Acquisition of a novel vocabulary in an amnesic patient

This study explored the ability of a severe amnesic patient (AC) to acquire new vocabulary words. We compared AC's knowledge of words entered into the French lexicon during three different periods: before 1920, between 1965 and 1985, and after 1986 (i.e. after the onset of his amnesia). AC's knowledge was assessed by asking him to give, for each word, its definition (word-definition task), the general domain to which the word belonged ("domain" task), and to generate a sentence containing the word (sentence-generation task). Finally, we administered a recognition task in which AC had to select, for each word, its correct definition amongst four definitions. For all of these tasks, the results showed that AC's performance was similar to that of four control subjects matched for age, education, and profession. In particular, there was no difference with regard to AC's knowledge of words entered into the language after the onset of his amnesia. Therefore, these results indicate that, despite his profound amnesia, AC was able to learn normally new vocabulary words. More generally, they confirm that, at least is some cases, semantic learning can be spared in amnesia.