Nonverbal Working Memory for Novel Images in Rhesus Monkeys
Nonverbal Working Memory for Novel Images in Rhesus Monkeys
复制标题
DOI：
10.1016/j.cub.2018.10.025
复制
发表时间：
2018-12-17
期刊：
影响因子：
9.2
通讯作者：
Hampton, Robert R.
中科院分区：
文献类型：
--
作者：
Brady, Ryan J.;Hampton, Robert R.
语言表征极大地促进了人类的工作记忆，例如，通过口头复述和对新刺激的口头重新编码。非人类语言的缺失引发了关于非人类工作记忆在多大程度上包括类似机制的问题。有强有力的证据表明，当猴子用高度熟悉的刺激进行测试时，工作记忆中会出现类似排练的主动维持，但当用新的刺激进行测试时则不然，这表明工作记忆依赖于先前编码的表征的存在。这种熟悉和新奇的图像在工作记忆中的差异可能存在，因为缺乏语言，猴子不能以允许工作记忆中的主动维护的方式重新编码新奇的刺激。或者，在早期的研究中，新图像的工作记忆可能已经存在，但行为沉默。在对新图像的测试中，与从未见过的干扰物相比，对要记住的刺激物的高度熟悉可能是识别性能的一个强有力的决定因素，以至于工作记忆的证据被掩盖。在当前的研究中，我们开发了一种技术，用于衰减相对熟悉度作为记忆信号在新刺激的再认测试中的效用。在新的图像测试中，我们观察到并发认知负荷和延迟间隔，表明积极维持工作记忆的记忆障碍。猴子工作记忆的这种灵活性表明，猴子可能会重新编码不熟悉的刺激，以促进工作记忆，并建立了人类语言工作记忆和非语言非人类灵长类动物工作记忆之间的新的相似之处。
Human working memory is greatly facilitated by linguistic representations-for example, by verbal rehearsal and by verbal recoding of novel stimuli. The absence of language in nonhumans raises questions about the extent to which nonhuman working memory includes similar mechanisms. There is strong evidence for rehearsal-like active maintenance in working memory when monkeys are tested with highly familiar stimuli, but not when tested with novel stimuli, suggesting that working memory depends on the existence of previously encoded representations. This difference in working memory for familiar and novel images may exist because, lacking language, monkeys cannot recode novel stimuli in a way that permits active maintenance in working memory. Alternatively, working memory for novel images may have been present, but behaviorally silent, in earlier studies. In tests with novel images, the high familiarity of to-be-remembered stimuli compared to never-before-seen distractors may be such a strong determinant of recognition performance that evidence of working memory is obscured. In the current study, we developed a technique for attenuating the utility of relative familiarity as a mnemonic signal in recognition tests with novel stimuli. In tests with novel images, we observed impairments of memory by concurrent cognitive load and delay interval that indicate actively maintained working memory. This flexibility in monkey working memory suggests that monkeys may recode unfamiliar stimuli to facilitate working memory and establishes new parallels between verbal human working memory and nonverbal nonhuman primate working memory.