Abstract: Sensation seeking is a trait which describes the individual's pursuit of changeable, novel, complex and intense sensory experience. Compared with the low sensation seekers, the high sensation seekers are more likely to engage in high-risk activities to pursue these sensory stimuli. Because high sensation seeking can predict misbehaviors and crimes in teenagers, it is of great theoretical and practical significance to study the cognitive neural mechanism of sensation seeking. Some of the existing studies have partially confirmed Zuckerman's theory of sensation seeking, showing that high sensation seekers are more sensitive to the intensity and changes of stimuli. However, there is a lack of report using materials directly related to risk-taking behaviors to explore the perceptual processing of high sensation seekers, so it is unable to investigate the cognitive neural processing mechanism of high sensation seeking to risk stimuli. According to Zuckerman's theory of sensation seeking and the optimal arousal level, high sensation seekers should have cognitive processing advantages on risk stimuli with neural sensitivity, cause this kind of stimuli can more effectively improve their cortical arousal level to the optimal state. And also, in the previous studies, high sensation seekers showed risk-taking behavior bias, which should be based on the advantage of early automatically perceptual processing. Therefore, the present study focused on the difference between high and low sensation seekers in automatic processing of risk sounds. In this study, a total of 19 high sensation seekers and 18 low sensation seekers were recruited as participants. Passive auditory oddball reversal paradigm was used to examine the early processing differences between individuals with different sensation seeking levels. The sound materials in the experiment were self-made risk sounds (by guns, explosion and emergency brakes) and neutral sounds (by chickens, ducks and geese). Continuous EEG was recorded when participants were receiving oddball and control blocks. In data analysis, we chose N1, P2 and MMN (Mismatch negativity) to systematically investigate the automatic arousal, attentional bias and feature detection ability of high sensation seekers to risk sounds. There are three main results in this study. First, risk sounds evoked significantly larger unconscious N1 in high sensation seekers, which showed that high sensation seekers had a more sensitive primary automatic processing of risk sounds and would have a higher level of cortical arousal. Secondly, the higher P2 of high sensation seekers induced by the risk sounds indicated that high sensation seekers were more sensitive to the risk sounds and showed an automatically attentional bias. Thirdly, risk sounds evoked higher MMN in high sensation seekers, revealing that high sensation seekers were also more sensitive to the changes of the risk sounds and could better detected risky characteristic automatically. In conclusion, the present study found that high sensation seekers had automatic processing advantages for risk sounds on unconscious arousal, selective attention and feature detection. For high sensation seekers, sounds with risky meaning were more exciting and complex, which may meet their needs for risk seeking preference. These findings suggested that the advantage of automatic processing in these three stages might be the cognitive neural mechanism of risk-taking behavior bias.

Key words: high sensation seekers, risk sound, automatic processing advantage, event-related potential (ERP)

摘要： Zuckerman关于感觉寻求特质的唤醒理论认为，高感觉寻求者为提高其大脑唤醒，会不惜以冒险方式来寻求高强度、变化、新异和复杂的刺激经验。既往研究已经证实了高感觉寻求者对高强度的、变化的和新奇的刺激材料的认知加工偏向，但尚缺乏来自复杂的和具有危险意义刺激材料的研究证据。我们运用反转Oddball实验范式，以听觉N1、P2和MMN（Mismatch negativity）为ERPs指标，系统比较了高、低感觉寻求者对危险意义声音的自动唤醒、注意偏向和特征探测这三个方面的认知加工差异。结果发现，高感觉寻求者的N1、P2和MMN波幅均显著大于低感觉寻求者。结果表明，高感觉寻求者对危险意义声音产生了更高的唤醒水平、注意偏向和特征探测自动加工优势，这些优势可能是其偏于冒险行为的认知神经机制。

关键词: 高感觉寻求者, 危险意义声音, 自动加工优势, 事件相关电位