Addicted to the Rush: The Anatomy of Sensation Seeking

Introduction

For most individuals, the idea of extreme sports, such as skydiving, free climbing, or paragliding, leave us shocked, fascinated, and with one simple question: Why do these dangerous activities excite people? Central to understanding this phenomenon is adrenaline, a key hormone in the nervous system. Adrenaline, or epinephrine, plays a critical role in the body’s “fight-or flight” response, triggering physiological changes such as increased heart rate and blood pressure [1,2]. Adrenaline,synthesized and released by the adrenal medulla, acts as a hormone in the nervous system [1,3]. This not only prepares an individual for immediate threats but also influences behaviors associated with thrill-seeking activities. 

Research on this hormone and the brain’s reward processes, has revealed its major effects on extreme sports participants and introduced the concept of “sensation seeking” [4]. Sensation seeking refers to the desire to achieve an optimal level of arousal by participating in intense and exhilarating activities [6]. American psychologist Dr. Marvin Zuckerman developed  the Sensation Seeking Scale (SSS-V) to quantify this trait, assigning scores based on their desire for stimulation and openness to new experiences [7]. By using the SSS-V, researchers can determine the role of adrenaline in extreme sports participants, shedding light on adrenaline addiction and its impacts on the brain. By examining both the biological factors of adrenaline and personality factors through sensation seeking, researchers can assess the neurological basis behind the motivations of extreme sports participants, potential risks, and future studies [5]. 

The Role of Adrenaline 

The autonomic nervous system consists of two divisions: the parasympathetic nervous system and the sympathetic nervous system [8]. While the parasympathetic nervous system regulates the body’s ability to relax and digest,  the sympathetic nervous system drives the “fight-or-flight” response through adrenaline [8]. The amygdala, a crucial area of the brain that processes fear and threat detection, regulates the release of adrenaline [9]. For example, when the brain senses a threat or danger in extreme sports, the amygdala processes the threat and sends a signal to the hypothalamus to initiate adrenaline release. 

The hypothalamus, which regulates hunger, sleep-wake cycles, and heart rate, is responsible for the secretion of adrenaline from the adrenal gland [10, 11]. The adrenal medulla, located within the adrenal gland atop the kidneys, releases hormones to control the body’s metabolism, immune system, blood pressure, and stress response [12,13]. Adrenaline is secreted by chromaffin cells within the adrenal medulla, causing many physical symptoms in the body, such as increased heart rate, breathing rate, pupil dilation, sweating, and pain reduction  [14,15]. Adrenaline also enhances muscle strength, endurance, and by stimulating motor systems and increasing calcium release to aid in muscle contraction [16]. 

These physiological effects are evolutionarily advantageous, supporting one’s body during a stressful or dangerous situation and preparing the body to escape from the situation. For extreme sport participants, the brain perceives a threat and releases adrenaline, thus causing the feeling of an adrenaline “rush” [17]. 

Sensation Seeking and Risk of High Sensation Seeking 

The Sensation Seeking Scale (SSS-V) measures an individual’s inclination towards  new and diverse experiences [18]. The SSS-V aims to uncover these traits using four primary categories in its questionnaire [4]. An individual’s desire to engage in risky activities describes the Thrill and Adventure Seeking (TAS) component, while an individual’s desire to participate in behaviors that stimulate the mind describe the Experience Seeking (ES) factor [4]. Another factor, Disinhibition (DIS) refers to sensation seeking through activities like drinking and partying, while Boredom Susceptibility (BS) refers to intolerance for unstimulating activities [4]. The sum of the scores of these four components determines an individual’s sensation seeking level, which ranges from zero to forty with higher scores indicating a higher desire to engage in intense and sensation-seeking experiences [4].

Those who participate in extreme sports, like skydiving, achieve higher scores on the SSS-V than those who do not participate in extreme activities [4]. For instance, skiers scored higher on the total SSS-V and TAS scale [4]. As a result of high sensation seeking scores, these individuals tend to underestimate the severity of risk, potentially leading to greater injury rates [4]. This underestimation may arise from their sense of control, particularly due to their extreme preparation and training [19].

Interestingly, the motivations of extreme sport participants closely resemble those of individuals with substance abuse and addiction, including cravings and withdrawal-like symptoms during abstinence from their sport [4,17]. While extreme sports participants experience compulsive-seeking behavior, extreme sports participants often report using autonomy and control over a situation as motivation [19,20]. In a qualitative study conducted by psychologist Robert Heireine, high-ability rock climbers experienced stronger cravings and negative emotions during abstinence compared to average climbers, further emphasizing the addictive nature of the sport  [17,19]. 

The Process of Reward

The brain’s reward system, known as the mesolimbic system, further explains why extreme sport participants are motivated to push themselves to the limit [21]. Dopamine, the primary messenger in the reward system, is primarily produced in the substantia nigra and ventral tegmental area [22]. Dopaminergic neurons project and release dopamine to the nucleus accumbens, a structure important for functions such as feeding, reward, and stress-related behaviors [23,24]. These structures form a comprehensive circuit that displays how we process rewards [23]. Extreme sports participants often focus on achieving specific outcomes rather than simply improving their performance [19]. Another driving factor for participating in extreme sports is influenced by an individual’s personality traits linked to thrill-seeking behaviors, as measured using the SSS-V [4]. 

Conclusion and Future Studies

The connection between adrenaline and the brain’s reward processes explains why extreme sports participants may find their sport addicting. These athletes often find themselves craving the “rush,” prioritizing specific outcomes rather than improving their skills [19]. However, this desire often results in negative emotions, prompting these athletes to pursue riskier actions to satisfy their craving resulting in withdrawal symptoms during abstinence from their sport [4, 17]. 

Future studies of extreme sports participants may use quantitative rather than qualitative measures to evaluate their levels of craving and withdrawal from their sport [17]. Additionally, future research could include analyzing these athletes’ underestimation of risk in  their respective sports and their underlying motivations for engagement in the sport [19]. Overall, the intersection between the role of adrenaline, sensation seeking, and the process of reward highlights why individuals engage in extreme sports but reveal potential consequences including risk of injury that require further research. 

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