Geva Sharon, Truneh Teodros, Seghier Mohamed L, Hope Thomas M H, Leff Alex P, Crinion Jennifer T, Gajardo-Vidal Andrea, Lorca-Puls Diego L, Green David W, Price Cathy J
Wellcome Centre for Human Neuroimaging, University College London, London WC1N 3AR, UK.
University College London Medical School, London WC1E 6BT, UK.
Brain Commun. 2021 Mar 10;3(2):fcab031. doi: 10.1093/braincomms/fcab031. eCollection 2021.
Prior studies have reported inconsistency in the lesion sites associated with verbal short-term memory impairments. Here we asked: How many different lesion sites can account for selective impairments in verbal short-term memory that persist over time, and how consistently do these lesion sites impair verbal short-term memory? We assessed verbal short-term memory impairments using a forward digit span task from the Comprehensive Aphasia Test. First, we identified the incidence of digit span impairments in a sample of 816 stroke survivors (541 males/275 females; age at stroke onset 56 ± 13 years; time post-stroke 4.4 ± 5.2 years). Second, we studied the lesion sites in a subgroup of these patients ( = 39) with left hemisphere damage and selective digit span impairment-defined as impaired digit span with unimpaired spoken picture naming and spoken word comprehension (tests of speech production and speech perception, respectively). Third, we examined how often these lesion sites were observed in patients who either had no digit span impairments or digit span impairments that co-occurred with difficulties in speech perception and/or production tasks. Digit span impairments were observed in 222/816 patients. Almost all (199/222 = 90%) had left hemisphere damage to five small regions in basal ganglia and/or temporo-parietal areas. Even complete damage to one or more of these five regions was not consistently associated with persistent digit span impairment. However, when the same regions were spared, only 5% (23/455) presented with digit span impairments. These data suggest that verbal short-term memory impairments are most consistently associated with damage to left temporo-parietal and basal ganglia structures. Sparing of these regions very rarely results in persistently poor verbal short-term memory. These findings have clinical implications for predicting recovery of verbal short-term memory after stroke.
先前的研究报告了与言语短期记忆障碍相关的病变部位存在不一致性。在此我们提出疑问：有多少不同的病变部位可导致言语短期记忆的选择性损伤持续存在，以及这些病变部位对言语短期记忆的损害一致性如何？我们使用《综合失语症测试》中的顺背数字广度任务评估言语短期记忆障碍。首先，我们在816名中风幸存者样本（541名男性/275名女性；中风发病年龄56±13岁；中风后时间4.4±5.2年）中确定数字广度损伤的发生率。其次，我们研究了这些患者中的一个亚组（n = 39）的病变部位，这些患者有左半球损伤且存在选择性数字广度损伤，即数字广度受损但口语图片命名和口语单词理解未受损（分别为言语产生和言语感知测试）。第三，我们检查了在没有数字广度损伤或数字广度损伤与言语感知和/或产生任务困难同时出现的患者中，这些病变部位出现的频率。在222/816名患者中观察到数字广度损伤。几乎所有患者（199/222 = 90%）左半球基底神经节和/或颞顶叶区域的五个小区域有损伤。即使这五个区域中的一个或多个完全受损，也并非始终与持续性数字广度损伤相关。然而，当相同区域未受损时，只有5%（23/455）出现数字广度损伤。这些数据表明，言语短期记忆障碍最常与左颞顶叶和基底神经节结构损伤相关。这些区域未受损很少会导致言语短期记忆持续较差。这些发现对预测中风后言语短期记忆的恢复具有临床意义。
