In 2015, road crashes resulted in 1.25 million fatalities, devastating individuals, families, and communities worldwide. This coincided with the United Nation's urgent appeal for a "Decade of Action for Road Safety 2011-2020". Human factors, including complex environmental, emotional, cognitive, and behavioural interactions are major contributors to these deaths, yet the nature of most of these interrelationships remains unclear. Depressed mood, both stable and episodic, is a common mental condition and can contribute to risky decision-making and poorer self-control, as does even modest doses of alcohol, all of which negatively affect safe driving capacities. How mood and alcohol combine to affect safe driving abilities is not well understood. The two proposed studies aim to determine the impact of depressed mood and low doses of alcohol on cognitive functioning and driving performance. In the first study, we assess the following factors: stable mood, cognitive functions vital to safe driving, and safe driving capacities of adult drivers.
We then assign the participants to one of three groups exposed to different levels of blood alcohol concentration (BAC): i) 0%; ii) .05%; iii) .08%) and then re-assess them as above. The second study follows a similar procedure in adult drivers, however we now experimentally manipulate two effects: i) episodic mood (depressed or neutral); and ii) BAC (0% or .02%). Comparisons between the resulting four groups will allow us to disentangle complex interactions between mood and alcohol and their influence on safe driving abilities. Integrative examination of mood, neuropsychological functioning, and the effects of alcohol may reveal unexamined, hidden sources of vulnerability, lead to better understanding of risky driving, and ultimately save lives.