The Hazard Perception for the Surrounding Shape of Warning Signs: Evidence From an Event-Related Potentials Study

Recognition Mechanism of Dangerous Goods Marks: Evidence from an Event-Related Potential Study

Dangerous goods marks are the most effective means of alerting individuals to the potential dangers associated with the transport of dangerous goods. In order to gain a better understanding of how dangerous goods marks convey risk information, the cognitive processing of dangerous goods marks was examined by measuring event-related potentials (ERPs). We recruited 23 participants, and their ERP data were recorded. We discovered that the dangerous goods marks elicited a larger P200 amplitude and a smaller N300 amplitude, indicating that, compared to other marks, the dangerous goods marks exhibited stronger warning information and drew more attention from the subjects. Simultaneously, dangerous goods marks elicited insufficient emotional arousal in individuals. Therefore, these findings suggest that the designs of dangerous goods marks need to be improved, such as improving the graphic consistency. Changes in ERP patterns can be used to measure the risk perception level of dangerous goods marks, which can be used as an accurate indicator of the effectiveness of warning sign design. In addition, this study provides a theoretical foundation for the cognitive understanding mechanism of dangerous goods marks.

Electrophysiological evidence for the effectiveness of images versus text in warnings

Warning sign plays an important role in risk avoidance. Many studies have found that images are better warnings than text, while others have revealed flaws of image-only warning signs. To better understand the factors underlying the effectiveness of different types of warning signs (image only, text only, or image and text), this study adopted event-related potential technology to explore the differences at the neurocognitive level using the oddball paradigm and the Go/No-go paradigm. Together, the behavioral and electroencephalogram results showed that text-only warnings had the lowest effectiveness, but there was little difference between the image-only and image-and-text warnings. The differences in the effects of the three warning signs were mainly in the areas of attention and cognitive control, implying differences in the underlying cognitive processes. Therefore, in the design of warning signs, the effects of different design attributes on cognitive processing should be taken into account based on actual needs in order to improve the effectiveness of the signs.

Effects of surrounding frames and inner targeted line segments on event-related potentials in geometric-optical illusions

OBJECTIVE

The Sander illusion and the horizontal-vertical (H-V) illusion are both size and orientation geometric-optical illusions. The Sander geometric figures can be simply regarded as being made up of surrounding frames and inner targeted line segments. Similarly, H-V illusory geometric figures are made up of the targeted line segments. The role of surrounding frames and inner targeted line segments in the perception and cognition of geometric-optical illusions is not well understood.

METHODS

The time course of event-related potentials (ERP) and the ERP-based standardized low-resolution electromagnetic tomography (sLORETA) source localization were investigated in the Sander illusion and the H-V illusion, which had the same length as the targeted line segments, respectively. The P1, N1, P2, N2 and P3 components of the ERP were focused and measured.

RESULTS

The ERP results demonstrated that the existence of surrounding frames in the Sander illusions-induced significant alterations in the P1, N1, P2, N2 and P3 components, compared with the H-V illusion without surrounding frames. In the Sander illusion, different tilted line segments and surrounding frames resulted in significant differences in the P2, N2 and P3 components. The sLORETA results also demonstrated brain activities of source localization as a function of the surrounding frames and the tilted inner line segments.

CONCLUSIONS

These findings implicate that the perceptual and cognitive processes of the geometric-optical illusions are correlated to the surrounding frames/background, as well as the orientation/direction of inner targeted line segments in geometric figures.

Hyperprolactinemia Associated with Attentional Processing and Interference Control Impairments in Patients with Prolactinomas

The cognitive impairment of pituitary adenomas (PAs) has received increasing attention. Hyperprolactinemia and tumor mass effect are the potential causes. The aim of this study was to identify possible cognitive impairment and to further explore the correlation between these indices and prolactin (PRL) levels, based on the control of tumor size. Twenty-seven patients with prolactinomas (patient group) and twenty-six matched health control group (HC group) were enrolled in this study. All participants performed the flanker task while we continuously recorded electroencephalography data. On the behavioral performance level, patients showed a significantly slower reaction time (RT) in both flanker types. Concerning the event-related potentials level, patients elicited reduced P2 and enhanced N2 amplitudes compared with the HC group, suggesting an impairment of attentional processing (P2) and conflict monitoring (N2). Moreover, the patient group also induced lower P3 amplitudes relative to the HC group in both types, indicating that there were deficits in attentional resource allocation ability. We also found a significant correlation between the P3 amplitudes and incongruent condition RTs, as well as the subsequent PRL levels in the patient group. In conclusion, this is an innovative study that reveals the impaired cognition abilities in prolactinomas, and also proposes the possible cognitive toxicity of oversecreted PRL levels, which provides evidence for further research on the cognitive decline in PAs.

