indicating that recollection requires intact hippocampal formation and familiarity relies, at least partly, on the adjacent temporal lobe cortex.
内侧颞叶（MTL）结构在记忆中的各自作用存在争议。一些作者提出了一种模块化的解释，根据这种解释，情景记忆和基于回忆的过程主要依赖于海马体，而语义习得和基于熟悉度的过程则依赖于相邻的旁海马回。其他人则支持单一的观点。我们报告了 VJ 的病例，他是一名 8 岁时被诊断为极有可能围产期发病的发育性遗忘症男孩。磁共振成像（MRI），包括海马体和内嗅皮质、旁海马回和颞极皮质的定量容积测量，显示了海马体、穹窿和乳头体的严重双侧萎缩；相比之下，旁海马回在正常范围内，而内嗅皮质和颞极皮质仍在两个标准差（SD）范围内与对照组的平均值。我们检查了他从童年到青少年时期的语义知识发展以及他的识别和线索回忆记忆能力。在测试语义记忆的任务中，VJ 的原始分数逐年增加的速度与来自大标准化样本的儿童相同，除了一项任务；他的表现处于平均水平，与他的社会教育背景一致。他在 74%的识别测试中表现正常，在其中 42%的测试中取得了平均到高于平均的分数，尽管在 82%的情景回忆任务中表现非常严重。当用彩色刺激测试时，人脸和风景场景都能得到高于平均的分数。线索回忆虽然受损，但在很大程度上优于自由回忆。这个病例支持内侧颞叶的模块化解释，即情景记忆，但不包括语义记忆，取决于海马体。此外，总体发现模式与脑损伤和神经影像学研究的证据一致，表明回忆需要完整的海马体，而熟悉度至少部分依赖于相邻的颞叶皮质。
