Moss Rehabilitation Research Institute, Philadelphia, PA, United States; University of Pennsylvania, Philadelphia, PA, United States.
Neuropsychologia. 2010 Mar;48(4):909-20. doi: 10.1016/j.neuropsychologia.2009.11.010. Epub 2009 Nov 17.
Semantic short-term memory (STM) deficits have been traditionally defined as an inability to maintain semantic representations over a delay (Martin et al., 1994b). Yet some patients with semantic STM deficits make numerous intrusions of items from previously presented lists, thus presenting an interesting paradox: why should an inability to maintain semantic representations produce an increase in intrusions from earlier lists? In this study, we investigated the relationship between maintenance deficits and susceptibility to interference in a group of 20 aphasic patients characterized with weak semantic or weak phonological STM. Patients and matched control participants performed a modified item-recognition task designed to elicit semantic or phonological interference from list items located one, two, or three trials back (Hamilton & Martin, 2007). Controls demonstrated significant effects of interference in both versions of the task. Interference in patients was predicted by the type and severity of their STM deficit; that is, shorter semantic spans were associated with greater semantic interference and shorter phonological spans were associated with greater phonological interference. We interpret these results through a new perspective, the reactivation hypothesis, and we discuss their importance for accounts emphasizing the contribution of maintenance mechanisms for STM impairments in aphasia as well as susceptibility to interference.
语义短时记忆 (STM) 缺陷传统上被定义为无法在延迟后保持语义表示 (Martin 等人，1994b)。然而，一些语义 STM 缺陷患者会多次侵入先前呈现的列表中的项目，从而呈现出一个有趣的悖论：为什么无法保持语义表示会导致先前列表中的侵入增加？在这项研究中，我们调查了维持缺陷与易受干扰之间的关系，研究对象是一组 20 名有语义或语音 STM 较弱的失语症患者。患者和匹配的对照组参与者执行了一项经过修改的项目识别任务，旨在从位于一个、两个或三个试验后的列表项目中引出语义或语音干扰 (Hamilton 和 Martin，2007)。对照组在任务的两个版本中都表现出明显的干扰效应。患者的干扰受其 STM 缺陷的类型和严重程度的预测；也就是说，较短的语义跨度与更大的语义干扰相关，较短的语音跨度与更大的语音干扰相关。我们通过一个新的视角，即重新激活假说，来解释这些结果，我们讨论了它们对强调维持机制对失语症 STM 损伤的贡献以及对干扰的易感性的解释的重要性。
