People with aphasia demonstrate impaired production of bound inflectional morphemes, such as noun plurals and possession. They often show greater difficulty in marking possession versus plurality. Using a new tool for eliciting language, the Morphosyntactic Generation test, we assessed people with primary progressive aphasia and those in the acute and chronic phase following left hemisphere stroke. Clinical profiles were associated with different strengths and weaknesses in language production. Performance of the plural was stronger than possessive in group analyses. However, some individuals demonstrated the inverse pattern of performance. These participants provide counter-evidence to the theory that difficulty with marking possessives is purely the result of their greater cognitive-linguistic complexity and support a functional double dissociation between possessives and plurals. The deficits resulted from morphosyntactic impairment. Future work is needed to understand why plural and possessive markers were differently sensitive to neurological disorders of language.

中文翻译：

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复数和所有格“s”之间的双重分离：来自形态句法生成测试的证据

失语症患者表现出约束屈折语素的产生受损，例如名词复数和占有。他们通常在标记控球权和复数时表现出更大的困难。使用一种新的语言诱发工具，即形态句法生成测试，我们评估了原发性进行性失语症患者以及左半球中风后处于急性和慢性期的患者。临床概况与语言生产的不同优势和劣势有关。在群体分析中，复数的表现强于所有格。然而，有些人表现出相反的表现模式。这些参与者为以下理论提供了相反的证据，即标记所有格的困难纯粹是其更大的认知-语言复杂性的结果，并支持所有格和复数之间的功能性双重分离。缺陷是由形态句法障碍引起的。未来的工作需要了解为什么复数和所有格标记对语言的神经障碍不同敏感。