The effect of the degree and location of danger in traffic hazard perception: an ERP study

OBJECTIVES

The aim of this study is to explore the influence of the degree and location of the danger of traffic hazards on the neural reaction process.

METHODS

26 automobile drivers were asked to look at the pictures and press buttons on the pictures unrelated to traffic. Electroencephalography responses to traffic-related images were recorded and analyzed.

RESULTS

It was found that danger in the central visual region induced a larger amplitude of the N100 component than in the peripheral visual region and the trend of different hazard levels was consistent. The danger in the central visual area also induced a larger amplitude of the P200 component than in the peripheral vision area. In addition, when the danger appeared in the central visual area (0°), the P200 amplitude induced by the low-hazard situation was smaller than that of the high-hazard situation. When the danger appeared in the peripheral visual area (7°), the P200 amplitude induced by the low-hazard situation was larger than that of the high-hazard situation. Finally, the presence of danger evoked a larger amplitude of the P300 component in the peripheral visual area than in the central visual area and the P300 amplitude was larger in the low-hazard situation than in the high-hazard situation.

CONCLUSIONS

The results suggest that hazards are more easily processed in the central visual area during the early stage of automatic perception. In the later hazard evaluation stage, the hazard in the central visual area and the high-hazard situation were more easily processed.

The Effect of Safety Signs on the Monitoring of Conflict and Erroneous Response

The safety sign is important in our daily life and workplace to prevent potential safety issues. However, it remains undetermined whether the safety signs would influence the cognitive control ability of the people, which serves to guide the behaviors in a goal-directed manner. Therefore, this study aimed to examine the effect of safety signs on cognitive control by uncovering the behavioral performance and neural manifestations underlying the monitoring of conflict and error. The participants performed a flanker task after watching low- and high-hazard safety signs with the electroencephalogram (EEG) data recorded continually. The behavioral results indicated a classic congruency effect with higher accuracy rate and faster response time under a congruent condition compared to an incongruent condition. However, no hazard effect on behavioral performances was observed. The results of event-related potentials (ERPs) demonstrated a more negative N2 elicited by the incongruent trials and an increased (error-related negativity) ERN difference between the error and correct responses in the high-hazard condition compared to those in the low-hazard condition, implying that the monitoring of the conflict and error were both enhanced after watching the high-hazard safety signs. This study contributes to the understanding of the relationship between safety signs and cognitive control, and further expand the measurements that can be applied to assess the effectiveness of safety signs design.

Electrophysiological Correlates of Processing Warning Signs With Different Background Colors: An Event-Related Potentials Investigation

Warning signs, as a type of safety signs, are widely applied in our daily lives to informing people about potential hazards and prompting safe behavior. Although previous studies have paid attention to the color of warning signs, they are mostly based on surveys and behavioral experiments. The neural substrates underlying the perception of warning signs with different background colors remain not clearly characterized. Therefore, this research is intended to address this gap with event-related potentials (ERPs) technique. Warning signs with three different background colors (i.e., white, yellow, and blue) were used in the experiment. The results showed that the perceptual differences between different warning signs were present in the form of differential ERPs components (P1, N1, P2, N2, and P3) though subjects were not required to explicitly attend to the warning signs.

Are We Sensitive to Different Types of Safety Signs? Evidence from ERPs

Purpose

Safety signs are widely used to deliver safety-related information. There are many different types of safety signs. Although previous studies have paid attention to the design and effectiveness of safety signs, little attention has been devoted to investigating how people process the information conveyed by different types of safety signs. Accordingly, the current study is intended to explore the neural mechanisms underlying people’s perception of different types of safety signs.

Methods

Three types of safety signs (prohibition, mandatory and warning signs) were used in the study. We employed questionnaire and event-related potentials (ERPs) experiment with an implicit paradigm to probe how people perceive these three types of safety signs.

Results

Behaviorally, warning signs induced a higher level of perceived hazard than prohibition signs and mandatory signs, and prohibition signs induced a higher level of perceived hazard than mandatory signs. At the brain level, prohibition signs and warning signs led to reduced P2 amplitudes compared to mandatory signs. In addition, warning signs elicited larger N2 and N4 amplitudes than prohibition signs and mandatory signs, and prohibition signs elicited larger N2 and N4 amplitudes than mandatory signs, coinciding with the behavioral results.

Conclusion

Different types of safety signs led to significant differences in individuals’ hazard perception. Based on the neural results, we suggest that the processing of safety signs consists of two stages: the rapid detection of hazard information (indicated by P2) and the conscious integration of hazard information in working memory (indicated by N2 and N4).