The MRC Applied Chaucer Road, Cambridge, UK CB2 2EF.; the University of Cambridge Neurology Unit, Addenbrooke's Hospital, Hills Road, Cambridge, UK CB2 2QQ.
Trends Cogn Sci. 1997 May;1(2):68-72. doi: 10.1016/S1364-6613(97)01022-X.
Semantic memory encompasses knowledge of objects, facts and words. A number of brain regions are probably involved, but the left infero-lateral temporal lobe appears to play a key role. The separability of semantic memory from episodic (or autobiographical) memory is a focus of current debate. Impaired semantic memory is a common feature of Alzheimer's disease but is invariably overshadowed by a profound deficit in episodic memory. In semantic dementia, a rarer disorder associated with focal temporal-lobe atrophy, there is selective loss of semantic memory, characterized by preservation of superordinate knowledge of words, and objects, but loss of finer-grained information. This pattern can be interpreted as a degradation of features from a distributed network of semantic representations. Following Herpes simplex encephalitis, patients sometimes show disproportionate loss of knowledge for natural kinds (e.g. animals) with relative preservation of knowledge about artefacts, this may reflect differential damage to neural systems critical for perceptual as opposed to functional features, perceptual properties being more salient in knowledge about natural kinds.
语义记忆包括对物体、事实和词语的知识。有几个大脑区域可能参与其中，但左侧下外侧颞叶似乎起着关键作用。语义记忆与情景（或自传体）记忆的可分离性是当前争论的焦点。语义记忆受损是阿尔茨海默病的常见特征，但总是被情景记忆的严重缺陷所掩盖。在语义性痴呆中，一种与局灶性颞叶萎缩相关的更罕见的疾病，存在选择性的语义记忆丧失，表现为对单词和物体的上位知识的保留，但丧失了更精细的信息。这种模式可以解释为从语义表示的分布式网络中特征的退化。单纯疱疹性脑炎后，患者有时会出现对自然种类（如动物）的知识不成比例的丧失，而对人工制品的知识相对保留，这可能反映了对神经系统的不同损伤，这些神经系统对感知特征而非功能特征至关重要，感知特征在自然种类的知识中更为突出。
