Coran Monica, Rodriguez-Fornells Antoni, Ramos-Escobar Neus, Laine Matti, Martin Nadine
Temple University, Philadelphia, USA.
Department of Cognition, Development and Educational Psychology, University of Barcelona, 08035 Barcelona, Spain.
Top Lang Disord. 2020 Jan-Mar;40(1):81-109. doi: 10.1097/TLD.0000000000000204.
Of current interest in aphasia research is the relevance of what we can learn from studying word learning ability in aphasia. In a preliminary study, we addressed two issues related to the novel word learning ability of individuals with aphasia. First, as word learning engages large-scale cognitive-linguistic systems (language skills, verbal short-term memory (STM), other memory and executive functions), we probed whether novel word learning practice in three people with aphasia could stimulate these language-related systems. Second, as lesion correlates affecting word learning in aphasia remain unclear, we examined whether the structural integrity of the left arcuate fasciculus (AF) in the same three individuals is related to outcomes of novel word learning practice.
To stimulate word learning systems, our three participants practiced for 4 weeks with an explicit novel word - novel referent word learning task, adopted from the Ancient Farming Equipment learning paradigm (Laine & Salmelin, 2010). The participants' progress on receptive and expressive novel word learning was followed up, and their language and verbal STM abilities as well as single-session novel word learning (Learning to Name Aliens by Gupta, Martin, Abbs, Schwartz & Lipinski, 2006) were tested before and after the practice period. To address the second question, we analyzed the participants' structural MRI scans with respect to the integrity of the left AF and its overlap with the lesion areas.
All participants showed some receptive word learning in the trained task, as well as improvements in verbal STM span at posttest. Two of the three participants also showed improved performance on some of the language outcome measures. One participant with partially spared left AF, especially temporo-parietal connections, exhibited better word learning performance than the other two who had larger damage and disconnection of the AF.
While the present results are preliminary, they open the possibility that novel word learning practice in aphasia may stimulate remaining word learning mechanisms in aphasia, and thereby influence language and verbal STM abilities. These results also suggest that preservation of novel word learning ability in aphasia in part depends on the integrity of the left arcuate track.
目前失语症研究关注的一个问题是，我们能从对失语症患者词汇学习能力的研究中学到什么。在一项初步研究中，我们探讨了与失语症患者新单词学习能力相关的两个问题。第一，由于词汇学习涉及大规模认知语言系统（语言技能、言语短期记忆（STM）、其他记忆和执行功能），我们探究了三名失语症患者的新单词学习练习是否能刺激这些与语言相关的系统。第二，由于影响失语症患者词汇学习的病变相关性仍不明确，我们研究了这三名患者左弓状束（AF）的结构完整性是否与新单词学习练习的结果相关。
为了刺激词汇学习系统，我们的三名参与者采用了源于古代农耕设备学习范式（莱恩和萨尔梅林，2010年）的明确新单词 - 新指代单词学习任务进行了4周的练习。跟踪参与者在接受性和表达性新单词学习方面的进展，并在练习期前后测试他们的语言和言语STM能力以及单次新单词学习（古普塔、马丁、阿布斯、施瓦茨和利平斯基的《学习给外星人命名》，2006年）。为了解决第二个问题，我们分析了参与者关于左AF完整性及其与病变区域重叠情况的结构磁共振成像扫描。
所有参与者在训练任务中都表现出一定的接受性单词学习能力，并且在测试后言语STM广度有所提高。三名参与者中有两名在一些语言结果测量指标上也表现出了更好的成绩。一名左AF部分保留，尤其是颞顶连接完好的参与者，其单词学习表现优于另外两名AF损伤和连接中断更严重的参与者。
虽然目前的结果是初步的，但它们开启了这样一种可能性，即失语症患者的新单词学习练习可能会刺激失语症中剩余的单词学习机制，从而影响语言和言语STM能力。这些结果还表明，失语症患者新单词学习能力的保留部分取决于左弓状束的完整性。
