Sensation Seeking behaviour:
Sensation Seeking behaviour, is a better description of the type of extreme dare devil or extreme sport type of behaviour, as opposed to risk taking generally. Reckless risk taking is associated with a variety of psychological conditions that do not necessarily display this specific style of risk taking. There are gender differences with sensation seeking behaviour (and risk taking generally), with more men exhibiting this type of behaviour. From an evolutionary perspective, it makes sense that men, classically the hunters and protectors, would be more inclined to take risks.
Type T personality:
People who are high on the sensation seeking scale, are not necessarily anti social, but a personality type, which propels them to push the limits of life. The best description I have of this type of personality is the description of being a Type T personality. Channeled positively, this type of personality has the potential to be a high achiever.
The Type T personality has been described as a personality dimension referring to individual differences in stimulation seeking, excitement seeking, thrill seeking, arousal seeking, and risk taking. (1)
Sensation seekers have notable physiological differences from individual's with average risk taking profiles. Their orienting reflex (OR) works in reverse to other individuals. In brief, OR is a creatures natural response to external stimuli, change in environment. An event that would, usually, cause a stressful response in the autonomic nervous system will trigger an entirely different response in this type of personality. Physiologically this personality type is primed for adventure.
One study found that when subjects with high disinhibition scores were presented with a moderate-intensity tone, their heart-rates slowed down on the first exposure, while the heart rates of low sensation-seekers quickened.
Another of his studies, published in the Journal of Personality (Vol. 58, No. 1, pages 313-345) in 1990, indicates that the differences between high and low sensation-seekers extend to the cortex of the brain, with high sensation-seekers showing an "augmenting" electrochemical reaction, or increasing amplitude of cortical-evoked potentials (EPs) in response to increasing intensities of stimulation. Low sensation-seekers, however, demonstrate a reducing reaction, showing little EP increase in relation to increasing stimulus intensity, and sometimes showing a reduction in EP amplitudes at the highest intensities of stimulation. (2)
Monoamine oxidase (MAO) is needed for the chemical cascade in the release of dopamine.
The brain chemistry is also deficit in MAO, which could explain the need for a self induced high, from thrill seeking, to increase the release of dopamine.
In conclusion these extremists, may be an evolutionary necessity for the species. As mentioned in one of the articles, it is this drive to push the boundaries that has caused the species to explore the earth and, even, outer space.
Gender differences in risk taking: A meta-analysis.
Byrnes, James P,et al doi: 10.1037/0033-2909.125.3.367
Type T personality and the Jungian classification system.
Morehouse RE, et al PMID: 2313544 (1)
Risk taking in Extreme Sports: A phenomenological perspective
Brymer, Eric PDF
Frisky, but more risky
Christopher Munsey, American Psychological Association (2)
Higher Nervous Functions: The Orienting Reflex
E N Sokolov DOI: 10.1146/annurev.ph.25.030163.002553
Natural selective attention: Orienting and emotion
Margaret M. Bradley DOI: 10.1111/j.1469-8986.2008.00702.x
Risk taking: A study in cognition and personality.
Kogan, Nathan; Wallach, Michael A, Oxford, England: Holt, Rinehart & Winston. (1964)
Motivational determinants of risk-taking behavior.
Atkinson, John W doi: 10.1037/h0043445
The life attitudes schedule: a scale to assess adolescent life-enhancing and life-threatening behaviors.
Lewinsohn PM, et al
All supporting evidence for all my claims are within these references