stress response. Some researchers say that people with high sensa-
tion-seeking personalities tend to have a different sensitivity to the
chemicals involved in the fight or flight response.^24 Mounting evi-
dence suggests that high sensation-seekers react strongly to dopa-
mine (pleasure), and weakly to serotonin (involved with anxiety)
and norepinephrine (energy). Since dopamine is associated with
pleasure and reward, serotonin with inhibition and anxiety, and
norepinephrine with energy arousal, this would mean that high
sensation-seekers may have a completely different response to
stress than someone like me.
If we think through what we have learned so far about how
Nick’s body responds to the biochemicals that drive these choices,
the picture starts to become clear. Dopamine is being released en
masse when he BASE jumps, and he responds powerfully to it, so the
action is more rewarding to him than it would be to most of us.
Serotonin and epinephrine are also being released, but he responds
weakly to these. That means the anxiety the rest of us would experi-
ence is diminished. In addition, it’s entirely probable that Nick has
high levels of MAO and testosterone, which we just learned further
blunt his reactions to certain neurochemicals. The net result? In
a situation where you would think his BIS would be flashing like
a railroad crossing light, “Stop! Please stop!,” the opposite is actually
happening. His BAS is activated, and he’s drawn toward the oppor-
tunity to fall off a bridge. Nick is experiencing his optimal level of
sensation. Nick may actually feel less stress and more pleasure dur-
ing risky and high sensation-seeking activities. This can mean the
difference between a euphoric parachute jump and a terrifying one.
This is almost certainly due to the differences we have
reviewed about how high sensation-seekers respond differently to
stress, and the neurochemicals involved in the fight or flight
response and the neural motivation system. But it could go further
than that. Perhaps the physical sensation of falling is simply more
excruciating to me than it would be to Nick. Maybe my very nervous
system is different than Nick’s, and I actually experience more
physical sensation than Nick does – so much that falling off
a bridge totally overwhelms my system setting off all of the terrified
responses I’ve mentioned throughout this chapter.
Whatever the case, one thing we know for sure is that Nick
doesn’t seem overwhelmed in these incredible circumstances. It
seems pretty clear his optimal level of sensation iswaydifferent
than mine.42 / Buzz!Downloaded from https://www.cambridge.org/core. Access paid by the UCSF Library, on 11 Nov 2019 at 14:20:40, subject to the Cambridge