Department of Psychology, Sun Yat-Sen University, Guangzhou, 510006, China.
Psychol Res. 2021 Sep;85(6):2408-2419. doi: 10.1007/s00426-020-01404-2. Epub 2020 Aug 18.
It has been shown that the capacity of visual working memory (VWM) is a strong predictor of individual intelligence, and researchers have developed various training protocols to improve VWM capacity. However, it seems that whether the fidelity of internal representation in VWM can also be improved by training is largely overlooked in the past literature. Here, we introduced a new training approach that involved increasing the perceptual difficulty of training materials to enhance VWM, and both memory capacity and the fidelity of representation were examined to assess the training efficacy. Participants with normal vision and cognitive abilities received 3-week training on VWM using a change detection task, and the results showed that both the capacity and the fidelity of memory representations were improved for training with perceptually difficult stimuli, while only the fidelity was improved for training with perceptually normal stimuli. In addition, we found that the training effects on memory precision may be subject to capacity constraints. We suggest that long-term adaptive training with perceptually difficult stimuli may facilitate encoding efficiency through familiarizing trainees with an increased baseline of cognitive workload during the encoding process. The present study offers clear evidence that training with high perceptual difficulty is more effective and the improvements in VWM are more stable than training with perceptually normal materials, and the simple manipulation on training stimuli indicates that the method can be generalized to a wider range of training situations and populations.
已有研究表明，视觉工作记忆（VWM）的容量是个体智力的一个强有力的预测指标，研究人员已经开发了各种训练方案来提高 VWM 容量。然而，过去的文献在很大程度上忽略了一个问题，即通过训练是否可以提高 VWM 中内部表示的逼真度。在这里，我们引入了一种新的训练方法，即通过增加训练材料的感知难度来提高 VWM，同时检查记忆容量和表示的逼真度，以评估训练效果。视力和认知能力正常的参与者使用变化检测任务接受了为期 3 周的 VWM 训练，结果表明，对于使用感知困难的刺激进行训练，记忆表示的容量和逼真度都得到了提高，而对于使用感知正常的刺激进行训练，只有逼真度得到了提高。此外，我们发现，记忆精度的训练效果可能受到容量限制。我们认为，通过在编码过程中使受训者熟悉认知工作量增加的基线，使用感知困难的刺激进行长期自适应训练可以通过提高编码效率来促进训练效果。本研究提供了明确的证据，表明使用高感知难度的训练比使用感知正常的材料进行训练更有效，VWM 的改善也更稳定，并且对训练刺激的简单操作表明该方法可以推广到更广泛的训练情况和人群。
