Phenotypes of high-risk drivers based upon driving risk preference
Authors: G. Brown T. 
Published: November 2015

High-risk drivers (HRDs) prone to repeat episodes of dangerous driving are over-represented in road traffic morbidity, making them important targets for selective prevention. Better understanding of why some drivers engage in risky behavior is a necessary precursor to the design of effective prevention programs. Nevertheless, HRD research has traditionally focused on healthy young drivers and their self-reported personality features and driving behavior or intentions, and not on bona fide HRD populations and direct observation of their risk-taking behaviors of most concern. In total, the complex nature of HRD is not adequately addressed.

A contemporary paradigm for understanding HRD behavior is to identify meaningful subgroups whose members share common characteristics and pathways to risk taking, and thus are likely to show selective treatment responsivity. For this approach, a more integrative, deep-level approach (i.e., beyond reliance on subjective reports) is advantageous. Previous studies by our group into different forms of HRD reveals dysregulation in two neurobiological systems, executive control related to the prefrontal cortex (e.g., 1,2,3), and the cortisol stress response related to the hypothalamic-pituitary-adrenal axis (e.g., 4,5). While promising, the findings are fragmented.

We recently recruited three distinct HRD groups (males, N = 138, aged 19-39 years) based upon documented driving behavior: 1) drivers who engage in multiple forms of risk taking; 2) speeders/reckless drivers; and 3) alcohol impaired drivers, as well as a healthy, aged-matched, non-HRD control group. Assessment included psychosocial adjustment, personality, functional tests and assays of the above neurobiological processes, and simulated driving behavior. Our main hypothesis was that each HRD subgroup possesses a distinct biosocial profile. Preliminary results supported our hypothesis. The mixed profile closely resembles a ‘cold’ antisocial phenotype in which chronic under arousal interferes with avoidance learning - which leads to asocial risk seeking. The speeders/reckless drivers comprise a phenotype involving the most dangerous behavior and externalizing features, including competitiveness, impulsivity, reward driven decision-making, and weak inhibitory control. Interestingly, the impaired drivers showed poor inhibitory control, alcohol misuse, yet safe driving in simulation. This suggests that their risk taking involves and interaction between alcohol misuse and poor inhibitory control. Overall, these findings signal that development of novel and targeted HRD interventions may come from more integrative research approaches.

References:

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