This thesis is an investigation of how positive and negative emotions affect driving speed, steering, and hazard response times while controlling arousal. Previous driving literatures have shown emotions to influence attention either by preparing drivers for action or impairing performance. Moreover, the environment exposes the driver to many factors that can change their emotional state. Given that previous experiments commonly confounded valence with arousal, further experiments are needed to determine the different effects of valence and arousal have on attention. Contrary to expectations, results revealed no significant effect of emotional valence on speed and steering. Furthermore, an unexpected interaction between valence and hazard position emerged in reducing brake response time. These findings suggest arousal to have a more important role in attention than previously thought in literature. Moreover, valence and arousal may have different roles in influencing different driving attentional mechanisms.