Akimoto Yoritaka, Yamaguchi Taiki
Information & Management Systems Engineering, Nagaoka University of Technology, Nagaoka, Japan.
Percept Mot Skills. 2025 Aug;132(4):764-784. doi: 10.1177/00315125251329965. Epub 2025 Mar 24.
Assessing arousal and cognitive load in the context of driving is important because inappropriate arousal and cognitive load increase the risk of accidents. Previous studies using n-back tasks showed that both lateral prefrontal activity and pupil diameter are good indicators of cognitive load. However, the relationship between lateral prefrontal activity and pupil diameter was load-dependent, and a significant positive correlation was observed in the low-load 0-back condition but not in the high-load 3-back condition. In this study, we utilized Near-Infrared Spectroscopy (NIRS) and eye tracking to investigate the load-dependent relationship between lateral prefrontal cortex activity and pupil diameter in the context of driving. Participants drove on a mountain pass using a commercially available driving game, with and without engagement in a secondary conversation task. The NIRS and eye tracker experiments were conducted separately. The results showed that the pupil diameter and Oxy-Hb concentrations in the dorsolateral prefrontal cortex increased significantly in the driving condition that included the conversation task compared to the normal driving condition. Furthermore, we found a significant positive correlation under the high-load conversational driving condition, in which individuals with larger pupil diameters showed greater left dorsolateral prefrontal cortex activity, but not so under low-load normal driving condition. Our findings provide further evidence of a load-dependent relationship between lateral prefrontal cortex activity and pupil diameter and reveal that the relationship was not simply dependent on the degree of cognitive load but also on the nature of the task, possibly due to the differential engagement of executive function and arousal.
在驾驶情境中评估唤醒水平和认知负荷很重要，因为不适当的唤醒水平和认知负荷会增加事故风险。先前使用n-back任务的研究表明，外侧前额叶活动和瞳孔直径都是认知负荷的良好指标。然而，外侧前额叶活动与瞳孔直径之间的关系取决于负荷，在低负荷0-back条件下观察到显著的正相关，而在高负荷3-back条件下则没有。在本研究中，我们利用近红外光谱（NIRS）和眼动追踪技术，研究了驾驶情境中外侧前额叶皮层活动与瞳孔直径之间的负荷依赖性关系。参与者使用一款市售驾驶游戏在山路上驾驶，同时进行和不进行次要对话任务。NIRS和眼动追踪实验分别进行。结果表明，与正常驾驶条件相比，在包含对话任务的驾驶条件下，瞳孔直径和背外侧前额叶皮层的氧合血红蛋白浓度显著增加。此外，我们发现在高负荷对话驾驶条件下存在显著的正相关，即瞳孔直径较大的个体背外侧前额叶皮层活动更强，但在低负荷正常驾驶条件下并非如此。我们的研究结果进一步证明了外侧前额叶皮层活动与瞳孔直径之间的负荷依赖性关系，并揭示这种关系不仅简单地取决于认知负荷的程度，还取决于任务的性质，这可能是由于执行功能和唤醒的不同参与所致。
