## 2 Related Work  
Research has extensively documented the effects of alcohol on driving behavior and visual performance, with studies broadly categorized into those examining driving behaviors and those analyzing visual features through camera-based detection. The impact of alcohol on driving behavior generally intensifies with an increasing blood alcohol concentration (BAC), as shown in numerous studies [7,8]. Alcohol consumption lowers inhibitions, which is often associated with riskier driving behavior [21]. [PERSON] et al. explored this behavioral influence by conducting a study on 14 participants (7 men, 7 women, ages 21-30), where each participant completed two drives under placebo conditions and two under a BAC of 0.065% on separate days. Their analysis revealed that intoxated participants showed significantly higher lane position deviation and more abrupt steering maneuvers. Intoxicated drivers also tended to drive faster, accelerate more aggressively, and display delayed reaction times, particularly in responding to red lights [21]. Similar results were found by [PERSON] et al., who conducted a study on 25 male  
Figure 1: Blue: relative crash risk in relation to blood alcohol concentration (BAC) [7,8]; red: the legal limit in most EU countries. drivers (ages 20-25) with at least three years of driving experience. Participants completed drives under BAC levels of 0.00%, 0.03%, 0.06%, and 0.09% on different days, showing that higher BAC levels were associated with faster speeds through curves and less stable speed control. A higher BAC also worsened lateral movement stability, with deviations in average speed, lane position, and their respective standard deviations [22]. In another study, [PERSON] et al. investigated the impact of varying alcohol dosages on steering behavior during curves. In their study (25 men, ages 20-35), the test subjects drove a test track in a simulator under four different breath alcohol concentrations (BrACs). The steering angle, steering speed (SS), steering reversal rate (SRR), and peak-to-peak (PP) value of the steering angle were examined. The steering speed on radius curves was significantly faster for drivers under the influence of alcohol compared with those given a placebo. SS, SRR, and PP tended to increase as the BrAC increased [23]. [PERSON] et al. demonstrated an additional effect, showing that increased alcohol intake appeared to reduce simulator sickness due to the opposing effects of alcohol (inducing risky driving) and simulator-induced caution. In three test drives under BAC levels of 0.00%, 0.05%, and 0.09%, the subjects under the influence of alcohol tended to drive faster and more aggressively, reducing simulator sickness symptoms [24; 25]. [PERSON] et al. applied a classification and regression tree model to classify driving behaviors under various BAC levels. In this study (22 men, ages 20-35, including 12 professional drivers), subjects completed five drives: one sober, three under BAC levels of 0.02%, 0.05%, and 0.08%, and one fatigued. The model utilized variables such as the variance in average speed (SPAVG), standard deviation of speed (SPSD), lane position average (LPAVG), and standard deviation of lane position (LPSD). The results demonstrated that the model was highly accurate in distinguishing \"alert\" from \"abnormal\" driving (90.9%) and distinguishing between drunk and tired states (94.4%) but less effective in classifying specific BAC levels [26]. In another study, [PERSON] et al. examined the combined effects of THC and alcohol, finding that both substances significantly impaired driving performance, with notable effects on lane deviation, time driven out of lane, reaction time, and headway stability. Together, they significantly amplify the impact and severely degrade driving performance [27]. Other studies focused specifically on reaction time under the influence of alcohol. [PERSON] et al. and [PERSON] et al. [28; 29] found that reaction time worsens with a higher BAC, while driving experience mitigates this effect.