关键词: 注意刷新, 价值导向, 工作记忆, 刷新频率, 注视时间

Abstract:

Attentional refreshing is the process of promoting and prolonging the activation of information in working memory (WM) by returning it to the focus of attention. This process can prevent the information in WM from fading over time or being disrupted by distractors. Previous studies have demonstrated that attentional refreshing can be guided by retro-cues or influenced by various experiences, such as reward-related or self-related stimuli. Recent studies have also explored the value effect in WM and found that people tend to prioritize more valuable information in WM, indicating that value may play a role in guiding attentional refreshing during retention. In a groundbreaking study by Atkinson et al. (2022), attentional refreshing was shown to partially explain the value effect in WM. However, the study was unable to determine why high-value information was prioritized for refreshing. It has been suggested that the value effect in WM may be due to a biased attentional refreshing procedure where individuals tend to focus more frequently or for longer periods on the more valuable item during retention, as compared to the other items.

To investigate the value-directed attentional refreshing and its underlying mechanism, this study conducted three experiments. The sample size for each experiment was determined using G*power based on prior research, with 24, 23, and 24 participants in Experiments 1, 2, and 3, respectively. All experiments were designed with a within-subject design, with the independent variable being the value of the item (high or low). In Experiments 1 and 2, a value-directed memory paradigm and a dot probe task were used to examine whether high-value information was refreshed with higher priority than low-value information. Participants were asked to memorize 6 letters simultaneously (Experiment 1) or sequentially (Experiment 2) that were each assigned a value (e.g., 1 or 9) and perform a dot probe task during the memory retention stage. The probe stimuli appeared in either high- or low-value positions, and participants had to identify whether the two dots were arranged vertically or horizontally. They were then asked to recall the letters they remembered. Experiment 3 combined a value-directed memory paradigm and a blank screen paradigm and used Eeylink to further explore the mechanism of value-directed attentional refreshing. Participants were asked to memorize 4 regular grey graphs simultaneously, each with a corresponding value, and then a blank screen was presented to record their eye movements. Finally, one of the graphs was probed to test their memory.

The results of Experiment 1 and Experiment 2 indicated that participants exhibited better recall performance for high-value items compared to low-value items, regardless of whether they were presented simultaneously or sequentially. Furthermore, participants had faster reaction times when responding to the dot probe task at the location of high-value items as opposed to low-value items. Experiment 3 also supported the finding that recall performance was better for high-value items than low-value items. Additionally, the study found that participants tended to have more fixations at the location of high-value items than low-value items during the blank screen period. However, there was no significant difference in fixation duration between high-value and low-value items.

The above experiments directly confirmed the value-directed attentional refreshing that high-value information received priority for attentional refreshing in WM retention when compared to low-value information. More importantly, the results indicated that value-directed attentional refreshing might be achieved by increasing the refresh rate of high-value information rather than deploying more time on it. This study contributes to the research on attentional refreshing and provides new insights into how people prioritize information in their daily lives. Moreover, it sheds light on the mechanism of value-directed attentional refreshing and helps develop the time-based resource-sharing model to a certain extent. These findings can aid researchers in developing computational models that simulate people's attentional refreshing process.

Key words: attentional refreshing, value-directed, working memory, refresh rate, fixation duration