Behavioral and Brain Functions

Background: Driving a car is a complex task requiring coordinated functioning of distributed brain regions. Controlled and safe driving depends on the integrity of the dorsolateral prefrontal cortex (DLPFC), a brain region, which has been shown to mature in late adolescence. Methods: In this study, driving performance of twenty-four male participants was tested in a highend driving simulator before and after the application of transcranial direct current stimulation (tDCS) for 15 minutes over the left or right DLPFC. Results: We show that external modulation of both, the left and the right, DLPFC directly influences driving behavior. Excitation of the DLPFC (by applying anodal tDCS) leads to a more careful driving style in virtual scenarios without the participants noticing changes in their behavior. Conclusion: This study is one of the first to prove that external stimulation of a specific brain area can influence a multi-part behavior in a very complex and everyday-life situation, therefore breaking new ground for therapy at a neural level. Background Standardized so-called "gambling tasks" in which participants can win or loose money by drawing cards from different decks have become an established tool for the investigation of "risk behavior" in psychological and neurophysiological research [Iowa Gambling Task:. [1], Cambridge Gambling Task: [2,3]]. Typically, riskier behavior in these tasks leads to higher gains but also to higher losses. The standardization of such gambling tasks is crucial when considering their clinical application; e.g. in the diagnosis of patients having problems with impulsiveness or planning and decision-making. At a neural level, risk-taking behavior, decision-making and impulsiveness share similar neural networks in the dorsolateral prefrontal cortex (DLPFC) [1]. Patients with lesions in the DLPFC (especially in the right hemisphere) show riskier behavior than a healthy control group [4]. By contrast, lesions in the ventro-medial prefrontal cortex lead to "myopia" for the future, that is, insensitivity for future consequences of present behavior [1]. Interestingly, recent studies have shown that external stimulation of the DLPFC with Transcranial Magnetic Stimulation (TMS) [5] and with Transcranial Direct Current Stimulation (tDCS) [6] can influence risk-taking behavior. The DLPFC is a brain region that matures through to late adolescence [7], and even during the second decade of life [8]. The late myelination of the DLPFC may serve as one possible explanation why adolescent behavior is often characterized by motivational difficulties, addiction and impulsivity [9]. The fact that driving accidents are the Published: 6 August 2008 Behavioral and Brain Functions 2008, 4:34 doi:10.1186/1744-9081-4-34 Received: 20 March 2008 Accepted: 6 August 2008 This article is available from: http://www.behavioralandbrainfunctions. com/content/4/1/34 © 2008 Beeli et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.